Using Cassava Skin Extract to Adsorp Colouring Substances


The abundant amount of cassave skins in villages is not generally processed into a product with better value. Desiynuing explained that her researh on cassave skin extract as an absorbent  was based on the less benefits obtained from readily available cassava skins, in spite of 50% carbohydrate contained in its skin.The research steps were sample preparation, isolation, and sample extraction to obtain cellulose.

Isolating cellulose was done using soxhlet apparatus with ethanol and toluene as solvent in 1 to 2 ratio. The cassava skins were dried, blended and extracted using soxhlet apparatus for 5 hours. To remove the ethanol and toluene, the sample obtained in the previous process was heated and rinsed using hot water. Next cold and hot NaOH was used to remove the hemicellulose and lignin.The sample was the soaked in 0.5% NaOCL with solid NaOH addition so that the sample colour change into yellow-white. 16 grams of isolated sample was obtained from 60 grams of cassava skins.

Based on National Standards on Products, proper cellulose acetate contains 39.0% to 40.0% of acetyl. Through the absorbtion process towards the colouring substance, direct red and direct black, with variations in the length of time, 1 gram of adsorbent was dissolved in 100 ml of direct colouring substances in 200 ppm concentration. The research showed that the maximum adsorption capacity of cellulose acetate for direct red is during 90 minutes contact with adsorption efficiency of 44.82%. meanwhile, the adsorption efficiency of cellulose acetate for direct black was 32,5% during 45 minutes contact.

The incostant results was because a filtration process was not applied in measuring the solution absorbtion and it resulted in adsorbate residue affecting the absorbtion capacity. “The research revealed that cellulose acetate obtained from cassava skins is able to adsorp the direct colouring substance with increasing adsorption