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31	CHEMISTRY AND MATERIAL SCIENCES	ABS-332
Salt Concentration Effects on Water and Ion Diffusivities in Aqueous Sodium Ion Battery Electrolyte Aditya Wibawa Sakti(a*), Setyanto Tri Wahyudi(b), Faozan Ahmad(b), Noviyan Darmawan(b), Hendradi Hardhienata(b), Husin Alatas(b) a) Global Center for Science and Engineering, Waseda University, Japan * aditya[at]aoni.waseda.jp b) Departemen Fisika, Institut Pertanian Bogor, Indonesia Abstract Sodium-ion battery is a promising alternative to the well-known lithium-ion battery, owing to the large abundance of sodium ion as it can be found directly from the ocean. To further increase the safety aspect of the sodium-ion battery, the aqueous-based electrolyte has been developed. Ion and water diffusivities is one of the most essential properties that have to be considered in developing a good quality electrolytes. To estimate the diffusion coefficient theoretically, the quantum-mechanical(QM)-based molecular dynamics simulations have been performed. During the diffusion process, the overlapping orbitals and orbital polarizations are at play, thus classical molecular dynamics simulation is not sufficient to describe this type of diffusion. In the present work, we employed the density-functional tight-binding (DFTB) method to handle molecular dynamics simulations that contains more than 1000 atoms in the simulated systems. The present work shows that the water and ion diffusions become slower at high salt concentration. Keywords: density-functional tight-binding- sodium ion battery- quantum mechanics- molecular dynamics- diffusion Share Link | Plain Format | Corresponding Author (Aditya Wibawa Sakti)

32	CHEMISTRY AND MATERIAL SCIENCES	ABS-336
Prenylated Flavonoids from the twig bark of Artocarpus camansi (Kluwih) and Their Potential as Anticancer Imam A. Rosyadi (a), Dikhi Firmansyah (a*), Lia D. Juliawaty (a) a) Organic Chemistry Division, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Jl. Ganesha 10 Bandung, Indonesia *dikhfi[at]itb.ac.id Abstract Artocarpus camansi known as kluwih is one of the species belonging to the Artocarpus genus. The main secondary metabolites of this genus are prenylated flavonoids, which have potential as anticancer agent. In this research, the acetone extract of the twig bark of A. camansi was separated and purified using several chromatography techniques to give three prenylflavones, namely cycloartobiloxanthone (1), morusin (2), and artonin E 2^ methylether (3). The structures of these compounds were determined by NMR spectroscopy. Cycloartobiloxanthone is the major secondary metabolite, 75 mg of the compound was obtained from 500 g of powdered twig bark samples. Among all, morusin had the best cytotoxic activity against P388 leukemia cells, IC50 value 3.1 ug/mL. Keywords: Artocarpus camansi, kluwih, prenylflavones, P388 Share Link | Plain Format | Corresponding Author (Imam Ardhi rosyadi)

33	CHEMISTRY AND MATERIAL SCIENCES	ABS-340
The Effect of Ammonium Chloride Concentration in Biopolymer Carrageenan Films as Organic Battery Electrolyte V K Sari (a*), Anisah (a), M A F Turnip (b), M Y P Akbar (b), P Wulandari (b), Paula S Rudati (b) a) Physics of Magnetism and Photonic Research Division, FMIPA, Bandung Institute of Technology Jalan Ganesha 10, Bandung 40132, Indonesia *24722006[at]mahasiswa.itb.ac.id b) Department of Electrical Engineering, Politeknik Negeri Bandung Jl. Gegerkalong Hilir, Bandung Barat 40559, Indonesia Abstract Bio-based polymers have attracted research interest due to interesting characteristics such as flexibility, low-cost material and it is easy to prepare in a large area film. Commonly biopolymers based on polysaccharides are chitosan, cellulose, starch, and carrageenan. In this study, we attempt to optimize and analyse the effect of ammonium chloride (NH4Cl) addition into &#954--carrageenan as electrolyte regarding to the performance of organic battery electrolyte. We used various concentrations of NH4Cl into kappa carrageenan solution to form thin films and investigate its chemical, mechanical and electric properties. The results show the morphology of mixed kappa carrageenan and NH4Cl with concentration of 0.45 g is a smoother than that of a pristine &#954--carrageenan. FTIR spectra shows there are no significant chemical interaction between kappa carrageenan and NH4Cl even though for the symmetric stretching of O-S-O from kappa carrageenan shifted to low frequency after addition of NH4Cl We found that the incorporation of NH4Cl increase the film flexibility with the elongation is about 4 mm and it enhance the film conductivity about 1.02 x 10-6 S/m. Based on our investigation, the kappa carrageenan with NH4Cl can be apply for device application, since it is successful to produce a battery performance by charging process with charging voltage is 4.6 V with the lifetime about 500 seconds. Keywords: ammonium chloride- carrageenan- battery Share Link | Plain Format | Corresponding Author (Visi Komala Sari)

34	CHEMISTRY AND MATERIAL SCIENCES	ABS-342
Physicochemical investigation of blackening process of rock art pigment in Leang Lompoa (Pangkep Regency, South Sulawesi, Indonesia) Moh. Mualliful Ilmi (a*), Grandprix Thomryes Marth Kadja (b,c), Pindi Setiawan (d), Djulia Onggo (b), Ismunandar (b) a) Chemistry Laboratory, Department of Pharmacy, Universitas Nahdlatul Ulama Sunan Giri Bojonegoro, Jl. A Yani no. 10, Bojonegoro 62115, Indonesia *ilmi.kimia[at]gmail.com b) Division of Inorganic and Physical Chemistry, Institut Teknologi Bandung, Jl. Ganesha no. 10, Bandung 40132, Indonesia c) Research Center for Nanosciences and Nanotechnology, Institut Teknologi Bandung, Jl. Ganesha No. 10, Bandung 40132, Indonesia d) Division of Visual Communication and Multimedia, Institut Teknologi Bandung, Jl. Ganesha no. 10, Bandung 40132, Indonesia Abstract The color change process is among the various threats endangering the preservation of the Maros-Pangkep rock art. Among the rock art sites in the Maros-Pangkep Region experiencing the color change of rock art pigments is Leang Lompoa. The color change process is indicated the presence of black deposits covering several hand stencils images. In this work, we aim to investigate the blackening process in rock art in Leang Lompoa by studying the physicochemical properties of the pigment. Here, we employed a combined multi-analytical characterization, including optical microscopy observation, elemental analyzes of X-ray fluorescence (XRF), scanning electron microscopy coupled with energy dispersive electron spectroscopy (SEM-EDS), and Raman spectroscopy. The result indicates that the blackening process of the rock art of Leang Lompoa was due to the formation of black deposit made up charcoal. It was confirmed by by the presence of peaks of D and G Bands at Raman shifts of 1326 cm-1 and 1598 cm-1. Charcoal deposits can originate from the accumulation of soot generated by anthropogenic activities around the site. In addition, the deposit may also have formed due to an accidental fire on a haystack on the site, where the Leang Lompoa site is now used as a hay storage area by the local population. Keywords: Rock art, burning, black deposit, Leang Lompoa, Pangkep, Indonesia Share Link | Plain Format | Corresponding Author (Moh. Mualliful Ilmi)

