Liquid hydrocarbon from biomass

Recently, extensive efforts have been made to synthesize liquid hydrocarbons from biomass feedstocks. In 2004, Dumesic and co-workers reported that a clean stream of alkanes could be produced by aqueous phase reforming of sorbitol over a bifunctional catalyst. The sugar is repeatedly dehydrated using a solid acid catalyst and then hydrogenated using a precious metal catalyst such... 

Hydropyrolysis process gives the higher degree of mixture conversion and higher yield of light liquids as compare to pyrolysis in an inert atmosphere. Observed in some cases non-additive effects indicate that the interaction between wood and plastic derived products takes place during mixture thermal treatment. The more pronounced synergistic effects were detected for hydropyrolysis process. Iron catalysts promote the formation of liquid hydrocarbons from biomass/plastic mixtures and influence on their coit sition. 

Consecutively, the heavy paraffins are cracked into lighter hydrocarbon fractions by hydro-cracking. For example, for the Shell Middle Distillate Synthesis (SMDS) process, the liquid product stream is composed of 60% gasoil (diesel), 25% kerosene and 15% naphtha. The gaseous product mainly consists of LPG (a mixture of propane and butane) (Eilers et al., 1990). Figure 7.3 shows a simplified diagram comprising all process steps to produce synthetic hydrocarbons from biomass, natural gas and coal. 

Liquid phase catalytic processing is a promising biorefinery process that produces functionalized hydrocarbons from biomass-derived intermediates (e.g., intermediate hydroxymethylfurfural or HMF). Renewable furan derivatives can be used as substitute building blocks for fossil fuels, plastics, and fine chemicals, ° or to develop biofuels based on C5 and C6 carbohydrates (sugars, hemicellulose, cellulose). Currently, Avantium Chemicals in the Netherlands is developing chemical catalytic routes to generate furanics for renewable polymers, bulk and specialty chemicals, and biofuels. ... 

Elliott, D.C., Wang, H., French, R., Deutch, S., lisa, K., 2014. Hydrocarbon liquid production from biomass via hot-vapor filtered fast pyrolysis and catalytic hydroprocessing of the biooil. Energy Fuels 28, 5909—5917. 

Both the production of hydrogen from coal and the production of oil from unconventional resources (oil sands, oil shale, CTL, GTL) result in high C02 emissions and substantially increase the carbon footprint of fuel supply, unless the C02 is captured and stored. While the capture of C02 at a central point source is equally possible for unconventionals and centralised hydrogen production, in the case of hydrogen, a C02-free fuel results, unlike in the case of liquid hydrocarbon fuels. This is all the more important, as around 80% of the WTW C02 emissions result from the fuel use in the vehicles. If CCS were applied to hydrogen production from biomass, a net C02 removal from the atmosphere would even be achievable. 

Elliot, D.C., Baker, E.G., Hydrotreating biomass liquids to produce hydrocarbon fuels, In Klass, D.L. (ed.), 1987, Energy from Biomass and Waste, publ. IGT, Chicago, p. 765. 

Elliott, D.C., Schiefelbein, G.F., Liquid hydrocarbon fuels from biomass, Am. Chem. Soc., Div. Fuel. Chem., 1989, 34, 1160. 

The role of biocomponents in traffic fuel is increasing. The European Union Directive [1] on the promotion of the use of biofuels for transport purposes states that by the end 2005 traffic fuels should have contained 2% of components produced from renewables. The figure rises to 5.75% by the end of 2010 and up to 20% by the end of 2020. This directive defines biofuel as a liquid or gaseous fuel for transport produced from biomass, biodiesel as a methyl ester produced from vegetable or animal oil, of diesel quality, to be used as biofuel and synthetic biofuel as synthetic hydrocarbons or mixtures of synthetic hydrocarbons, which have been produced from biomass. The European Commission also encourages member states to lower tax rates on pure and/or blended biofuels, to the offset cost premium over petroleum-based fuels [1, 2]. 

