Preparation and characterization of cellulose triacetate from cocoa pod husk

Abstract

The valorisation of agricultural residues into a high value-added product is necessary to respond to the global environmental concerns caused by the pollution of agricultural waste. The objective of this study was to shed light on a new value-added usage of cocoa pod husk (CPH) for the synthesis of cellulose triacetate (CTA). Alkaline treatment with sodium hydroxide (5 wt%) followed by bleaching process with (2 wt%) hydrogen peroxide was found effective for the extraction of cellulose from CPH. The percentage of cellulose obtained was 80.5% with a yield of 54%. The CTA was synthesised by a explore new way acetylation reaction in the presence of acetic acid, acetic anhydride, and sulphuric acid. The CTA obtained had a degree of substitution of 2.87 and a percentage of acetylated group of 43.8%, as determined by titration. The result of Fourier transform infrared spectroscopy showed the appearance of the stretching of the ester and the acetyl groups, indicating the formation of CTA. X-ray diffraction showed that the crystallinity index of CPH cellulose was 38.4%, while indicating the semi-crystalline nature of CTA produced. Scanning electron microscopy confirmed a change in the morphology of CTA after acetylation. X-ray energy dispersive analysis showed that the CTA was mainly composed of carbon and oxygen.