35	CHEMISTRY AND MATERIAL SCIENCES	ABS-88
Crystal growing of [Fe(3-bpp)2]Cl2.6.5H2O complex Fitriani (a,b), Djulia Onggo (a), Irma Mulyani (a*), M. Abdulkadir Martoprawiro (a) a) Inorganic and Physical Chemistry Research Group Faculty of Mathematics and Natural Sciences Institut Teknologi Bandung, Jl. Ganesha 10 Bandung 40132 Indonesia b) Department of Chemistry Education, Universitas Muhammadiyah Pontianak Jl. Ahmad Yani 111 Pontianak 78123 Indonesia *imulyani[at]itb.ac.id Abstract The bis 2,6-bis(pyrazo1-3-y1)pyridine (3-bpp) of iron(II) complexes ([Fe(3bpp)2]2+) have been intensively investigated since exhibiting Spin Crossover (SCO) properties that depend on the ligand field strength and also the counter anion type. Generally, the [Fe(3-bpp)2]A2 complexes with various counter anions (A) were prepared by replacing the chloride anion of [Fe(3-bpp)2]Cl2 with other counter anions, using their sodium or potassium salts. The chloride anion is usually easy to be replaced by other counter anions. In the previous report, the [Fe(3-bpp)2]Cl2 6.5H2O complex was surprisingly isolated from the reaction of [Fe(3-bpp)2]I2 with excess silver chloride by agitation method. The iodide was replaced successfully by the chloride anion and the structure was solved perfectly. As a result of our study, the replacement of the chloride anions from the [Fe(3bpp)2]Cl2 complex by the [Ni(CN)42&#61485-] anions was observed in the solid product of [Fe(3bpp)2]Ni(CN)4, which was obtained from the reaction between the [Fe(3-bpp)2]Cl2 dan K2[Ni(CN)4] solutions. However, crystals of [Fe(3-bpp)2]Cl2 were grown perfectly from solution filtrate which was the remaining solution of that reaction. To confirm this finding, we prepared the mixture of aqueous methanolic solutions of FeCl2 and 3-bpp ligand without the addition of K2Ni(CN)4 solution. Single crystals of [Fe(3-bpp)2]Cl2 were obtained in reasonable amounts. Keywords: Iron(II) complexes, 2,6-bis(pyrazol-3-yl)pyridine, chloride anion Share Link | Plain Format | Corresponding Author (Fitriani Fitriani)

36	CHEMISTRY AND MATERIAL SCIENCES	ABS-93
Tunable reversible reaction of paraldehyde with aluminosilicate catalyst Nadia Tuada A, Rindia Maharani P, Didin Mujahidin, Zeily Nurachman Institut Teknologi Bandung Abstract Please Just Try to Submit This Sample Abstract You Can Edit It Again Later Keywords: Aluminosilicate, Paraldehyde, Tunable reaction Share Link | Plain Format | Corresponding Author (Nadia Afnan)

37	CHEMISTRY AND MATERIAL SCIENCES	ABS-355
Molecular Mechanism Elucidation of the Nickel-Catalyzed Catalytic Transfer Hydrogenation of Furfural to Furfuryl Alcohol Nova Pratiwi Indriyani(a), Azi Ibnu Sulistia(a), Yessi Permana(a*), Muhamad Abdulkadir Martoprawiro(a), I Made Arcana(a) a) Department of Chemistry, Faculty of Mathematics and Natural Science, Institut Teknologi Bandung * yessipermana[at]gmail.com Abstract Current methods for hydrogenation of furfural are limited by their use of noble metals, such as Ru, Pd, Pt, Ir, and Au as catalysts at high pressures of hydrogen (up to 100 bar). In this work, the air-stable and inexpensive Ni (II) phosphine complex, NiCl2(PPh3)2, was used as a catalytic transfer hydrogenation (CTH) precursor in furfural (FAL) valorization in the presence of Zn as a reducing agent and ethanol as the hydrogen source, to produce furfuryl alcohol (FOL) under relatively mild conditions (7 h, 433 K). Experimental studies suggest the rule of Ni(0) phosphine complex as an active species in this catalytic reaction. Quantum chemistry calculations were performed at density-functional theory level by employing the MN15L functional to elucidate the reaction mechanism in prior to an efficient catalyst design. The present work proposes two reaction schemes for the CTH of FAL, namely, via the formation of dihydride and monohydride of Ni(II). Based on the calculated free energy barriers, the hydride transfer is the rate determining step of the reaction scheme that involves the dihydride Ni(II) formation (Scheme 1). In contrast, the proton transfer is the rate determining step (RDS) for the reaction scheme via the monohydride Ni(II) route (Scheme 2). While the Scheme 1 cannot explain the effects of variation on the hydrogen source, Scheme 2 predicts a lower activation barrier for the proton transfer process. This work suggests that Scheme 2 is a more plausible mechanism for the CTH of FAL to FOL. Keywords: hydrogenation- furfural- furfuryl alcohol- density-functional theory- MN15L Share Link | Plain Format | Corresponding Author (Nova Pratiwi Indriyani)

38	CHEMISTRY AND MATERIAL SCIENCES	ABS-362
ANALYSIS OF THE LEVELS OF ALKALOID AND TANIN EXTRACT OF AROGO LEAF (Premna serratifolia) Minarni Rama Jura (*), Siti Nuryanti, Anang Wahid M Diah, Sitti Rahmawati, Vivi Diah Sangkota,Metsiana F Y Buriko Department of Mathematics and Natural Sciences Education, Faculty of Teacher Training and Education, Tadulako University, Palu City, Indonesia Abstract Arogo (Premna serratifolia) is one of the plants that has the potential as a traditional medicinal plant to treat various diseases. The purpose of this study was to analyze the levels of alkaloids and tannins in arogo leaf extract. Arogo leaves were extracted by the meseration method using 96% ethanol as solvent and the extract was evaporated using a rotary evaporator at a temperature of 40&#8451-. Identification of alkaloids in the extract using Meyer and Dragendrof reagents and identification of tannins using FeCl3. Analysis of alkaloid and tannin levels was carried out using UV Vis spectrophotometer method at a wavelength of 273 nm for alkaloid content and a wavelength of 765 nm for tannin content. The results showed that positive arogo leaves contain alkaloids and tannins. The results of the analysis of the alkaloid content of arogo leaf extract were 0,962% and the tannin content analysis was 11,933%. Keywords: Alkaloids, Tannins, Arogo Leaves (Premna serratifolia), Uv-Vis Spectrophotometer Share Link | Plain Format | Corresponding Author (Minarni Ramajura)

