Zeolite biomass conversion

Milne TA, Evans RJ, Nagle N. 1990. Catalytic conversion of microalgae and vegetable oils to premium gasoline, with shape-selective zeolites. Biomass 21 219-232. 

Selective isomerization of glucose to fructose in aqueous medium Sn-p zeolite Fructose is easier to transform in suitable platform molecules than the abundant glucose. Hence, to find selective catalysts for this transformation is a critical key in the lignocellulosic biomass conversion [74]... 

Taaming E, Osmundsen CM, Yang X, Voss B, Andersen SI, Christensen CH (2011) Zeolite-catalyzed biomass conversion to fuels and chemicals. Energy Environ Sci 4(3) 793-804... 

Jungho J., Geoffrey A. T, Andrew J. E, Karl D. H., Scott M. A., Raul F. L, George W. H. Investigation into the shape selectivity of zeolite catalysts for biomass conversion. Journal of Catalysis 279, 257-268 (2011). 

This chapter explored the current state of the use of zeolites in biomass conversion strategies. From this, it can be concluded that zeolites, in an extension to their success in petrochemistry, can also play a pivotal role in the conversion of biomass. The success of zeolites in petrochemistry is closely linked to their strong Bronsted acidity in a crystalline matrix with porosity of molecular dimensions which could be one by one easily modified. The examples in this chapter showed that these properties are also very decisive in biomass transformations. 

Dijkmans J, Dusselier M, Gabriels D, Houthoofd K, Magusin PCMM, Huang S, et al. Cooperative catalysis for multistep biomass conversion with Sn/Al beta zeolite. ACS Catal 2015 5 928 40. 

Mentzel UV, Hohn MS. Utilization of biomass conversion of model compounds to hydrocarbons over zeolite H-ZSM-5. Appl Catal A 2011 396 59-67. 

The low H/C-ratio of FCC feed derived from liquefied biomass led to low conversion and poor gasoline selectivity. Addition of alumina to the matrix resulted in a catalyst more active for heavy oil cracking but with a poor selectivity. Alumina-montmorillonite catalysts showed activities for heavy oil cracking comparable to that of a conventional, zeolite based, cracking catalyst. Effects of matrix composition and zeolite type on the heavy oil cracking performance are discussed. 

As biomaterials are structurally and chemically complex, biomass thermochemical conversion processes (1,2) produce complex fractions including a liquid fraction which, dep>ending on the process, can be obtained in large (liquefaction, pyrolysis) or small yields (gasification). These liquids have found little utility because of their large contents in oxygen which implies low heat values, instability and corrosive prop>erties. Two routes have been tested (3,4) in order to produce hydrocarbons from these liquids. The first one involves hydrotreatment with either H2 or H2 + CO over classical hydrotreatment catalysts. The second route is the simultaneous dehydration and decarboxylation over HZSM-5 zeolite catalyst in the absence of any reducing gas. 

The goal of the molecular-beam, mass-spectrometry (MBMS) studies of biomass pyrolysis product conversion over zeolite catalysts is to provide rapid characterization, in real time, of the fate of the complex reactants as a function of reaction parameters. This technique allows the qualitative observation of transient, reactive and high molecular weight reactants and products that might otherwise escape detection by conventional collection and analysis methods. The goal is to optimize gasoline yields from biomass, at this small scale, by evaluating a typical Mobil HZSM-5 zeolite in its ability... 

Previous Work in Zeolite Conversion of Biomass Vapors. Applications of zeolites for the conversion of oxygenates in general and biomass pyrolysis products in particular has been previously reviewed (1,2). Over the last decade, Mobil researchers (e.g., 3-5) and others (6-17) have examined a variety of oxygenated compounds over HZSM-5 catalysts of various origins. Several investigators have converted wood pyrolysis products (10-14). 

Recent work at SERI has focussed on the study of direct wood-vapor conversion without an oil condensation step (J ). The MBMS experimental system (18-21) has been used to show that the biomass pyrolysis vapors were reactive on the HZSM-5 zeolite catalyst. The complete destruction of all primary products was observed, and a method of monitoring deactivation of the catalyst was demonstrated. Specifically, the carbohydrates were converted beyond the furans to light olefins and aromatics and the lignin products were also completely destroyed with the same classes of gaseous products. However, the coking tendency of each class of starting material was not quantified at that time. 

Methods for the conversion of biomass into a slate of product, also comprising chemicals like p-xylene, are those promoted by US-based companies Anellotech and Virent. In Anellotech s Biomass to Aromatics process, biomass such as corn, sugar beet and so on is dried and milled, and then injected into a fluidized bed in the presence of a cheap zeolite, based on ZSM-5. The process takes place at high temperatures (600 °C) at a short period of time. Coking initially was considered as a drawback in this process. Annellotech claims to be able to produce 190 L product out of 1 ton biomass (www.anellotech.com, accessed 22 June 2013). So far the process has been performed on a small scale only and scale-up needs to be realized. 

Multifunctional Zeolites Efficient, multifunctional zeolite-based catalysts allowing one-step complex reactions are of great interest in the field of fine chemicals and organic industrial synthesis [58]. Recendy, catalysts based on zeolites are relevant in emerging areas of interest such as the catalytic conversion of biomass to fuels and chemicals (see Section 8.2.1.3 for illustrative examples). This field needs to develop specific multifunctional catalysts having the correct polarity (adsorption properties) and reactant accessibility (porosity), which are efficient in water or biphasic operation with reactants and products of different polarities and sizes. Hence, great opportunities for zeolites and related materials are offered in this new field [59-61]. 

Huang WW, Gong FY, Fan MH, Zhai Q, Hong CG, Li QX (2012) Production of light olefins by catalytic conversion of lignocellulosic biomass with HZSM-5 zeolite impregnated with 6 wt.% lanthanum. Bioresour Technol 121 248... 

Reductive processes utilizing carboxyhc acid derivatives also provide routes to ketenes. These include the conversion of biomass to useful oils with catalysis by metal oxides or zeolites, which imphcate the possible role of ketene formation in the conversion of esters, as su ested by the necessity of a-hydrogens in the ester substrates (Eqn (4.16)). An outline of the process of dehydration of the acid to form the ketene on the metal surface is shown in Figure 4.7. 

Conversion of Biomass to Chemicals The Catalytic Role of Zeolites... 

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