Biomass upgrading through acid–base catalysis

The development of economic processes for the production of liquid fuels from biomass requires large investments. Therefore, the search of new catalysts for the enhancement of both the yields and the quality of biofuels is the key to improve the efficiency and reduce costs.In this scenario, acid and base catalysis plays a crucial role in most of the processes used for the production of biofuels, such as the transesterification of vegetable oils with methanol in the biodiesel process and the hydrolysis of cellulose to fermentable sugars for bioethanol production.An overview of some of the technologies currently used commercially or tested at pilot and laboratory scale, based on acid and base catalysts, is presented in this paper.