Petrochemical sources, alternative

One critical issue is the evaluation alternative. In the case of methanolysis, the alternatives are to make DMT and EG by depolymerization or secure materials from traditional petrochemical sources. For hydrolysis, the alternatives are TPA and EG by depolymerization or from traditional sources. For both technologies, the amount of copolymerizing isophthalate and/or 1,4-cyclohexane dimethanol is likely to be too little to justify the cost of recovery. For the various forms of glycolysis and the methanolysis/BHET hybrid, the alternative is the BHET and BHET-like materials made by the combination of a terephthalate and isophthalate plus EG and various glycols. Market prices exist for TPA and EG. BHET is not an item of commerce, and so the value must be imputed from the market price for TPA (the modern terephthaloyl) and EG, plus a conversion cost. 

In many cases, food crops are exploited to provide abundant sources of carbohydrates and oils that are then diverted to industrial uses, for example corn, potatoes and wheat for starch, and oilseed rape and sunflower for oil. In other cases, nonedible crops are commercialised primarily for specific industrial or medicinal use, where examples include linseed, castor bean and rubber palm. Where plants are commercialised for industrial uses, unless products command a very high value, candidate plants must be capable of producing large quantities of the metabolites of interest. In the case of oils for specific uses, this means plants must be enriched in specific fatty acids. This arises from the fact that plant-derived chemicals in many cases compete with petrochemical-derived alternatives and this requires that costs of extraction and refining are kept as low as possible in order to remain commercially competitive. 

Ultimately non-petrochemical sources of raw materials will become more economical, and synthesis of plastics will turn to these alternate sources, some to produce our present plastics, others to produce new types of plastics. Coal, forestry, and agriculture offer a great variety of interesting opportunities, whenever the economics appear appropriate (5). 

TTntil the recent years of renewed concern for alternative fuel oil and petrochemical sources, interest in the mineral shales which contain the earth s most abundant organic matter, kerogen, has been sporadic. Both in the United States and throughout the world there are vast shale reserves, but the technology to exploit them and extract the oil from... 

Isoprene is a commodity chemical used in the production of synthetic rubber, adhesives, and specialty elastomers. Manufacturing of isoprene is currently based on petrochemical sources, but significant progress has been made to develop an alternative fermentation-based isoprene source (Whited et al., 2010). 

Alternative feedstocks for petrochemicals have been the subject of much research and study over the past several decades, but have not yet become economically attractive. Chemical producers are expected to continue to use fossil fuels for energy and feedstock needs for the next 75 years. The most promising sources which have received the most attention include coal, tar sands, oil shale, and biomass. Near-term advances ia coal-gasification technology offer the greatest potential to replace oil- and gas-based feedstocks ia selected appHcations (10) (see Feedstocks, coal chemicals). 

Because oil and gas ate not renewable resources, at some point in time alternative feedstocks will become attractive however, this point appears to be fat in the future. Of the alternatives, only biomass is a renewable resource (see Fuels frombiomass). The only chemical produced from biomass in commercial quantities at the present time is ethanol by fermentation. The cost of ethanol from biomass is not yet competitive with synthetically produced ethanol from ethylene. Ethanol (qv) can be converted into a number of petrochemical derivatives and could become a significant source. 

The search for alternative ways to produce monomers and chemicals from sources other than oil, such as coal, has revived working using Fisher Tropseh technology, which produces in addition to fuels, light olefins, sulfur, phenols, etc. These could he used as feedstocks for petrochemicals as indicated in Chapter 4. 

Use of renewable feedstocks is most likely where they can compete economically with petrochemically derived materials. This already happens in many areas, and it is sometimes forgotten that even in a world that seems to be dominated by chemicals and materials from fossil carbon and other non-renewable sources, industry already uses annually 19.8 MT of vegetable oils, 22.5 MT starch, 28.4 MT of plant fibres and 42.5 MT of wood pulp. These all compete on price and performance with synthetic alternatives. 

The preparation of intermediate petrochemical streams requires different processing alternatives depending on the feedstock quality. In our classification of petrochemical feedstocks we closely follow that of Gary and Handwerk (1994) consisting of aromatics, olefins, and parafftn/cyclo-parafftn compounds. The classification of petrochemical feedstocks into these clusters helps to identify the different sources in the refinery that provide suitable feedstock and, therefore, to better recognize areas of synergy between the refinery and petrochemical systems. 

The paper provides an overall cooling system model called Unimod. The model is applied to present and future cooling system requirements, and eliminates plant trials of treatment chemicals. At a midwest refinery petrochemical plant, oil leaks, the use of four alternating water sources, and entrained solids were causing heat transfer losses and unscheduled shutdowns. In less than an hour, the model identified the best of the available water sources and blends, and recommended a treatment program for use before each water change. This enabled the refinery to increase heat transfer by 20%, eliminate unscheduled shutdowns, and with treatment, use the plant wastewater safely for all cooling water makeup. 

APILIT2 is a bibliographic database containing citations for nonpatent literature pertaining to the petroleum and petrochemical industries, including information on alternate energy sources and environmental effects. It is produced by the American Institute of Petroleum and covers 1964 to date. 

The technology is rapidly approaching a state of development that can provide reliable commercial design data. Just as rapidly, the critical nature of the world energy outlook is becoming more definitized, making it obvious that any reasonable alternatives to crude oil as a source of fuel and petrochemicals must be evaluated for commercial potential as expeditiuosly as possible. 

In nature, the availability of starch is just second to cellulose. The most important industrial sources of starch are corn, wheat, potato, tapioca and rice. In the last decade, there has been a significant reduction in the price of corn and potato starch, both in Europe and the USA. The lower price and greater availability of starch associated with its very favourable environmental profile aroused a renewed interest in development of starch-based polymers as an alternative to polymers based on petrochemicals. 

Since the oil shortages of the 1970s, there has been a sustained search for materials to replace the petroleum-based resins used as durable adhesives for exterior wood products. Such alternatives are considered important, because supplies of petrochemicals for use in the wood industry could again become undependable. Ideally, the source of material for an adhesive would be readily available, possibly from materials already found near or used by wood processing plants, for example, agricultural or wood-based renewable resources. The purpose of this investigation was to explore the use of carbohydrates as constituents in water-resistant adhesives. 

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