39	CHEMISTRY AND MATERIAL SCIENCES	ABS-363
UTILIZATION OF BANANA PEEL WASTE FOR CHARCOAL BRIQUETTE PRODUCTION AS AN ALTERNATIVE FUEL Sitti Rahmawati (*), Dewi Satria Ahmar, Purnama Ningsih, Tri Santoso, Magfirah 1Departement of Mathematic^s and Natural Sciences Education, Faculty of Teacher Training and Education, Tadulako University, Jl. Soekarno Hatta Km 9 City of Palu, 94118, Central Sulawesi, Indonesia Abstract There is a lot of banana skin waste in Palu city every day and it is only transported to a landfill. One alternative to reduce banana peel waste is to use this waste as a material for making charcoal briquettes. This study aims to make and measure the characteristic parameters of the resulting banana peel briquette charcoal. The stages of making charcoal briquettes are collecting raw materials, drying raw materials, carbonization, mashing, sieving, mixing adhesive materials, printing, drying and determining the characteristics of briquettes. Variations in the composition of banana peels and tapioca starch adhesives in this study were: 90%:10%, 85%:15%, and 80%:20%. The results of testing the characteristics of briquettes on density obtained values ranging from 0.463 gr/cm3 - 0.5662 g/cm3, compressive strength ranging from 21.9588-32.6662 kg/cm2, moisture content ranging from 3.6451-6.4464%, ash content ranged from 16.736-17.930%, volatile matter content ranged from 58.474-60.873%, bound carbon content ranged from 14.7512-21.1449%, and heating value ranged from 7406.846-9864.683 cal/g and burning rate of 0.14 gr/sec. variations in composition with the best characteristic test results that meet several Indonesian National Standards (SNI), namely at a ratio of 85%:15%. Banana peels can be used as a raw material for making charcoal briquettes and produce heat energy as an energy source Keywords: Banana skin- briquette charcoal- burning rate Share Link | Plain Format | Corresponding Author (sitti rahmawati)

40	CHEMISTRY AND MATERIAL SCIENCES	ABS-367
Catalytic Pyrolysis of the Green Microalgae Botryococcus braunii over Ni/SBA-15 RR Dirgarini Julia Nurlianti Subagyono (a)*, Sri Astika Putri (a) , Maykel Manawan (b) , Mamun Mollah (c) , Rudy Agung Nugroho (d) , Rahmat Gunawan (a) (a) Physical Chemistry Laboratory, Chemistry Department, Mulawarman University, Samarinda, East Kalimantan, Indonesia (b) Indonesia Defense University, Bogor, West Java, Indonesia (c) School of Chemistry, Monash University, Clayton, Victoria 3800, Australia (d) Biology Department, Mulawarman University, Samarinda, East Kalimantan, Indonesia Abstract The pyrolysis of the green microalgae Botryococcus braunii in the absence and the presence of Ni/SBA-15 prepared by the ultrasonic-assisted sol-gel was investigated using pyrolysis-gas chromatography-mass spectroscopy (Py-GC/MS). Pyrolysis experiments were performed at 350, 450, and 550 degree C under helium (He) flow. The addition of 10% Ni/SBA-15 enhanced the production of aromatic compounds, such as furans, furfurals, alkyl aromatics, and nitrogen aromatic compounds. These were the thermal degradation products of carbohydrates and proteins. Thermogravimetric analyses showed that the temperature range for the pyrolysis of Botryococcus braunii was 135-547 degree C, while that of the catalyzed pyrolysis was 135-532 degree C. Keywords: Botryococcus braunii, pyrolysis, Ni/SBA-15 Share Link | Plain Format | Corresponding Author (RR Dirgarini Julia Nurlianti Subagyono)

41	CHEMISTRY AND MATERIAL SCIENCES	ABS-369
Prospects of Nickel Complexes Immobilized on MOF Catalyst for Double Bond Isomerization Catalysis Arif Rahman, Djulia Onggo, Yessi Permana Departemen Kimia, Institut Teknologi Bandung Abstract Improvements in the performance and stability of organonickel catalysts in polymerization, hydrogenation, oxidation catalytic systems, as well as in growing carbon nanotubes and graphene, have driven the outstanding applications and strong practical applications of organonickel-based catalysts. Improvement of ligands in nickel complex compounds is the key to the design of homogeneous nickel catalysts, and understanding the role of the nanoscale environment has played a major role in the development of solid nickel catalysts. The role of ligands in various catalytic systems makes it possible to utilize various reagents with very simple and inexpensive catalyst precursors. Developing stable ligands in organonickel compounds into solid catalysts has challenges related to the stability of the ligands against oxidation and temperature. Immobilization on solids with a large surface area provides an opportunity but has the potential to reduce the performance activity of the catalyst. This paper will review the role of ligands and their development in nickel catalyst isomerization of carbon double bonds and the chances of immobilization in MOFs, which are hollow solids with a framework structure in the form of ligands. This review presents selected examples of literature that draw attention to important fundamental aspects of nickel chemistry and highlight promising directions for developing catalysts in heterogeneous systems. Keywords: Nickel complexes, MOFs, Isomerization, double-bond Share Link | Plain Format | Corresponding Author (Arif Rahman)

42	CHEMISTRY AND MATERIAL SCIENCES	ABS-371
Synthesis and Characterization of TiO2/ZnO Photocatalyst Composite Material Siti Oryza Sativa, Muhammad Ali Zulfikar, Aep Patah, Wibawa Hendra Saputera Institut Teknologi Bandung Abstract The Textile and Textile Product (TPT) industry is the manufacturing sector that recorded the highest growth in the quarter of 2019. As an industry that produces textile products, dyes are used during the dyeing process. Synthetic dyes are more often used in the coloring process because they are cheap and the colors produced are brighter than natural dyes. Processing of dye waste that is not carried out properly causes pollution of the soil and water environment, so it is necessary to carry out further effective and efficient processing. This research proposes photocatalytic processing of dye waste. Photocatalytic reactions require photocatalyst materials. The photocatalytic method has advantages because it is economical, low toxic, does not form sludge, is environmentally friendly, low energy consumption and can be reused. TiO2 material modified with ZnO will be synthesized and characterized for processing dye waste. It is hoped that this research will contribute to the field of material chemistry and the environment. TiO2 has a band gap energy of 3.2 eV so that this material still works in the UV light range. It is known that sunlight has about 5% UV light and 45% visible light, so it is necessary to modify TiO2 so it can work under visible light. Keywords: photocatalysis, photocatalyst material, TiO2/ZnO Share Link | Plain Format | Corresponding Author (Siti Oryza Sativa)

43	CHEMISTRY AND MATERIAL SCIENCES	ABS-129
Structural and Luminescence Properties of Ca\(^{2+}\)-Substituted Self-Activated Photoluminescence Material of Na\(_{2}\)TiSiO\(_{5}\) Dzaky Dian Ruhimat (a), Fainan Failamani (a), Bambang Prijamboedi (a), * (a) Inorganic and Physical Chemistry Research Division, Faculty of Mathematics and Natural Sciences, Bandung Institute of Technology Jl. Ganesha 10, Bandung, 40132, INDONESIA *E-mail : prijamboedi[at]itb.ac.id Abstract White light emitting diode (WLED) is widely used as lighting devices. Self-activated luminescence materials, such as Na\(_{2}\)TiSiO\(_{5}\) (NTSO) becomes a good candidate for the WLED emitting device, because it does not contain any rare-earth elements as luminescence center. However, the low emission intensity of NTSO limits its application as commercial LED. In order to improve its luminescence intensity, one needs to study the photoluminescence mechanism. It was proposed that the different coordination of Ti\(^{4+}\) is responsible for the luminescence properties. Therefore, we study the effects of Ca\(^{2+}\) substitution into Na\(^{+}\) site in NTSO. The Ca\(^{2+}\) ions are expected to change the coordination of Ti\(^{4+}\). The Na\(_{2(1-x)}\)Ca\(_{x}\)TiSiO\(_{5}\) (x = 0.00, 0.50, 1.00) samples were synthesized by means of solid state method, and its structural properties were characterized and analyzed by X-ray diffraction (XRD) method and Rietveld refinement, respectively. The local Ti\(^{4+}\)-O\(^{2-}\) coordination is studied by IR spectroscopy. The absorption and emission properties were studied by UV diffuse reflectance spectroscopy (UV-DRS) and photoluminescence (PL) spectroscopy, respectively. The effects of Ca\(^{2+}\)-substitution into NTSO to the crystal structure, optical absorption and emission would reveal the photoluminescence mechanism in this compound. Keywords: Photoluminescence- rare-earth free- self-activated- Na\(_{2}\)TiSiO\(_{5}\) Share Link | Plain Format | Corresponding Author (Dzaky Dian Ruhimat)

