Useful products

Unwanted byproducts usually cannot be converted back to useful products or raw materials. The reaction to unwanted byproducts creates both raw materials costs due to the raw materials which are wasted in their formation and environmental costs for their disposal. Thus maximum selectivity is wanted for the chosen reactor conversion. The objectives at this stage can be summarized as follows ... 

The most widely used product is TRO (TR for turbo-reactor) or JP8 (JP for Jet Propulsion), still designated by the NATO symbols F34 and F35. In the United States, the corresponding fuel is called Jet Al. The military sometimes still uses a more volatile jet fuel called TR4, JP4, Jet B, F45 or F40. The preceding terms correspond to slight variations and it would be superfluous to describe them here. 

The oil and gas industry produces much waste material, such as scrap metal, human waste, unspent chemicals, oily sludges and radiation. All of the incoming streams to a facility such as a production platform end up somewhere, and only few of the outgoing streams are useful product. It is one of the responsibilities of the engineer to try to limit the amount of incoming material which will finally become waste material. 

Waste disposal is an aspect of the production process which must be considered at FDP stage. This should cover all effluent streams other than the useful product including... 

Acetanilide (IV,45, Method 2, J scale boil reaction mixture for 15 minutes). Use product for preparations 24 and 25. 

Methylation of hydrocortisone/prednisolone ia positions C-4, C-7, C-12, and C-21 failed to give useful products. Methylation at C-16, ia contrast, led to 16a- and 16P-methyl-9a- uoroprednisolones which were exceptionally useful. Both series were prepared usiag 3a-acetoxy-5a-pregn-16-ene-ll,20-dione derived from desoxychoHc acid (80). A much shorter route was subsequentiy developed from... 

Acrylics. Acetone is converted via the intermediate acetone cyanohydrin to the monomer methyl methacrylate (MMA) [80-62-6]. The MMA is polymerized to poly(methyl methacrylate) (PMMA) to make the familiar clear acryUc sheet. PMMA is also used in mol ding and extmsion powders. Hydrolysis of acetone cyanohydrin gives methacrylic acid (MAA), a monomer which goes direcdy into acryUc latexes, carboxylated styrene—butadiene polymers, or ethylene—MAA ionomers. As part of the methacrylic stmcture, acetone is found in the following major end use products acryUc sheet mol ding resins, impact modifiers and processing aids, acryUc film, ABS and polyester resin modifiers, surface coatings, acryUc lacquers, emulsion polymers, petroleum chemicals, and various copolymers (see METHACRYLIC ACID AND DERIVATIVES METHACRYLIC POLYMERS). 

Another factor potentially affecting the market for halogenated fire retardants is the waste disposal of plastics (see Wastes, industrial). As landfiU availabihty declines or becomes less popular, two alternatives are incineration and recycling (qv). The nature of the combustion products from halogenated products requires carefiil constmction and maintenance of incinerators (qv) to avoid damage to the incinerator itself and a pubHc health problem from the exhaust. The ease of recycling used products also has a potential effect on fire retardants. 

Flame letaidancy can be impaited to plastics by incorporating elements such as bromine, chlorine, antimony, tin, molybdenum, phosphoms, aluminum, and magnesium, either duriag the manufacture or when the plastics are compounded iato some useful product. Phosphoms, bromine, and chlorine are usually iacorporated as some organic compound. The other inorganic flame retardants are discussed hereia. 

Catalytic methanation processes include (/) fixed or fluidized catalyst-bed reactors where temperature rise is controlled by heat exchange or by direct cooling using product gas recycle (2) through wall-cooled reactor where temperature is controlled by heat removal through the walls of catalyst-filled tubes (J) tube-wall reactors where a nickel—aluminum alloy is flame-sprayed and treated to form a Raney-nickel catalyst bonded to the reactor tube heat-exchange surface and (4) slurry or Hquid-phase (oil) methanation. 

The Fair Packaging and Labeling Act does not apply to products used in professional estabHshments. Specifically, this means that these products are not required to have an identity statement or a Hst of ingredients. This exception, however, is limited only to those products actually intended for professional use. Products sold by the professional estabHshments to their customers for personal use are considered retail products and must be fully labeled as such. 

The Fair Packaging and Labeling Act, which uses the same definitions for dmgs and cosmetics as the Food, Dmg and Cosmetic Act, only has jurisdiction over retail products sold to the consumer for use at home. This condition exempts free samples and professional use products not sold to a consumer for personal use. 

Several companies offer oils for heat-transfer service. Physical characteristics are summarized in Table 1. The oils discussed herein are widely used. Product brochures on the fluids are available from the manufacturers (3—12). 

Ethynylation. Base-catalyzed addition of acetylene to carbonyl compounds to form -yn-ols and -yn-glycols (see Acetylene-DERIVED chemicals) is a general and versatile reaction for the production of many commercially useful products. Finely divided KOH can be used in organic solvents or Hquid ammonia. The latter system is widely used for the production of pharmaceuticals and perfumes. The primary commercial appHcation of ethynylation is in the production of 2-butyne-l,4-diol from acetylene and formaldehyde using supported copper acetyHde as catalyst in an aqueous Hquid-fiHed system. 

