THE EFFECTS OF NaClO₂ AND H₂O₂ AS BLEACHING AGENTS IN THE SYNTHESIS OF CELLULOSE ACETATE FROM OIL PALM EMPTY FRUIT BUNCH

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 100^oC 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 50^oC. 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 90^oC 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 50^oC. 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 40^oC 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 40^oC for 1.5 hours. The third step is the addition of distilled water, acetic acid, and sodium acetate (CH₃COONa) at 40^oC for 5 minutes. Then, followed by filtration, the residue was washed using distilled water and methanol until pH 7 and dried at 50^oC. 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).