Feedstocks for the chemical industry

At the Coal Research Establishment of the National Coal Board, methods for the liquefaction of coals to produce transport fuels, feedstocks for the chemical industry and high purity carbons suitable for electrode manufacture are being developed. 

Beyond the transportation sector, biomass is also a promising feedstock for the chemical industry. This industry accounts for 5-10% of today s oil and gas consumption. It may require an even larger fraction in the future as the demand for chemicals has outpaced that for energy in the last few decades. Recently, the chemical industry has indeed showed a significant interest in converting agricultural feedstock into chemical intermediates such lactic acid or propene-l,3-diol. 

The current utilization of carbohydrates as a feedstock for the chemical industry—be it for bulk, commodity, intermediate, fine, or high-value-added speciality chemicals—is modest when considering their ready availability at low cost and the huge as yet unexploited potential. The examples currently realized on an industrial scale are outlined briefly. 

Beyond DMC and its utilization as methylating agent or as poly condensation building block, CO2 can be used as feedstock in a number of reactions that are highlighted in Figure 10.7. Most of these reactions need further research before CO2 can be utilized as a mass feedstock for the chemical industry. 

There are many ways in which biomass can be envisaged to become an increasingly important feedstock for the chemical industry, and this has already been the topic of numerous studies. The most comprehensive study was published recently by Corma et al ° and it contains a very detailed review of possible routes to produce chemicals from biomass. 

Ethanol. Ethanol is the most important chemical produced by fermentation, and it has the potential to become a major feedstock for the chemical industry since many other large-scale chemicals can be produced from ethanol. In fact, ethanol can in many respects be considered a renewable alternative to ethylene, which is the largest volume carbon-containing chemical produced from fossil resources today. Via catalytic dehydration, ethanol can easily be converted into ethylene and diethyl ether, both of which are well-known acid catalyzed processes. Almost all available... 

Ever since Nehemiah demonstrated, albeit with divine assistance, that naphtha would burn,1 man has increasingly relied on oil and oil based products for fuel as well as for feedstocks for the chemical industry. However, it was not until the invention of the internal combustion engine in the latter part of the 19th century that total exploitation of this resource became a reality. 

The present utilization of carbohydrates as a feedstock for the chemical industry is modest, when considering their ready availability, low cost and huge potential [92], The bulk of the annually renewable carbohydrate biomass consists of polysaccharides, but their non-food utilization is still modest. The low-molecular-weight carbohydrates, that is, the constituent units of these polysaccharides, are potential raw materials for several commodity chemicals in fact, glucose (available from cornstarch, bagasse, molasses, wood), fructose (inulin), xylose (hemicelluloses) or the disaccharide sucrose (world production 140 Mtons year-1) are inexpensive and available on a scale of several ten thousands. 

In 2008, increases in the price of oil and the recognition of a need to reduce the impact of the chemical and energy industries on climate change, notably by reducing the emission of C02, directed interest towards the use of renewable sources of energy and alternative feedstocks for the chemical industry. This strategy... 

Many of the feedstocks for the chemical industry, especially aromatic hydrocarbons, were originally obtained as by-products from the carbonization of coal. (1,2) However, nowadays, most of these chemical feedstocks are derived from petroleum. Nevertheless, it is probable that, within the next few decades, the shortage of world reserves of petroleum will mean that BTX will once again have to be produced from coal, as will ethylene. It is, therefore, appropriate to examine ways in which these materials can be produced from coal the present investigation was designed to study the formation of BTX and ethylene by the thermal cracking of coal-derived materials from the NCB coal liquefaction/hydrogenation processes. (3)... 

Alkanes, which are the principal components of natural gas and crude oil, are still the preferred energy source of our society. In regard to the prime importance of alkanes as feedstock for the chemical industry, it appears a waste of resources simply to burn these precious raw materials. Unfortunately, attempts to transform alkanes into more valuable products are hampered by their low reactivity, as best illustrated by the use of alkanes as inert solvents. For example, the cracking process requires temperatures of about 1000 °C in order to convert long-chain alkanes into short-chain alkanes. Controlled conversion of hydrocarbons is difficult to achieve and limited to partial oxidations, such as the conversion of butane into acetic acid. It is obvious that processes that would enable efficient functionalization to occur at low temperature would have enormous potential application. Achievements towards this goal will almost certainly rely on the use of catalysts, which will have to activate the stable C-H bond (375-440 kf mol-1) in order to induce its scission. 

The use of organometallic rhenium complexes has found a very broad scope as oxidation catalysts as described in the previous section, making MTO the catalyst of choice for many oxidation reactions of olefins. Interestingly, MTO and related rhenium compounds have also found application in the reverse reaction, the deoxygenation of alcohols and diols. Especially in recent years, this reaction has attracted much attention due to the increased interest in the use of biomass as feedstock for the chemical industry. This section provides an overview of the use of rhenium-based catalysts in the deoxygenation reaction of renewables. 

In the following sections, current and potential future means by which plants can be exploited to produce feedstocks for the chemical industry are reviewed by key plant metabolite sectors ... 

Light petroleum and ligroin 20-120°C C5-C7 compounds large amounts are heated to crack them to small alkenes, a major feedstock for the chemical industry... 

If methanol should ever enter into these new applications, it will also be available as feedstock for the chemical industry in practically any amount and at rather low cost. For a detailed analysis of the future methanol market, the World Methanol Study by SRI gives some excellent information (18J. 

Fossil fuels are extremely versatile energy sources. They serve a wide diversity of purposes, including transportation, heating, electricity, industrial applications and feedstock for the chemical industry. Crude oil in particular can be separated and processed into a wide range of usefiil products. Its lightest fractions - consisting mainly of propane and butane - are in the gaseous state at ambient pressure and temperature, but may be liquefied at relatively low pressures. This liquefied petroleum gas (LPG) is suitable for a variety of applications as feedstock for the... 

Oxidation of saturated hydrocarbons, the main feedstocks for the chemical industry, is extremely important. With simple substrates such as cyclohexane or adaman-tane, selective oxidation can be achieved, typically by using hydrogen peroxide or peroxycarboxylic acids in combination with strong acids or transition metal... 

Isopropyl alcohol is extensively used in cosmetics, particularly for hair and skin lotions, and in pharmacy for preparations intended for external use. A further large area of use is the paint and printing ink industry. Isopropyl alcohol is added to fuels to prevent the icing up of the carburetor and increase the octane number. It is an important feedstock for the chemical industry, for example, in the production of acetone (particularly in the United States), esters, plasticizers, and ethers. Isopropyl alcohol is also important as a solvent (e.g., for recrystallization and extraction) and as a moistening agent for cellulose nitrate. It is furthermore used in the aerosol sector. 

Renewable Raw Materials New Feedstocks for the Chemical Industry, First Edition. 

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