44	CHEMISTRY AND MATERIAL SCIENCES	ABS-130
The Elucidation of Cu-Zn Surface Alloying by Machine Learning Molecular Dynamics Harry H. Halim (a*), Yoshitada Morikawa (b) Graduate School of Engineering, Osaka University Abstract The Cu-Zn surface alloy has been extensively involved in the investigation of the active site of Cu/ZnO/Al2O3, the industrial catalysts for methanol synthesis which remains under controversy.[1-2] To provide better understanding of the dynamic of Cu-Zn surface at the atomic level, the structure and the formation process of Cu-Zn surface alloy on Cu(997) were investigated by machine-learning molecular dynamics. Gaussian Process (GP) regression aided with on-the-fly learning were employed to build force-field used to drive molecular dynamics simulation.[3] The simulation reveals atomistic details of the alloying process, i.e., the incorporation of deposited Zn adatoms to the Cu substrate. The surface alloying is found to start at upper and lower terraces near the step edge, which emphasize the role of steps and kinks in the alloying. The incorporation of Zn at the middle terrace was found at the later stage of the simulation. The rationalization of alloying behavior was performed based on statistics and barriers of various elementary events that occur during the simulation. It was observed that the alloying scheme at upper terrace is dominated by the confinement of Zn step adatom by other adatoms, highlighting the importance of step fluctuations in the alloying process. On the other hand, the alloying scheme at lower terrace is dominated by direct-exchange between Zn step adatom and the Cu atom underneath. The alloying at the middle terrace is dominated by the wave deposition mechanism and deep confinement of Zn adatom. References [1] Studt, F. et al., ChemCatChem 7 (7), 1105-1111, 2015. [2] Kattel, S. et al., Science 355 (6331), 1296, 2017. [3] Vandermause, J. et al., Npj Comput. Mater 6 (1), 20, 2020. Keywords: Cu-Zn alloy, molecular-dynamics, density functional theory, machine-learning Share Link | Plain Format | Corresponding Author (Harry Handoko Halim)

45	CHEMISTRY AND MATERIAL SCIENCES	ABS-132
Preparation and characterizations liquid crystal composites between methyl metacrylate with diacrylate resin of 2-methyl-1,4-phenylene bis(4-(3-(acryloyloxy)propoxy)benzoate) Afrizal (a*), Setia Budi (a), Rizky Fauziah Hanum (a), and Fitri Nulandari (a) a) Department of Chemistry Faculty Mathematics and Natural Sciences, Universitas Negeri *afrizal[at]unj.ac.id Abstract Liquid crystal composites is a material made from monomer liquid crystal with other material. This composites very useful because combine good properties each material for many applications. The diacrylate resin of 2methyl 1,4phenylene bis(4(3(acryloyloxy)propoxy)benzoate) is one of the liquid crystal that combined with monomer methylmetacrylate using casting solution. Process casting solution of that materials using variation weight procentage each materials. Result of casting solution was photopolymerized using preparate glass to make a thin layer polymer. Characterizations thin layer polymer liquid crystal diacrylate resin with MMA using instrumentations FTIR for identify of chemical group functions molecules. FTIR spectrum showed peak at 1155 until 1160 for identifications stretching vibration of COC in ester molecule and 2925 and 2960 cm for identify stretching vibration of CH3. Its band for identify bond formation between MMA with diacrylate resin. Diffractogram XRD showed thin layer polymer of PMMA diacrylate resin has amorphous properties, because there are not sharp peak diffraction at 2&#952- 16.33, 24.02, 44.68, and 72.54. this is indications that thin monomer methylmetacrylate blending perfect with diacrylate resin. Therefore analysis morphology of thin layer polymer PMMA-diacrylate resin homogen in some regions but in a little surface seen aglomeration of polymer. Keywords: liquid crystall, thin layer polymer Share Link | Plain Format | Corresponding Author (Afrizal Afrizal)

46	CHEMISTRY AND MATERIAL SCIENCES	ABS-143
Sulfuric Acid-Free Synthesis of Electrochemically-Exfoliated Graphene (EEG) as An Eco-Friendly Counter-Electrode Material for Dye-Sensitized Solar cells Nenden Fauziah (a,b,c), Nadiatus Silmi(a,b), Fairuz Gianirfan Nugrohod,(e), Kemal Lesmana Hidayat Putra (b), Brian Yuliartoe (f), Rahmat Hidayat (e,g), Veinardi Suendo(b,e)(*) (a)Doctoral Program of Chemistry, Faculty of Mathematics and Natural Sciences, Department of Chemistry, Institut Teknologi Bandung, Bandung 40132, Indonesia (b)Division of Inorganic and Physical Chemistry, Institut Teknologi Bandung, Bandung 40132, Indonesia- (c)Chemistry Division, Universitas Garut, Garut, Indonesia (d)Master^s Program in Nanotechnology, Graduate School, Institut Teknologi Bandung, Bandung 40132, Indonesia (e)Research Center for Nanosciences and Nanotechnology, Institut Teknologi Bandung, Bandung, Indonesia (f)Advanced Functional Materials (AFM) Laboratory, Department of Engineering Physics, Institut Teknologi Bandung, Bandung 40132, Indonesia. (g)Division of Magnetic and Photonic Physics, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Bandung, Indonesia (*)Corresponing author e-mail: vsuendo[at]chem.itb.ac.id Abstract A more environmentally friendly synthesis route of electrochemically-exfoliated graphene (EEG) materials through electrochemical exfoliation can be achieved without sulfuric acid as the exfoliating medium. Therefore, the ammonium sulfate solution was adopted as a substitute for sulfuric acid during the electrochemical exfoliation. As a result, the exfoliation process took twice as long as with the sulfuric acid. The morphology and chemical constituents were analyzed using SEM-EDS and observed that all EEGs have amorphous morphology with a homogeneous chemical distribution. Raman analysis shows that the ammonium sulfate exfoliated EEG (EEG_B) has more defects than the sulfuric acid exfoliated EEG (EEG_A). Therefore, the PANI-EEG_B composite performs better than the PANI-EEG_A composite material when applied as a counter-electrode in DSSC. The performance of PANI-EEG_B (&#61544- = 1.71%) as a counter-electrode in DSSC is even better than the Pt counter-electrode (&#61544- = 1.49%). Thus, applying EEG_B with PANI as an electrode composite in CE leads to a higher-performing and more eco-friendly DSSC. Keywords: Ammonium sulfate, counter-electrode materials, Dyes-sensitized solar cells, Electrochemically-exfoliated graphene, Exfoliating medium, Sulfuric acid. Share Link | Plain Format | Corresponding Author (Nenden Fauziah)

