Hydrocarbon from biomass

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. 

Barrefors G, Petersson G. 1995. Assessment by gas chromatography and gas chromatography-mass spectrometry of volatile hydrocarbons from biomass burning. J Chromatogr 710 71-77. 

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. 

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. ... 

Jahangiri H, Bennett J, Mahjoubi P, Wilson K, Gu S A review of advanced catalyst development for Fischer-Tropsch synthesis of hydrocarbons from biomass derived syn-gas, Catal Sci Technol 4 8) 2210-2229, 2014. http //dx.doi.org/10.1039/c4cy00327f. 

Wang, C., et al., 2008. Production of Ught aromatic hydrocarbons from biomass by catalytic pyrolysis. Chinese Journal of Catalysis 29 (9), 907—912. 

Speight, J.G., 2011a. Chapter 7-Hydrocarbons from biomass. In Speight, J.G. (Ed.), Handbook of Industrial Hydrocarbon Processes. Gulf Professional Publishing, Boston, pp. 241—279. 

An alternative method of produciag hydrocarbon fuels from biomass uses oils that are produced ia certaia plant seeds, such as rape seed, sunflowers, or oil palms, or from aquatic plants (see Soybeans and other oilseeds). Certain aquatic plants produce oils that can be extracted and upgraded to produce diesel fuel. The primary processiag requirement is to isolate the hydrocarbon portion of the carbon chain that closely matches diesel fuel and modify its combustion characteristics by chemical processiag. 

Whilst the basic process for generation and conversion of syngas is well established, production from biomass poses several challenges. These centre on the co-production of tars and hydrocarbons during the biomass gasification process, which is typically carried out at 800 °C. Recent advances in the production of more robust catalysts and catalytic membrane reactors should overcome many of these challenges. 

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. 

This chapter surveys different process options to convert terpenes, plant oils, carbohydrates and lignocellulosic materials into valuable chemicals and polymers. Three different strategies of conversion processes integrated in a biorefinery scheme are proposed from biomass to bioproducts via degraded molecules , from platform molecules to bioproducts , and from biomass to bioproducts via new synthesis routes . Selected examples representative of the three options are given. Attention is focused on conversions based on one-pot reactions involving one or several catalytic steps that could be used to replace conventional synthetic routes developed for hydrocarbons. 

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 soybean-based biodiesel at this concentration, the estimated emission impacts for percent change in emissions of NO,, particular matter (PM), HC, and CO were +20%, -10.1%, -21.1%, and -11.0%, respectively (EPA, 2002). The use of blends of biodiesel and diesel oil are preferred in engines in order to avoid some problems related to the decrease of power and torque, and to the increase of NO, emissions (a contributing factor in the localized formation of smog and ozone) that occurs with an increase in the content of pure biodiesel in a blend. Emissions of all pollutants except NO appear to decrease when biodiesel is used. The use of biodiesel in a conventional diesel engine dramatically reduces the emissions of unbumed hydrocarbons, carbon dioxide, carbon monoxide, sulfates, polycyclic aromatic hydrocarbons, nitrated polycyclic aromatic hydrocarbons, ozone-forming hydrocarbons, and particulate matter. The net contribution of carbon dioxide from biomass combustion is small. 

The catalytic aqueous phase reforming might prove useful for the generation of hydrogen-rich gas from carbohydrates extracted from renewable biomass and biomass waste streams. The biomass-derived hydrocarbons are suitable to hydrogen generation from biomass, as well as for the reforming. 

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. 

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