The separation of phenolic compounds from bio-oil produced from pyrolysis of corncobs

Abstract

Corncob is an agricultural waste which has a potential to be utilized as a raw material for bio-oil. One of many processes to convert the agricultural waste (biomass) into bio-oil is pyrolysis. The pyrolysis process for this study was carried out using fixed bed pyrolysis reactor, performed under temperature of 500°C and 600°C with residence time of 4 seconds. The bio-oil was analyzed for its components content using Gas Chromatography-Mass Spectrometry (GCMS). The separation of phenolic compounds from bio-oil was done by a liquid-liquid extraction which carried out for 60 minutes using methanol 80% and chloroform as solvent at various extraction temperatures of 30°C, 40°C, 50°C, and stirring speeds of 200 rpm, 250 rpm, 300 rpm. Then, the extract phase and the raffinate phase were analyzed using Folin-Ciocalteu method. The aim of this study was to determine the effect of temperatures and stirring speeds of the liquid-liquid extraction to the distribution coefficient and the yield of phenolic compound. The result showed that the main component of bio-oil obtained is phenolic compounds. The highest distribution coefficient and the highest yield of phenolic compound were obtained at 50°C and 300 rpm. The highest yield was 66.31% and 58.9% obtained from pyrolysis process at 500°C and 600°C, respectively. Meanwhile, the highest distribution coefficient was 11.08 and 8.92 for pyrolysis at 500°C and 600°C.