47	CHEMISTRY AND MATERIAL SCIENCES	ABS-144
Investigation Influence of Hierarchical and Impregnation Mixed Metal Fe-Co on Ludox-ZSM5 Structure with Rietveld Refinement of Diffraction Pattern Lisa Adhani (a,b), Bambang Heru Susanto (a), Mohammad Nasikin (a*) (a) Department of Chemical Engineering, Faculty of Engineering, Universitas Indonesia, 16424 Depok, West Java, Indonesia (b) Department of Chemical Engineering, Faculty of Engineering, University of Bhayangkara Jakarta Raya, 17143 Bekasi, West Java, Indonesia Corresponding author: *mnasikin[at]che.ui.ac.id Abstract The modification structure of synthetic zeolite for catalyst applications in industrial processes is currently in great demand. This is because Zeolite has unique framework structural properties and does not damage easily even at high temperatures. This study investigates the effect of hierarchical treatment and impregnation of ZSM-5 using Rietveld refinement (search and match) analysis on sample diffraction patterns from X-Ray Diffraction with reference diffraction patterns (Crystallography Information File) using MAUD (Material Analysis Using Diffraction) software. The results of this analysis found that the hierarchical treatment and impregnation of the mixed metal Fe-Co on LudoxZSM-5 caused a phase change. The initial phase of LudoxZSM-5 is similar to the orthorhombic MFI type, which undergoes a phase change after the hierarchy is applied, i.e. it approaches the structure system of the MCM-68 type, which then approaches the FER type crystal phase (ZSM-35) after receiving the impregnation-calcination treatment. Keywords: Ludox, ZSM-5, Hierarchy, X-Ray Diffraction, MAUD, Rietveld refinement Share Link | Plain Format | Corresponding Author (Lisa Adhani)

48	CHEMISTRY AND MATERIAL SCIENCES	ABS-148
MAGNETIC-BIOCHAR NANOSORBENT BASED ON OIL PALM EMPTY FRUIT BUNCHES (OPEFB) FOR CHROMIUM (VI) IONS REMOVAL Dwi Catur Cahyaningsih, Dara Chairunnisa, Mutmainna, Shanny Fridarima, Lailatul Ghonimah, Nila Tanyela Berguis* Universitas Pertamina Abstract Magnetic biochar nanosorbent as a bio-adsorbent for remediation of chromium metal waste has been successfully synthesized from biochar composites based on oil palm empty fruit bunches (OPEFB) modified magnetite (\(Fe_3O_4\)).The OPEFB biochar was synthesized using the pyrolysis technique at \(600^\circ C\) with a yield of \(34.8\%\). The \(Fe_3O_4\) nanoparticles on the biochar surface allow the adsorbent to be separated easily and quickly from the solution. The characteristics of the synthesized OPEFB, biochar, \(Fe_3O_4\) and magnetic biochar nanosorbent were analyzed using Fourier Transform Infrared Spectroscopy (FTIR) and X-ray Diffraction (XRD), also adsorption test using the Freundlich and Langmuir isotherm adsorption models. The IR spectrum of the magnetic-biochar nanosorbent shows the stretching vibration of the O-H bond of the hydroxyl group, the vibration of the C=C strain on the aromatic ring, the C-H bond of the aliphatic group in aromatic substitution and the characteristic peak of Fe-O strain. The XRD diffractogram results show that the resulting magnetic-biochar crystallographic pattern has peaks at \(2\theta\) = \(30.1^\circ\), \(30.5^\circ\), and \(43.1^\circ\) with the designation of fields (220), (311), and (400). The analysis results show that the Freundlich model better at describing the adsorption process of chromium (VI) ions by magnetic-biochar nanosorbent with an \(R^2\) value of 0.7153. The analysis results show that the Freundlich model is better at describing the adsorption process of chromium (VI) ions by magnetic biochar nanosorbent with an \(R^2\) value of 0.7153, compared to the Langmuir model which has an \(R^2\) value of 0.3518. Keywords: biochar, \(Fe_3O_4\), magnetic-biochar nanosorbent, adsorption, chromium (VI) ions Share Link | Plain Format | Corresponding Author (Dwi Catur Cahyaningsih)

49	CHEMISTRY AND MATERIAL SCIENCES	ABS-149
Effect of voltage on morphology of biopolymer-based electrospun fiber from Starch Asti Sawitri (1), Dian Ahmad Hapidin (1), Neni Surtiyeni (1), Arie Wibowo (3), and Khairurrijal Khairurrijal (1,2,4,*) (1)Department of Physics, Faculty of Mathematics and Natural Sciences, Bandung Institute of Technology, Indonesia. (2)University Center of Excellence - Nutraceutical, Bioscience and Biotechnology Research Center, Bandung Institute of Technology, Indonesia. (3)Departement of Material Science and Engineering, Faculty of Mechanical and Aerospace Engineering, , Bandung Institute of Technology, Indonesia. (4)Department of Physics, Faculty of Sciences, Sumatera Institute of Technology, Indonesia. * Corresponding author: krijal[at]fi.itb.ac.id Abstract The synthesis of starch nanofibers with the electric spinning technique produces nanofibers with high porosity characteristics, a very high specific surface area, and biocompatible, biodegradable, and bioabsorbable properties. In this study, fiber synthesis was carried out by varying the voltage in the spinning process. The morphology of the formed fiber is cylindrical, with several beads formed. The size of the beads increases with increasing voltage. The voltages parameter produces an insignificant difference in diameter. The fiber diameter distributions obtained at voltages of 13, 15, and 17 kV were 1231.08+-11.59 nm, 1121.18+-273.28 nm, and 1082.54+-291.33 nm, respectively. Keywords: starch, fiber, electrospinning, biopolymer, voltage, morphology Share Link | Plain Format | Corresponding Author (Asti Sawitri)

50	CHEMISTRY AND MATERIAL SCIENCES	ABS-156
Prediction CEC Value of Soil Using pH Parameters, Organic Carbon and Exchangeable Alumunium (Al-dd) Elmus Rahma* (a), Suprapto (a) (a) Chemistry Department, Sepuluh November Institute of Technology (ITS), ITS Campus : Sukolilo Street, Surabaya 60111, Indonesia * newelmusrahma[at]gmail.com Abstract Cation Exchange Capacity (CEC) is one of the soil test parameters that shows the ability of the soil to hold exchangeable cations. CEC is the ability of the soil to hold positively charged ions, which is an important indicator of soil fertility. CEC is an important parameter because it affects soil structural stability, nutrient availability, pH and reaction to fertilizers. In Indonesia, generally the determination of CEC is carried out using the Ammonium Acetate method by shaking/extracting, but recently the development for determining CEC by means of Percolation has been carried out. However, both in the extraction and percolation methods, CEC testing is a difficult test, requires a lot of time and process, and uses a lot of solvents where the remaining solvent will be a waste. Another difficulty in this test is the precision results are not good compared to other parameters in soil fertility. In this study, predictions of CEC values will be made using linear regression with several parameters including pH H2O, Organic Carbon and Exchangeable Alumunium (Al-dd) where these three parameters can be analyzed easily in various soil laboratories. In this study, verification of the two CEC methods will also be carried out so that the test results can be accounted for. The results of the CEC test then compared using a t-test between the two methods to find out whether the two methods were significantly different. Keywords: CEC, Soil, pH, Organic Carbon, Al-dd Share Link | Plain Format | Corresponding Author (Elmus Rahma)