Latex technology encompasses coUoidal and polymer chemistry ia the preparation, processing, and conversion of natural and synthetic latices into useful products. 

Section 15. General Products, Chemical Specialties and End-use Products (1 vol.)... 

Naturally Derived Materials. The following are descriptions of some of the most important naturally derived materials in use. Importance in this context is defined in terms of the total value of the materials, which range from expensive, low volume materials that have great aesthetic value to relatively inexpensive and widely used products. Eor some of the naturals, it is indicated whether they can be distilled to provide individual chemicals for use as such or as intermediates. Materials produced in this way from a given natural source are usually not interchangeable with those from other naturals or synthetics. In some cases this may be due to optical isomerism, which can have a significant effect on odor, but usually it is due to trace impurities. 

Estimated Emissions to the Environment. Phthalates maybe emitted to the environment during their incorporation into PVC and from the finished PVC article during its use or after its final disposal. However, because their purpose is to make PVC flexible and for it to remain so over long periods of time, plasticizers are of very low volatiUty relative to many other commonly used products, for example solvents. 

The expiration of Phillips basic PPS patent in 1984 ushered in a large interest from the industrial sector. Companies, based largely in Europe and Japan, began acquiring patents worldwide for both the synthesis of PPS and a wide variety of appHcations, including compounds, blends, alloys, fiber, film, advanced composite materials, as well as end use products. 

Amino resins are manufactured throughout the industrialized world to provide a wide variety of useful products. Adhesives (qv), representing the largest single market, are used to make plywood, chipboard, and sawdust board. Other types are used to make laminated wood beams, parquet flooring, and for furniture assembly (see Wood-BASED composites and laminates). 

Propylene oxide [75-56-9] (methyloxirane, 1,2-epoxypropane) is a significant organic chemical used primarily as a reaction intermediate for production of polyether polyols, propylene glycol, alkanolamines (qv), glycol ethers, and many other useful products (see Glycols). Propylene oxide was first prepared in 1861 by Oser and first polymerized by Levene and Walti in 1927 (1). Propylene oxide is manufactured by two basic processes the traditional chlorohydrin process (see Chlorohydrins) and the hydroperoxide process, where either / fZ-butanol (see Butyl alcohols) or styrene (qv) is a co-product. Research continues in an effort to develop a direct oxidation process to be used commercially. 

Hydroperoxide Process. The hydroperoxide process to propylene oxide involves the basic steps of oxidation of an organic to its hydroperoxide, epoxidation of propylene with the hydroperoxide, purification of the propylene oxide, and conversion of the coproduct alcohol to a useful product for sale. Incorporated into the process are various purification, concentration, and recycle methods to maximize product yields and minimize operating expenses. Commercially, two processes are used. The coproducts are / fZ-butanol, which is converted to methyl tert-huty ether [1634-04-4] (MTBE), and 1-phenyl ethanol, converted to styrene [100-42-5]. The coproducts are produced in a weight ratio of 3—4 1 / fZ-butanol/propylene oxide and 2.4 1 styrene/propylene oxide, respectively. These processes use isobutane (see Hydrocarbons) and ethylbenzene (qv), respectively, to produce the hydroperoxide. Other processes have been proposed based on cyclohexane where aniline is the final coproduct, or on cumene (qv) where a-methyl styrene is the final coproduct. 

Glass is a material having properties that provide attributes for many commercial products. As some of these products reach the end of thek useful life and are discarded, there is often the opportunity to have the glass recycled into other useful products. In many respects, this alternative is preferred over the glass entering a municipal waste stream for landfill disposal. 

Economic Aspects and Uses. Production and sales values for high purity sodium hydrosulfide are Hsted ia Table 1. These figures exclude the low purity material produced by oil refiners, beHeved to be sold primarily to pulp mills. Estimates of uses of NaHS ia the United States for 1994 are as shown (3,4) ... 

Economic Aspects and Uses. Production and pricing information for Na2S through 1991 are Hsted in Table 2. U.S. production of sodium sulfide increased rapidly from 1965 through 1972 and then began to decrease. The last year that the U.S. Bureau of the Census released official production figures was in 1974 because at that time there were only three producers of sodium sulfide. Estimates indicate that 1991 production fell to the levels of the late 1950s. List prices have increased since 1974 as sulfur and sodium hydroxide prices have increased. 

Uses ndReactions. Nerol (47) and geraniol (48) can be converted to citroneUol (27) by hydrogenation over a copper chromite catalyst (121). In the absence of hydrogen and under reduced pressure, citroneUal is produced (122). If a nickel catalyst is used, a mixture of nerol, geraniol, and citroneUol is obtained and such a mixture is also useful in perfumery. Hydrogenation of both double bonds gives dimethyl octanol, another useful product. 

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