Catalytic Conversion of Various Biomass Feedstocks to Liquid Transportation Fuels

Abstract

This review of the author’s research introduces the catalytic reactions for the conversion of various biomass feedstocks to liquid transportation fuels, especially to liquid hydrocarbon fuels. Catalytic reactions in the following chemical processes were included: conversion of synthesis gas (obtained from the gasification of woody biomass) to liquid fuels (hydrocarbons and alcohols); conversion of vegetable oils to liquid hydrocarbons; conversion of algae oils to liquid hydrocarbons; and conversion of bioethanol to liquid hydrocarbons. Polymerization and hydrotreatment were two main catalytic technologies in these chemical processes. The polymerization reactions included Fischer-Tropsch synthesis, mixed alcohols synthesis, and ethylene oligomerization. Hydrotreatment reactions included cracking, isomerization, and deoxygenation. Metal catalysts, solid acid catalysts, and bifunctional catalysts containing metal and solid acid were developed for the reactions. Slurry reactor, fixed-bed flow reactor, and autoclave batch reactor were used according to the requirements of the various reactions. Active metal species, support effect, and balance between metal and solid acid in the bifunctional catalysts were discussed in the development of active catalysts. Using these catalysts and processes, various biomass feedstocks could be converted to hydrocarbon biofuels with the same chemical compositions as conventional petroleum-derived gasoline, diesel, liquefied petroleum gas (LPG) fuel, and jet fuel.