51	CHEMISTRY AND MATERIAL SCIENCES	ABS-162
Effect of Heteroatoms of Asphaltene Structure Models on Molecular Aggregation Behavior Muhammad Fahri Afiki (a), Mia Ledyastuti (a*) a) Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung Jalan Ganesha 10, Bandung 40132, Indonesia *mia.ledyastuti[at]itb.ac.id Abstract One of the problems in the petroleum industry is the formation of asphaltene molecular aggregates. Asphaltene is a petroleum fraction in the form of polycyclic aromatic compounds. Computational modeling can be used to investigate the mechanism of asphaltene molecular aggregation. An asphaltene molecule has been modeled using B3LYP level of theory with DFT-D4 dispersion correction for dimers and def2-SVP basis set. The asphaltene molecule is modeled as a polycyclic aromatic compound with variations of N, O, and S heteroatoms. The modeling is carried out on the monomer and dimer of the asphaltene molecule. The tendency of asphaltene monomer molecules to form dimers is analyzed by calculating the electrophilicity index (&#969-) which is a function of chemical hardness (&#951-) and electronic chemical potential (&#956-) of the molecule. The result shows that the presence of the N atom in a certain position increases the electron density in the aromatic ring. Meanwhile, the presence of O and S atoms in the aliphatic tail causes the electron density to shift towards each of these heteroatoms. The substitution of the carbon atom connecting the aromatic ring and aliphatic chain by the three heteroatoms causes the polarity of the asphaltene molecule to increase. Keywords: asphaltene, DFT, heteroatom Share Link | Plain Format | Corresponding Author (Muhammad Fahri Afiki)

52	CHEMISTRY AND MATERIAL SCIENCES	ABS-163
Immobilization of \(STARGEN^{TM}002\) on Amine-Glutaraldehyde Modified Silica and Its Enzymatic Properties Zico Daniel Despen Sihombing (a), Vilda Afrilia Dwi Nanda (a), Handajaya Rusli (a*), Ihsanawati (b), Dessy Natalia (b) (a) Analytical Chemistry Research Division, Faculty of Mathematics and Natural Sciences, Bandung Institute of Technology. Jl. Ganesha 10, Bandung, Indonesia. *handajaya[at]itb.ac.id (b) Biochemistry Research Division, Faculty of Mathematics and Natural Sciences, Bandung Institute of Technology. Jl. Ganesha 10, Bandung, Indonesia. Abstract \(STARGEN^{TM}002\) is an industrial enzyme widely used to hydrolyze starch, producing glucose, maltose, and maltodextrin. The usage of \(STARGEN^{TM}002\) in the starch processing industry has limitation due to its stability and non-reusable properties. Therefore, enzyme immobilization has become a powerful tool to overcome these problems. The purpose of this study was to immobilize \(STARGEN^{TM}002\) to amine-glutaraldehyde modified silica and determine the enzymatic characterization. A silica was synthesized using the Stober method and further modified with propylamine and propyldiethylenetriamine. Both modified silica were then used to immobilize \(STARGEN^{TM}002\) using glutaraldehyde as a crosslinker. All activities of free and immobilized enzymes towards soluble starch were carried out using the 3,5-dinitrosalicylic acid (DNS) method, while the amount of proteins was determined using the Bradford method. The optimum pH of free and immobilized enzymes were 6.5 at an optimum reaction temperature of 60\(^{o}C\) with 2%-w/v of soluble starch. The immobilized enzyme still exhibited the activity up to the 7\(^{th}\) use with the remained specific activity of 38 and 41% for silica propylamine and silica propyldiethylenetriamine, respectively. At optimum conditions, the specific activity of the free enzyme was 7.59 U/mg. However, the immobilized enzyme by silica propylamine and by silica propyldiethylenetriamine was 8.57 and 9.31 U/mg, respectively, indication for increasing the enzyme stability and activity. Taken together, the immobilized \(STARGEN^{TM}002\) with the amine-glutaraldehyde modified silica are promising for industrial applications. Keywords: Immobilization- \(STARGEN^{TM}002\)- modified silica- propylamine- propyldiethylenetriamine- glutaraldehyde Share Link | Plain Format | Corresponding Author (Zico Daniel Despen Sihombing)

53	CHEMISTRY AND MATERIAL SCIENCES	ABS-169
rbcL gene as a tool for DNA barcoding to identify marine diatom from Lampung Bay and Seribu island Elfira Rosa Pane, Yanti Rachmayanti, Zeily Nurachman Program studi Doktor Kimia Institut Teknologi Bandung Abstract The focus of this study was to identify a region in the rbcL gene that can be utilized as a barcode to identify diatoms in the waters of Lampung Bay and the Thousand Islands. The methods employed included sampling, isolating, cultivating diatoms, examining diatom morphology, DNA isolation, polymerizing the rbcL and 18S genes, and strain classification through phylogenetic trees. Thirteen diatom strains were successfully grown and their DNA was isolated as a result of this investigation. Genetic identification based on the rbcL gene and 18S V4, followed by phylogenetic analysis, revealed that the SELBA1 strain belonged to the same clade as Serratifera takanoi- EPI1 strain belongs to the same lineage as Entomoneis sp species- ALBA1 strain belongs to the genus Actinocyclus- LLBA1 strain and Lauderia annulata belong to the same lineage- HLBA1 strain belongs to the same lineage as the Halamphora aponina strain- NLBA1 strain is classified as monophyletic with Halamphora coffeaeformis- TMA2 strain is classified in one clade with Cyclotella striata, NLA1 and PBI1 strains were classified with Navicula salinicola, NLBA2 strains were monophyletic with Navicula salinarum- TMGS1 strain was classified as one clade with Nitszchia inconspicua, PBI2 strain was classified as monophyletic with Nitszchia supralitorea, and TMA3 strain was classified as monophyletic with Psammodictyon panduriforme. There was a classification discrepancy between the two genes in the NLBA1 strain because the size of the 18S V4 gene in this strain was too short, hence the rbcL gene was utilized to identify this strain Keywords: Diatom, Indonesian marine, rbcL gene, 18S V4, phylogenetic tree. Share Link | Plain Format | Corresponding Author (Elfira Rosa Pane)

