Alkaline pretreatment of coconut husk fiber for cellulose production as an alternative bioethanol feedstock

Abstract

Coconut fiber is one of the biomass that being reported to contain high amount of cellulose and has potential to be converted into bioethanol. However, coconut fiber has to undergo pre-treatment process in order to remove lignin that hinder the access of cellulose. Therefore, the aim of this study is to evaluate cellulose production from coconut husk fiber via alkaline pre-treatment. Firstly, surface morphology of coconut fiber has been observed by Scanning Electron Microscope (SEM) and it showed the surface of pre-treated coconut fiber has rougher than coconut husk. The rougher surface indicates there is some disruption on the surface of coconut fiber due to alkaline pre-treatment. Next, the effect of alkaline pre-treatment parameters which are time reaction, NaOH concentration and temperature was examined by using One Factor at a Time (OFAT). The determination on holocellulose content during OFAT experiments was done by using Technical Association of the Pulp and Paper Industry T19m-54 method (TAPPI T19m-54 method). Based on OFAT experiments, the range of alkaline pretreatment parameters for highest holocellulose content was from 1% to 5% NaOH, temperature at 80 °C to 120 °C and time reaction from 30 minutes to 150 minutes. Lastly, cellulose analysis was done by using TAPPI T203 0M-93 method and the highest cellulose content for temperature is 97.15% at 110°C, response time is 93.78% at 90 minutes and NaOH concentration is 93.61% at 4%.