Optimization of Delignification in Pulping Process of Old Coconut (Cocus nucifera L.) Coir (Study of NaOH Concentration and Length of Cooking Time) Ika Atsari Dewi (a*), Azimmatul Ihwah (a), Alfi Ayuning Nur Kurniasari (a), Hendrix Yulis Setyawan (a)
(a) Universitas Brawijaya
Jalan Veteran Malang 65145, Indonesia
*ikaatsaridewi[at]ub.ac.id
Abstract
Old coconuts have main products, namely coconut meat and by-products consisting of coconut water, coconut shell, and coconut fiber. Coconut coir contains 75% fiber and 25% cork. The high value of fiber in coconut coir provides an opportunity to be utilized one of them in making paper. Coconut fiber has a cellulose content of 26.6% -43.44% and lignin of 29.4% -45.84%. Due to the high lignin content, delignification process should be carried out which can be done using Sodium Hydroxide (NaOH). This study aims to obtain the optimal point of addition of NaOH and cooking time to produce optimal cellulose and lignin levels in the delignification of the old coconut fiber pulping process. The research method uses Response Surface Methodology (RSM) with two factors and two optimized responses. The first factor is the concentration of NaOH consisting of 3 levels (20%, 25%, and 30%) w/v, the second factor is the cooking time consisting of 3 levels (90, 120, 150) minutes. The cooking process is done at a temperature of 100oC. The observed responses were lignin and cellulose levels. The process of testing the levels of lignin and cellulose levels was carried out using the Chesson Method. The preliminary results of the delignification process with higher concentrations (20%), namely the value of lignin levels lower than the concentration in previous studies using concentrations (15%). While the level of cellulose produced is higher, inversely proportional to the level of lignin, with the delignification process cellulose can be obtained more.