54	CHEMISTRY AND MATERIAL SCIENCES	ABS-170
Carbon Dioxide Adsorption and Conversion to Formate on Cu(100) and Zn/Cu(100) Fikri Akbar Mubarok, Wa Ode Nur Fitriah Rajaelo, Atthar Luqman Ivansyah, Fahdzi Muttaqien Computational Science, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung Jalan Ganesha No.10, Bandung, West Java, 40132, Indonesia Abstract The mechanism of formate synthesis from CO2 hydrogenation on clean and Zn-modified Cu(100) was studied by employing density functional theory (DFT) calculations. We performed van der Waals correction to avoid the weak interaction between CO2 and copper surfaces. Our study showed that the binding energy of CO2 on copper surfaces is well defined by using optB86b-vdW functional rather than PBE. The CO2 is physisorbed on Cu(100) with an adsorption energy of -0.22 eV. The activation energy of CO2 hydrogenation to formate on clean Cu(100) is 0.32 eV. A single Zn dopant can reduce the activation energy of CO2 hydrogenation by only 0.03 eV compared to clean Cu(100). While the single Zn adatom is unaffected, the activation energy of CO2 hydrogenation is 0.003 eV higher than on clean Cu(100). Keywords: CO2 hydrogenation, Eley-Rideal mechanism Share Link | Plain Format | Corresponding Author (Fikri Akbar Mubarok)

55	CHEMISTRY AND MATERIAL SCIENCES	ABS-174
High Dimension Neural Network Potential Implementation for FeS Optimization Muhammad Rizky Rahman (a*), Iqbal Lafifa Zulfa (a), Ari Sulistyowati (a), Dr. Atthar Luqman Ivansyah (a), Fahdzi Muttaqien, Ph.D (a) a) Bandung Institute of Technology Jalan Ganesha 10, Bandung 40132, Indonesia * 20920305[at]mahasiswa.itb.ac.id Abstract Iron sulfide (FeS) is of interest due to their potential usage in a variety of industries, including energy storage, catalysis, and environmental remediation. FeS is a Metal-Insulator Transition (MIT) material in which its electronic properties can be modified as initial temperature treatment. FeS take a form P62c when it hit temperature below 416 K and change to P63/mmc when the temperature raise above it. Nevertheless, since a stoichiometric ratio is challenging to attain, multistep methods are needed to synthesize FeS. In this study, we employ artificial neural network (ANN) based on Behler-Parinello approach to investigate the phase changes of FeS at 300 - 550 K. Currently, we try to elucidate the best multilayer perceptron (MLP) ANN structure to construct adequate atomic interaction potential of FeS. The potentials are constructed from more than 4000 database structures, which include pristine and defected structures. We obtain that 2 hidden layers MLP with 20 nodes in each shows fine training and testing set error. We do force minimization of particular FeS structure using ANN atomic potential. We obtain excellent results as no overlapping Fe-S bond length in the final structure and no odd energy change. Keywords: FeS, Molecular Dynamics, Artificial Neural Network Share Link | Plain Format | Corresponding Author (Muhammad Rizky Rahman)

56	CHEMISTRY AND MATERIAL SCIENCES	ABS-176
Molecular Modeling and Expression of Multimeric Bann-RBD Fusion Protein in Pichia pastoris as a COVID-19 Vaccine Candidate Ozi Jumadila (a), Muhammad Dzul Fakhri (a), Fernita Puspasari (a), Fifi Fitriyah Masduki (a), Sari Dewi Kurniasih Indrawan (a), Keni Vidi Laseris (b), Ihsanawati (a), Dessy Natalia (a*) (a) Institut Teknologi Bandung, Indonesia (b) University of Helsinki, Finland *dessynatalia[at]itb.ac.id Abstract The COVID-19 pandemic caused by the transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has a wide impact on health, economy, and other sectors. Various vaccine platforms have been developed and are being administered worldwide to provide protection. Subunit protein vaccines are one of the most widely developed COVID-19 vaccine candidates. The receptor binding domain (RBD) of spike protein has been used as an antigen as it can stimulate the immune system to produce neutralizing antibodies that can inhibit the interaction of the virus with ACE2. Several studies have shown that dimeric, trimeric, and multimeric RBD produce higher neutralizing antibodies than monomeric RBD. In this study, we have developed a multimeric RBD as a protein fusion of RBD and &#946--annulus (Bann) from tomato bushy stunt virus (TBSV). Pichia pastoris X-33 was chosen as an expression host because it can secrete protein efficiently and has a post-translational modification system. The molecular modeling of the Bann-RBD protein shows a trimeric structure with Bann being at the core and RBD being displayed on the surface. P. pastoris X-33-pPICZ&#945-A-Bann-RBD has been successfully constructed. SDS PAGE analysis of the Bann-RBD protein expressed in P. pastoris X-33 showed several protein bands which are predicted to be monomer, dimer and trimer of glycosylated Bann-RBD. Further characterization indicated that the resulted recombinant Bann-RBD can recognize strongly an antibody of COVID-19 in positive patient serum. Taken together, this results indicate that the recombinant Bann-RBD produced in P. pastoris X-33c could be used in the development of COVID-19 candidate vaccine. Keywords: COVID-19- multimeric protein- RBD- subunit vaccine- &#946--annulus Share Link | Plain Format | Corresponding Author (Ozi Jumadila)

57	CHEMISTRY AND MATERIAL SCIENCES	ABS-178
Optimization of Biosurfactant Condition by Bacillus sp. ALP D1 Using RSM. Hanisa Damayana (a,b), Nurhasanah (a,b) 1. Department Chemistry, Faculty Mathematics and Natural Science, University of Lampung, Jl. Soemantri Brojonegoro No. 01, Bandar Lampung, 35154, Indonesia. 2. Research Group Biochemistry , Department Chemistry, Faculty Mathematics and Natural Science, University of Lampung, Jl. Soemantri Brojonegoro No. 01, Bandar Lampung, 35154, Indonesia. Abstract Biosurfactants are amphiphilic compounds that act as surface active agents because it consist of two parts, hydrophilic groups and hydrophobic side. Both parts make them able to work between liquids with different polarities such as water and oil which allow them to reduce the surface tension. The nature of these biosurfactants makes them widely applied in various fields such as agriculture, industries, detergent, pharmaceutical, cosmetics, bioremediation, and others. This study aims to find the optimum condition of biosurfactant from Bacillus sp. ALP D1 used Response Surface Method Central Composite Design (RSM-CCD). The methods used rejuvenation of bacterial culture, optimization of biosurfactant carbon source (POME) concentration by 3%, 4%, 5% and production time (12 h until 120 h in the range every 12 h) at the same time that it do research directly, while nitrogen source (NaNO3) concentration by 1%, 2%, 3%, pH (6, 7, 8), salinity by (3%, 5%, 7%), it was carried out using RSM design, and the last produce biosurfactants. Determination of biosurfactant activity is done by measuring emulsification activity. The results of this study are RSM design proposed 14 experimental designs that can be undertaken to find the optimum condition of biosurfactant. The result of CCD-RSM Design is polynomial equation: Y1 = 48.6 + 3.35125 X1+ 0.13625 X2 + 2.55125 X3 - 2.98375X1X2 + 1.54625 X1X3 - 2.18375 X2X3 + 7.82125 X21. The optimum condition of biosurfactant from Bacillus sp. is seen by the value of emulsification activity obtained after the experiment design. The highest emulsification activity (IE24) was obtained 69.44% at 3% POME, 72 h, 3% NaNO3 conditions, 6 pH, and 7% of salinity levels, which indicates the optimal condition of the biosurfactant bacteria Bacillus sp. ALP D1. Keywords: Biosurfactant, Bacillus sp., RSM-CCD, Parameter optimization, Emulsification index Share Link | Plain Format | Corresponding Author (Hanisa Damayana)