For many applications, hydrogen is the most convenient fuel, but it is not a primary fuel, so that it has to be produced from different sources water, fossil fuels (natural gas, hydrocarbons, etc.), biomass resources and so on. Moreover, the clean production of hydrogen (including the limitation of carbon dioxide production) and the difficulties with its storage and large-scale distribution are still strong limitations for the development of such techniques [2, 3]. In this context, other fuels, particularly those, like alcohols, which are liquid at ambient temperature and pressure, are more convenient due to the ease of their handling and distribution. 

See, for instance J. E. Sanderson, D. L. Wise and D. G. Augenstein, "Liquid Hydrocarbon Fuels from Aquatic Biomass , Paper No. 27 presented at the Second Annual Fuels from Biomass Symposium, Rensselaer Polytechnic Institute, Troy, New York (June 20-22, 1978). 

The FTS converts synthesis gas into mostly liquid hydrocarbons [12-15]. Depending on the origin of the synthesis gas, the overall process from carbon feedstock to liquid product is called gas-to-liquids (GTL), coal to liquids (CTL), or biomass to liquids (BTL). The product spectrum, however, is broader than liquid hydrocarbons alone and can include methane and alkanes, C H2 +2 (with n from 1 — 100), alkenes or olefins (C H2 n > 2), and to a lesser extent, oxygenated products such as alcohols. Hence the FTS offers the opportunity to convert gas, coal, or biomass-derived syngas into transportation fuels, such as gasoline, jet fuel, and diesel oil, and chemicals, such as olefins, naphtha, and waxes. The reactions need a catalyst, which in commercial applications is either based on cobalt or iron. 

It would seem that a more practical approach to the upgrading of pyrolytic liquids from biomass is to utilize what is already on hand, namely, the oxygenated product liquids. Instead of conversion to hydrocarbons, which usually requires severe reaction conditions, why not convert the liquids by simple chemistry to other liquids that are suitable for use as motor fuels or additives Although not directly related to pyrolysis, this approach has been pursued in... 

The projections of liquid hydrocarbon yields from the Brazilian tree C. multijuga in plantation settings and the yields of biocrude from E. lathyris and E. tirucalli have been quite optimistic. However, the main difficulties with the concept of natural hydrocarbon production from biomass are that most of the species that have been tested exhibit low liquid yields compared to the mass of biomass that must be harvested, and the naturally produced liquids are complex mixtures and not pure hydrocarbons (or glycerides). Moreover, the relationship between the minimum hydrocarbon content of dry biomass and biomass yield required to sustain a terpene yield of 25 bbl/ha-year tends to preclude sustainable production at this level. This is perhaps best illustrated by Fig. 10.2. The curve is constructed by assuming the density of terpene hydrocarbons is in the range 0.1347 t/bbl, which is the literature value for... 

Annee J.H.J, Ruytei H.P. (1986) Process for producing hydrocarbon-containing liquids from biomass. European Patent 0204354, to Shell Ineinationale Research Maatsebappij B.V. 

With ever increasing requirements for clean transportation fuels and liquid hydrocarbon supplies, there is an opportunity to produce significant quantities of synthetic ultra-clean fuels that are essentially sulfur-free. These synthetic fuels can be produced from natural gas, coal, petroleum coke, biomass, and other non-traditional hydrocarbon sources. Most of these products are fungible and compatible with current products and distribution infrastructure and can be produced at costs competitive with conventional crude oil-derived products under certain market conditions. 

Synthetic liquid fuels Renewably produced hydrogen again provides the dominant transport fuel. In this case, however, it is packaged in the form of a synthetic liquid hydrocarbon, such as methanol, to overcome the difficulties of hydrogen storage and distribution. The carbon for fuel synthesis comes from biomass and from the flue gases of carbon-intensive industries. 

Oxidation reactions play a crucial role in the chemical industry, where >90% of the feedstocks derive from hydrocarbons - the most reduced organic chemicals on the planet. Sustainability concerns are demanding a greater shift toward biomass-derived feedstocks however, oxidation methods will continue to play a major role. For example, even as this book goes to press (March 2016), BASF and Avantium have just announced plans to pursue a joint venture for the production of 2,5-furandicarboxylic acid (FDCA), an important polymer-building block derived from biomass. The proposed 50000 metric tons per year plant will undoubtedly incorporate liquid phase aerobic oxidation chemistry similar to that described in Chapter 19 of this volume. 

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