Document OzbOwq0JKzJgx9MQ6JrgdKBxj

manufacture e.' l.i,'.-t chloreethar*. If mill'd oxides of zinc, manganese, Aceton* etc., all vinyl chlbnde ^ used to pro- chroi.-iiu-n, anj aluminum ire used duto polyvinyl chloride or co as the catalysts, pressure of 300 atm Average annual production: 1 x 10* polymers of vinyl chloride end other at 300 *C is required With a copper kg; value in U5S: 7 x 10* monomers. catalyst, a lower pressure of 7S atm Polyvinyl chloride is used exten suffices at 300 *C. Less by-product is sively in the building and construc formed at the lower pressures. Process: Acetone is one product tion industry. 0* piping, lloor coven from the peroxidation of cumene (see ini, end exterior surface, weather Phenol! it is also manufactured by resistant covering. It is used in the in Uses: Smalt amounts of methyl the catalytic dehydrogenation of sulation of electrical wiring in alcohol are used directly as a solvent isopropyl alcohol using a *rass or packaging as a film, in apparel as a but most of the methyl alcohol pro copper catalyst and 3 atm pressure at coating on fabric to impart a sup duced q raw material for the manu 500 *C. Byproduct hydrogen is reeov--, posedly improved esthetic appear facture of other compounds. These tied, acetone distilled off. and unre- ance or, more practically, for rail* include formaldehyde (which seel acted alcohol recycled. coats, etc. Polyvinyl chloride is used acetic acid--by carboxylation. meth for water- botes, for tarpaulins yl tertiary butyl ethe, dimethyl tern Uses: To some extent directly as a (sometimes with a fabric backing! in phthalate, methyl methacrylate, and solvent for example in the manufac some paints, and for many other pur methyl derivatives such as the ture of acetate rayon, but largely as a poses too numerous to describe in amines and the halides. As a blend raw material for the manufacture of detail. Polyvinyl chloride is the single with tertiary butyl alcohol methyl derivatives. Some derivatives are most important polymeric substance alcohol has some promise as an oc useful as solvents themselves, and at in use today. tane booster in gasolines. precursors alto: methyl isobutyl ketone, methyl bobutyl carbinol, Remarks: The alleged car diacetone alcohol. Acetone is a raw cinogenicity of vinyl chloride il Remarks: The carbon monoxide material for the manufacture of lustrates that political influence of and hydrogen raw materials are ob methyl and higher methacrylates and vociferous minorities can overwhelm* tained from synthesis gas, a mixture of some pharmaceuticals. the need for proper attention to of carbon monoxide and hydrogen in scientific questions In deciding approximately the correct propor socially important issues. The facts tions for methyl alcohol synthesis. are these. Humans exposed to vinyl Synthesis gas is obtained by treating chloride by skin contact at frequent methane or other hydrocarbons (lor intervals for long periods of time will example, the heavy hydrocarbon sometimes develop a cancer--sar residues from petroleum refining) Remarks: Acetone is another of the few chemicals involved in recent geopolitical history Celluiste nitrate is an explosive and it used as 'smokeless powder*. Its manufacture coma of the liver. Experimental with carbon dioxide and water at 800 during World War I required large animals exposed to vinyl chloride C in the presence of a nickel amounts of acetone as a -solvent. At vapor at fairly low concentrations catalyst- When properly controlled, that time, the major source of ace will also develop liver sarcomas. The the mator products are carbon tone was from the destructive distilla f limited evidence of human exposure monoxide and hydrogen. tion of wood. The requirements for to vinyl chloride vapor strongly sup In the synthesis of methyl alcohol acetone were so great w England in gests that such exposure cannot prev the maior by-products are dimethyl 1915-1916 that English forests were duce liver sarcomas Vet. without re ether and higher alcohols. almost exhausted. Without the wood, quiring any further scientific Methyl tertiary butyl ether is used black powder. a militarily much less evidence, vinyl chloride antagonists primarily as an octane bocster in desirable explosive, would have to be in the United States were able to gasolines. It is also used in substituted. Through the efforts of politically force the vinyl chloride in laboratories in place of the more the editor of the Manchester Cuar- dustry to take the steps necessary to common .ethers, diethyl ether and ditri newspaper. David Lloyd Ceorge. preclude worker exposure to vinyl isopropyl ether, because, unlike these England's Prime Minister, asked a chloride vapor--at costs reflected in ethers it has little tendency to form young chemistry professor at the otherwise unnecessary price in ether peroxides on standing in the University of Manchester if he could creases. presence of air. Since ether peroxides find a solution. In lets than three are quite unstable and detonate oc weeks he found another source: the Methyl Alcohol casionally with only a slight touch or controlled fermentation of com impact the use of methyl tertiary starch. Refusing a proffered knight butvl ether at a solvent in laboratory hood, the professor gained the pro Avenge annual production: 3.4 x 10* work can be expected to increase. mise of an unspecified favor to be kg value m USS: 1 x 10* Methyl alcohol is an intoxicant granted later. By late 1917. a pro end is found in trace amounts in all pitious time, the Foreign Secretary, Process: By direct synthesis using