This paper provides an updated review on fast pyrolysis of biomass for production of a liquid usually referred to as bio-oil. The technology of fast pyrolysis is described including the major reaction systems. The primary liquid product is characterised by reference to the many properties that impact on its use. These properties have caused increasingly extensive research to be undertaken to address properties that need modification and this area is reviewed in terms of physical, catalytic and chemical upgrading. Of particular note is the increasing diversity of methods and catalysts and particularly the complexity and sophistication of multi-functional catalyst systems. It is also important to see more companies involved in this technology area and increased take-up of evolving upgrading processes. © 2011 Elsevier Ltd.

Review of fast pyrolysis of biomass and product upgrading

This critical review provides a survey illustrated by recent references of different strategies to achieve a sustainable conversion of biomass to bioproducts. Because of the huge number of chemical products that can be potentially manufactured, a selection of starting materials and targeted chemicals has been done. Also, thermochemical conversion processes such as biomass pyrolysis or gasification as well as the synthesis of biofuels were not considered. The synthesis of chemicals by conversion of platform molecules obtained by depolymerisation and fermentation of biopolymers is presently the most widely envisioned approach. Successful catalytic conversion of these building blocks into intermediates, specialties and fine chemicals will be examined. However, the platform molecule value chain is in competition with well-optimised, cost-effective synthesis routes from fossil resources to produce chemicals that have already a market. The literature covering alternative value chains whereby biopolymers are converted in one or few steps to functional materials will be analysed. This approach which does not require the use of isolated, pure chemicals is well adapted to produce high tonnage products, such as paper additives, paints, resins, foams, surfactants, lubricants, and plasticisers. Another objective of the review was to examine critically the green character of conversion processes because using renewables as raw materials does not exempt from abiding by green chemistry principles (368 references).

Conversion of biomass to selected chemical products

https://courses.washington.edu/cfr523/documents/Alonso2010CatalyticConversion.pdf

Catalytic conversion of biomass to biofuels

and Fuels Changzhi Li,† Xiaochen Zhao,† Aiqin Wang,† George W. Huber,†,‡ and Tao Zhang*,† †State Key Laborotary of Catalysis, iChEM (Collaborative Innovation Center of Chemistry for Energy Materials), Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China ‡Department of Chemical and Biological Engineering, University of WisconsinMadison, Madison, Wisconsin 53706, United States

Catalytic Transformation of Lignin for the Production of Chemicals and Fuels

Lignocellulosic biomass: a sustainable platform for the production of bio-based chemicals and polymers

Catalytic conversion of biomass-derived carbohydrates into gamma-valerolactone without using an external H2 supply.

A magnetic solid acid with mesoporous structure was synthesised for biomass saccharification and levulinic acid production. The catalyst shows improved performance for the hydrolysis of β-1,4-glucan and carbohydrate dehydration than a conventional solid acid. Moreover, the catalyst can be easily separated from the reaction residues with an external magnetic force.

Hydrolysis of biomass by magnetic solid acid

Conversion of Levulinic Acid and Formic Acid into γ-Valerolactone over Heterogeneous Catalysts

Cellulose is the major component of plant biomass, which is readily available and does not compete with the food supply. Hydrolysis of cellulose as the entry point of biorefinery schemes is an important process for chemical and biochemical industries based on sugars, especially for fuel ethanol production. However, cellulose not only provides a renewable carbon source, but also offers challenges to researchers due to the structural recalcitrance. 2] Considerable efforts have been devoted to the study of hydrolysis of cellulose by enzymes, acids, and supercritical water. Recently, acid-catalyzed hydrolysis has attracted increasing attention. To overcome resistance to degradation through breaking hydrogen bonds and b-1,4glycosidic bonds, ionic liquids have been employed to form homogeneous solutions of cellulose prior to hydrolysis. Although the homogeneous hydrolysis can be carried out under mild conditions with a high glucose yield, the workup for separation of sugars, dehydrated products, and unreacted cellulose from the ionic liquid is normally difficult. 4c, 5] Hydrolysis of cellulose in diluted acids has been practiced for a long time. However, acid-waste generation and corrosion hazards are significant drawbacks of this process. To move towards more environmentally sustainable approaches, Onda et al. demonstrated that sulfonated activated carbon can convert amorphous ball-milled cellulose into glucose with a yield of 41 %. Almost simultaneously, Hara et al. completely hydrolyzed cellulose to water soluble b-1,4-glucans at 100 8C using a more robust sulfonated activated carbon catalyst. Hydrolysis of cellobiose and cellulose catalyzed by layered niobium molybdate was achieved by Takagaki et al. , athough the yield of glucose from cellulose was low. Fukuoka et al. found that mesoporouscarbon-supported Ru catalysts were also able to catalyze the hydrolysis of cellulose into glucose. More recently, sulfonated silica/carbon cellulose hydrolysis catalysts were synthesized by Jacobs et al. , affording glucose in 50 % yield. Zhang et al. employed sulfonated carbon with mesoporous structure for hydrolysis of cellulose, giving a glucose yield of 75 %, which is the highest recorded yield on a solid acid. Considering the real biomass components and practical process for glucose production, two challenges remain for a catalytic system. Firstly, solid catalysts should be readily separated from the solid residues. Although cellulose can be converted almost completely in some cases, 11] lignin components can not be converted and humins are formed sometimes as solid residues. Secondly, to achieve a high yield of glucose, the reaction was usually conducted at low cellulose/liquid ratio (ca. 1:100). 8–11] However, concentration of the glucose solution, prior to the production of ethanol or other compounds, is energy-consuming. Thus effective treatment of high cellulose loadings is required. In view of the importance of the cellulose/liquid ratio, Jacobs et al. carried out hexitol production from concentrated cellulose with heteropoly acid and Ru/C. We designed and synthesized a magnetic solid acid catalyst for the hydrolysis of cellulose at high cellulose/liquid ratio (1:10 or 1:15; Scheme 1). Sulfonic acid-functionalized mesopo-

Hydrolysis of Cellulose into Glucose by Magnetic Solid Acid

Herein we reported a promising method for the production of aromatics from pyrolytic lignin (PL). Compared to the lignins derived from pulping process, the PLs obtained from bio-oil give more aromatics (40% in carbon yield) and do not generate effluvial gas containing sulfur. More importantly, phenols are the main products with selectivity over 90% at 600 °C without catalyst. In the presence of ZSM-5, the coke deposition was not obvious and the selectivity for aromatic hydrocarbons is more than 87%, indicating robustness of ZSM-5 for deoxygenating and high tolerance to PLs. Therefore we have demonstrated the catalytic pyrolysis of PLs is an alternative way to produce fuel additives and useful chemicals.

Li Deng

Papers

Catalytic conversion of biomass-derived carbohydrates into gamma-valerolactone without using an external H2 supply.

Hydrolysis of biomass by magnetic solid acid

Conversion of Levulinic Acid and Formic Acid into γ-Valerolactone over Heterogeneous Catalysts

Hydrolysis of Cellulose into Glucose by Magnetic Solid Acid

Aromatics Production via Catalytic Pyrolysis of Pyrolytic Lignins from Bio-Oil