BIOLOGICAL CONVERSION OF ALGEFIBER? (SEAWEED SLUDGE) TO CARBOXYLIC ACIDS FOR CHEMICAL UPGRADING TO HIGHER ALCOHOLS LIQUID BIOFUEL

摘要

The concern on biofuel production from renewable resources has increased globally. Among different approaches to produce biofuels, the MixAlco~(TM) process is an innovative technology, which converts any biodegradable material into mixed alcohol fuels through anaerobic digestion and chemical upgrading. In this study, using the MixAlco~(TM) process, carboxylic acids were produced from Algefiber? which is an alkaline-pretreated waste biomass from carrageenan processing (FMC Biopolymer). Carboxylic acids make up a platform of chemical intermediates, which can be converted in to mixed alcohol fuels and chemicals. Algefiber? was anaerobically digested using a mixed-culture of marine-derived microorganisms at two temperatures of 35°C (mesophilic) and 55°C (thermophilic) in bench scale batch fermentors. Further studies were done using leaching columns to simulate the fermentation under field conditions. Calcium carbonate and ammonium bicarbonate were added to maintain the pH of the fermentation by neutralizing the acids to their corresponding carboxylate salts. Iodoform was used as a methane inhibitor to suppress the methanogenesis. Mesophilic temperature gave a higher acid yield with higher percentage of longer chain organic acids. Acetic, propionic and butyric acids were prominent in the produced acid mixture. The produced carboxylate salts were dried and thermally decomposed to produce ketones.