Economic raw materials

In the 1950s, a group of coryneform bacteria which accumulate a large amount of L-glutamic acid in the culture medium were isolated (21). The use of mutant derivatives of these bacteria offered a new fermentation process for the production of many other kinds of amino acids (22). The amino acids which are produced by this method are mostiy of the T.-form, and the desired amino acid is singly accumulated. Therefore, it is very easy to isolate it from the culture broth. Rapid development of fermentative production and en2ymatic production have contributed to the lower costs of many protein amino acids and to their availabiUty in many fields as economical raw materials. 

LCI, where the system is quantified in a strict format of linked processes. Each process is described in terms of the physical inputs and outputs, both economic (raw materials, materials, products) and environmental (extractions from and emissions to the environment). Out of the total, an ecological profile is compiled listing and adding up all extractions and emissions of the system. An important methodological issue is allocation how to deal with multi-output processes This issue is especially important when dealing with waste management processes and will be dealt with below. 

Sintered spinel clinker has been developed as a more economical raw material than fused spinel, which it replaces in many applications. A1203, MgO and a selected binder (organic polymer or inorganic) are pulverised and mixed in a tube mill. After forming and drying, the mixture is sintered at temperatures above 1600°C in a rotary kiln until fully dense. 

Economics Raw material and utility requirements per metric ton of product ... 

In a realistic synthesis problem, the default constraint for compounds is that of excluded reactants, since most compounds in the database would not be available as economical raw materials. 

Petroleum chemicals fulfill two functions. They provide alternative and more economic routes to existing chemicals already made from other raw materials, and they lead to new industrial chemicals. The reactions of and outlets for chemicals more economically synthesized from petroleum have already been worked out, although perhaps not completely, in connection with the older routes. Those countries not favored with petroleum as an economic raw material have had to make use of alternative sources for these chemicals. In surveying the literature, it is, therefore, necessary to take account of the history of those petroleum chemicals which have been made from alternative sources. The reactions of methane are the same whether it is obtained from natural gas or as a by-product of the hydrogenation of coal or as a fraction in the liquefaction of coke oven gas depending on the source, the economics may be quite different. 

Economics Raw materials and utilities, per metric ton of pelletized polymer ... 

In the past 30 years, the ready availability and low cost of petroleum and natural gas, plus the Ingenuity of petroleum chemists and engineers, have made this the most convenient and economical raw material for synthesis of plastics, to the point where we have abandoned many of the older processes, or at least allowed them to remain relatively minor in importance ( ). 

Ethanol, commonly called simply alcohol, can be produced from virtually any plant by fermentation. The most economical raw materials are sugar cane (Brazil), com (US), wheat, potato and sugar beet (Europe). 

The nnmber of chemically conceivable amphoteric snrfactant strnctures is limited in practice to the derivatives of easily accessible and, therefore, economical raw materials. Relative to the amphoteric snrfactants with the combination of cationic nitrogen atom and carboxyl gronps, the so-called sulfo betaines with the sulfonate group, and also the phosphato betaines with the phosphate group as anionic component, play only a subordinate role. 

The enzymes, the principal biocatalysts of the living matter, are present in the organisms in most cases either bound to the cell membrane or included in the cytoplasmatic network. In order to reproduce in vitro some cell metabolic processess as close to reality as possible a wide variety of enz3mies, vitamins, hormones, nucleic acids and organite were immobilized on different natural and synthetic polymers 1" Subsequently, the immobilized enzymes were widely applied industrially in continuous biosyntheses with high yields and economizing raw materials " ... 

Raw materials are a critical issue in any process, and were particularly so in the Phosphate Fibers Project since safety was a critical issue. High-purity economical raw materials were readily available at locations where plants had been planned. Lime was likely to be the most tricky to handle, but this is true in most processes where lime is used. It is unlikely that any special problems should have arisen with the phosphate fibers. 

PP has proved to be a highly economical raw material, with the lowest energy content of all synthetic fibers, and a very favorable environmental position. POs are gradually taking their place as major manmade fibers in the international textile industry. 

Members of the LABS family of surfactants exhibit several characteristics that explain their predominance in many surfactant applications. They not only show outstanding surfactant properties in general but are also derived from raw materials that are relatively easy to obtain and less expensive than those from which the other main types of surfactant are prepared. The main source of the alkylbenzene sulfonates is the petroleum industry, and it will probably remain the most economical raw material for these materials for some time to come. 

---