58	CHEMISTRY AND MATERIAL SCIENCES	ABS-184
Starch-graft-poly((2-Dodecen-1-yl)succinic anhydride): studies of microwave-assisted synthesis, characterizations, and its potential as bioplastic materials Natalia Devita Purnama and Rachmawati Rachmawati Inorganic and Physical Chemistry Division, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Jalan Ganesha 10, Bandung 40132, West Java, Indonesia Abstract Starch is a natural polymer which can be applied as a potential bioplastic material. However, due to its low plasticity and mechanical properties, starch needs to be modified chemically, such as involving a graft copolymerization method. In this research, microwave-assisted synthesis of graft copolymer of starch was conducted via free radical polymerization. For this reaction, (2-Dodecen-1-yl)succinic anhydride (DDSA) was used as a monomer and cerium(IV) ammonium nitrate (CAN) as an initiator. Several factor were varied, such as the ratio of DDSA and CAN, polymerization time, and microwave power, to study their effects on the values of grafting percentage (%G) and grating efficiency (%E). The resulting starch-g-poly(DDSA) was characterized using Fourier-Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD), and Thermogravimetric analysis (TGA). The optimum grafting condition resulted in a graft copolymer with %G of 42% and %E of 86%. This was obtained for a theoretical degree of polymerization of 5, starch and CAN mass ratio of 3:1, 200 W power, and 25 minutes polymerization time. The FTIR spectra of the copolymer products showed characteristic peaks at 2847-2914 cm-1 and 1313-1421 cm-1 which corresponded to C-H methyl and methylene groups, and 1686 cm-1 from the C=O groups from DDSA. XRD diffractograms showed that there were broad peaks at 2 theta of 19.8 and 27.9 degrees, while TGA thermograms showed that the higher the %G, the lower the onset temperature of the thermal degradation. The copolymer products were further mixed with poly(vinyl alcohol), and casted as films using glycerol as a plasticizer. The highest elongation and tensile strength obtained for starch-g-poly(DDSA)/PVA film was 216.5% and 3.91 MPa respectively, which used starch-g-poly(DDSA) with %G of 42%. Keywords: (2-Dodecen-1-yl)succinic anhydride, bioplastic, cassava starch, cerium(IV) ammonium nitrate, graft copolymerization Share Link | Plain Format | Corresponding Author (Natalia Devita Purnama)

59	CHEMISTRY AND MATERIAL SCIENCES	ABS-197
Revealing Lithium Prospects in Geothermal Hot Springs on Bangka Island-Indonesia Using The ICP-OES Method Asep Rohiman1,2- Kurnia2- Dida Yurnaldi2- Ronaldo Irzon2- Henry Setiyanto1-Robeth Viktoria Manurung3-and Muhammad Bachri Amran1 1 Analytical Chemistry Research Group, Faculty of Mathematics and Natural Sciences, Bandung Institute of Technology, Jl. Ganesha, 10, Bandung, 40132, Indonesia. 2 Center of Geological Survey, Geological Agency, Ministry of Energy and Mineral Resources Jl. Diponegoro No.57, Ged. AF. Lasut VII, Bandung 40144, Indonesia. 3 Research and Innovation Agency (BRIN) Republic of Indonesia, Kawasan Puspiptek Building 820, Tangerang, Banten, Indonesia. Abstract The growth of lithium utilization in the portable electronic device industry, electric vehicles, medical demands, and defense sectors is likely to continue. As a result, in order to fulfill market demand, the availability of lithium deposits must be enhanced. As a result, it is critical to research the sources of lithium deposits in Indonesia. Indonesia is an archipelagic country situated at the meeting point of four global plates: the Eurasian, Indo-Australian, Pacific, and Philippine plates. This is a one-of-a-kind and extremely unusual occurrence across the globe. The collision of these plates led to the production of geological resources such as oil and gas basins, mineral resources, geothermal potential, groundwater potential, and so on. Furthermore, Indonesia is one of the nations crossed by the ring of fire, with several hot springs and lithium-containing brine. However, research on the potential of lithium in Indonesia is still restricted. As a result, this study conducted investigations and analyses on the probable sources of lithium in hot springs near the Bangka archipelago, namely Nyelanding, Permis, and Kretak hot springs. The samples from the hot springs were examined using ICP-OES. Volumetric and gravimetric techniques were used for anion analysis. Based on data analysis, Permis hot springs have the highest lithium content, with a concentration range of around 2 ppm to 3 ppm. The plotting of the composition of the Cl-SO4-HCO3 anions from Permis hot water samples reveals that the hot springs are of the mature water type with abundant chloride conditions. This suggests that volcanic activity has a minimal effect on the hot springs. While the Kretak and Nyelanding hot springs are of the peripheral water type, with a dominant HCO3 percentage, this type indicates that the geothermal source is in a remote place and the water moves horizontally. A high HCO3 level implies that the rocks have been leached through or combined with HCO3-rich surface water. Keywords: energy, geothermal, hot springs, ICP-OES, lithium, potential Share Link | Plain Format | Corresponding Author (Asep Rohiman)

60	CHEMISTRY AND MATERIAL SCIENCES	ABS-204
The Synthesis of Dehydrozingerone (DHZ) in 1-Decyl-3-Methylimidazolium Bromide ([DMImBr]) Ionic Liquid Medium Utilizing Microwave Assisted Organic Synthesis (MAOS) Method Annisa Mustika Pertiwi (a), Deana Wahyuningrum (a)* (a) Department of Chemistry, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung Jalan Ganesha 10, Bandung 40132, Indonesia *deana[at]itb.ac.id Abstract Dehydrozingerone (DHZ), 4-(4-hydroxy-3-methoxyphenyl)-3-buten-2-one, is a natural compound that can be isolated from the rhizome of ginger (Zingiber officinale) and has attracted the attention of many researchers, especially in the field of medicinal chemistry. DHZ and its derivatives have a wide range of bioactivities, including antioxidants, anticancer, antimalarial, antidepressant, antifungal, and many others. DHZ can be synthesized from vanillin and acetone by cross-aldol (Claisen-Schmidt) condensation, yet its conventional synthesis needs a 24-hour time and generates a low yield percentage. Green chemistry aspects such as efficiency, atom economy and low energy factor are important aspects that should be considered to synthesize DHZ. In this research, the synthesis of DHZ from vanillin and acetone in 1-decyl-3-methylimidazolium bromide ([DMIMBr]) ionic liquid media was carried out using the Microwave Assisted Organic Synthesis (MAOS) method as one of the synthesis methods that fulfill green chemistry aspects. Product characterization was carried out using melting point tests, TLC, FTIR, 500 MHz (1H) and 125 MHz (13C) NMR instrumentation. The DHZ product with the best yield was synthesized from vanillin and acetone (1:10, mol/mol) in 10% NaOH and 10% DMIMBr using MAOS (closed vessel) for 120 minutes (50 oC, 300 W) to produce a product in the form of a bright yellow solid of 60.90% yields with a melting point range of 128-129oC. Keywords: Dehydrozingerone- Ionic Liquid- MAOS- Green Chemistry Share Link | Plain Format | Corresponding Author (Annisa Mustika Pertiwi)

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