Indonesia is one of the largest palm oil-producing countries in the world. The results of palm oil processing produce a lot of waste, such as oil palm empty fruit bunches (OPEFB). The utilization of OPEFB in Indonesia is minimal, so it needs further development. OPEFB has a very high α-cellulose content, so that it can be used as raw material for manufacturing cellulose acetate. Making cellulose acetate from OPEFB consists of three main steps: delignification, bleaching, and acetylation. This study aims to compare the effects of the concentration of NaClO2 or H2O2 in the bleaching process on the physical properties of cellulose acetate from OPEFB. In the delignification process, 100 mesh-sized OPEFB powder is reacted with 5% sodium hydroxide (NaOH) at 100oC for 2 hours. The residue from deliglinfication was washed using distilled water until pH 7, filtered using filter paper, and dried using an oven at 50oC. The next step is the bleaching process using NaClO2 or H2O2 with concentration variations (1%, 2%, 3%, 4% and 5%). The bleaching process was carried out at 90oC for 1.5 hours. After filtration, the bleached residue was washed using distilled water until pH 7, filtered using filter paper, and dried using an oven at 50oC. After the bleaching process, α-cellulose powder was produced. The next step is acetylation, containing three main steps. The first step is the reaction between α-cellulose powder with acetic acid (CH3COOH) and sulfuric acid (H2SO4) at 40oC for 1.5 hours to perform activation. The second step is the addition of anhydrous cellulose in a ratio of 1:10 and mixed at 40oC for 1.5 hours. The third step is the addition of distilled water, acetic acid, and sodium acetate (CH3COONa) at 40oC for 5 minutes. Then, followed by filtration, the residue was washed using distilled water and methanol until pH 7 and dried at 50oC. The best result is using NaClO2 as a bleaching agent with a concentration of 2%, resulting in cellulose acetate yielding 98.85%, density of 1.954 g/mL, and L value of 91.897 for colorimetric test results. The density and L-value were close to commercial cellulose acetate (Sigma Aldrich). From the results of FTIR analysis, it can be concluded that the acetylation of α-cellulose into cellulose acetate has been successful, as evidenced by the formation of carbonyl groups (C=O).
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