SOLVENT USE IN VARIOUS INDUSTRIES

Attempts to reduce solvent use in the production of various materials require background information on the current inventory, the reasons for selecting certain solvents, the effect of various solvents on the properties of final products, future trends and the possibilities for solvent replacement. 

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Fermentation An anaerobic bioprocess. An enzymatic transformation of organic substrates, especially carbohydrates, generally accompanied by the evolution of gas as a byproduct. Fermentation is used in various industrial processes for the manufacture of products (e.g., alcohols, organic acids, solvents, and cheese) by the addition of yeasts, moulds, and bacteria. 

Many very hazardous solvents, such as benzene and carbon tetrachloride, were widely used until the 1970s. The situation was very similar for the use of pesticides. Among the toxic pesticides that were still in wide use 20 years ago were chlorophenols, DDT, lindane, and arsenic salts, all of which are classified as human carcinogens as well as being acutely toxic. Fortunately, use of these kinds of very toxic chemicals is now limited in the industrialized world. However, because the number of chemicals used in various industries continues to increase, the risks of long-term health hazards due to long-term exposure to low concentrations of chemicals continues to be a problem in the workplace. 

Polypropylene materials (PP), because of their electric properties (such as surface resistivity Ps, volume resistivity pv, dielectric loss factor tg8, permittivity e), mechanical properties and resistance to noxious agents (resistance to acids, bases, salts and organic solvents) are used in various industries. Polypropylene materials characterise, also, with the lowest specific density among widely used polymers. Those properties predispose polypropylene to be used as a substrate for composite protective screens shielding people and electric or electronic devices against noxious activity of electromagnetic (EM) fields. Composite shields... 

Again, many of the solvents discussed in this chapter are valuable intermediates for the preparation of various chemical products. Some of the solvents also find use in various industrial processes and applications. This chapter discusses the naming nomenclature for the nitrogen-type solvents, their physical properties, the various industrial uses, possible environmental concerns, and the safe handling of the solvents. 

The reaction depends on various factors including solvent, initial pressure, catalyst precursor and the N-protecting group. Due to the high stability of (S,S)-3-Pt-FerroPHOS towards air, it may be used in an industrial process. 

The Carver-Greenfield process (C-G process) is a patented drying and solvent extraction process designed to separate oil-soluble contaminants from liquid, solid, or slurry wastes. The process has been used extensively over the last 30 years to dry and extract compounds from a variety of wet, oily solids in various industries. C-G process units may consist of modular designs or custom made for large-capacity operations. 

Along with methods to evaluate different pharmaceutical processes and unit operations, several methods have also been developed to evaluate commonly used solvents in the pharmaceutical industry. Solvents still account for a majority of the mass utilization in any pharmaceutical process. Therefore, various methods have been developed which focus on measuring the greenness of solvents, locating possible alternatives and reducing the overall amount of solvent used in any given process. Some of these methods use a combination of physical property data, LCA... 

On the other hand, pressure is applied in reverse osmosis to drive the solvent (water) out of the high-concentration side into the low-concentration side this facilitates de-watering insoluble species for their removal. This process produces high-quality water and concentrated refuse. It separates and removes dissolved solids, organics, pyrogens, colloidal matter, viruses, and bacteria from water in the particle range 10 4—10—2 pm. Reverse osmosis can remove up to 95%-99% of the total dissolved solids (TDS) and 99% of all bacteria. It is used for the ob-tention of drinking water from seawater and for the production of ultra pure water in various industries. 

A low foaming emulsifier for organic solvents, can also be used as an emulsifier for paraffin oils in industrial lubricants. Its balanced solubility properties make it useful in various systems and in some instances can be used as the primary emulsifier. 

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