lermented and even in distilled Arthur lames Balfour, promulgated carbon monoxide and hydrogen to alcoholic beverages. When present in the Balfour Declaration as the favor form methyl alcohot larger amounts by deliberate addi to the professor, Cha>m Weitmanrt tion. it causes blindness and even Most historians agree that the CO + 2H,--wCH.OH death when ingested. Balfour Declaration was an essential 110 4 t V nakfehyde is the controlled oxida for several minutes until all o> th- tion of methane or higher hydro phenol has been rubbed and ,eraie annual proiJuction: 2-7 x 10* valve in USi: 5.5 * 10* carbons, the latter givmg a variety of products that must be separated. This alternate is practical only when there scrubbed away. Alternate syntheses fry phenol in clude bnne and benzene as the raw Process: Catalytic vapor phase ox idation of methanol. using mixture* Jt air and methanol. Silver or copper screen catalyst can be used, but a mixed outside catalyst (oxides of molybdenum, iron, vanadium) gives better yields--at higher cost is a good market for the other prod ucts. , Formaldehyde polymerizes readily to the tnmer, trioxane, and to higher not as weH characterized polymers. It is often sold as a monomer in water solution with methanol as an in hibitor to minimize polymerization. materials. The bnne is electrolyzed to chlorine and sodium hydroxide (which seel chlorine plus benzene with an iron catalyst forms monte chlorobenzene (if controlled) The chlorobenzene reacts with sodium hydroxide to form phenol and sodium chloride, under acidic condi Uses: Formaldehyde i* a raw material for the manufacture of a wide variety of compounds. These in clude urea formaldehyde resins, phenol formaldehyde resins, polyacetal resins, butanediol, hex amethylenetetramine. melamine for maldehyde resins, tetrahydrofuran, and polyols such as pentaerythritrol and 2-ethyl-2(hydroxymethyl)-1, Trimane, however, readily "monomerizes* in the pretence of acid. Phenol Average annual production: 1.2 x 10* kg; value in U$V 5 x 10* tions. The sodium chloride is recy cled to chlorine and sodium hydrox ide. and so on. In the alkaline hydrolysis of chlorobenzene, diphenyl ether is the expected major side product. Its formation is minimized by the deliberate addition of diphenyl ether, an example of the application of le Chateliefs principle. Another alternate is the oxidation >propanediol. The resins are partially copolymeriztd forms of their named components; used as adhesives, the Process: The peroxidation of cumene (isopropyl benzene) yields both phenol and acetone as the ma jor products; two steps are required; of toluene to benzoic acid followed by the oxidation of this acid in the presence of a copper catalyst to phenol and carbon dioxide. This syn thesis it industrially useful only when resins are moted with other solids (such as flakas of wood or other CHtCH(CHi)t + 0,-C.M,CtCH,),OOM the price of toluene is low and that of phenol high. 4* I fibrous material) and the mixture heated under pressure. The resins then polymerize completely, binding the fibrous components to form a tough, durabla structural material. The other compounds mentioned above are themselves the starting points for a wide variety of still other useful compounds; note that most of these derivatives are characterized by two or more active functional The process requires a pH near neutrality and 110 *C air supplies the needed oxygen. In the second'step under acidic conditions, cumene hydroperoxide is decomposed into phenol and acetone. Other products include methylstyrene (sold or catalytically hydrogenated to cumene and recycled) and acetophenona Cumene is formed by the catalytic addition of benzene to propylene. Both are products trom petroleum; often phenol plants are located near oil wells or shipping ports and are owned by the petroleum manufac turer. Some phenol is obtained as a by product of coke manufacture. (soldi unreacted cumene is recycled. 'Vinyl CMoridg^ i groups, amine or hydroxy in the ex amples mentioned, which provide the means for the preparation of a variety of derivatives. Uses: As a raw material for the manufacture of phenol formalde hyde resins (see Formaldehyde) Sim ilarly. for the manufacture of bispherv Average annual production: 23 1C' kg; value in. USi. 13 x 10* x ol A (4,4`-isopropylidene diphenoll Process: 1.2-dichloroethsne (soRemarks: The oxidation of from phenol and acetone--used in called dichloroethylene) is dehvdrte methanol to formaldehyde can be resin manufacture. Similarly, ter chlorinated using a charcoal or thought of as involving two reactions, polycarbonate resins. Some alkyl pumice catalyst at 3 atm and 500 *C. dehydrogenation to form for derivatives of phenol can be used as The product vinyl chloride is quickly maldehyde, an endothermic process, surfactants- Phenol is used for the quenched with cold 1,2-dichlor and the oxidation of methanol to for manufacture of adipic acid and of- ethane and then separated from the maldehyde and other products, an caprolactam, NHtCH,),CO; both are queryhant and from minor by-prod exothermic process. For optimum for precursors of nylon. ucts bv distillation. maldehyde production, the tempera The 1.2-dichloroethane is itself pro ture should be about 500 *C to Remarks: The unique toxicity of duced in the same plant or in a achieve this, the ratio of air and phenol is not well-known--it is rapid separate but adiacent plant bv the methanol introduced into the reac ly absorbed through the intact skin addition of chlorine to ethylene in tion region is balanced so that the and unless the area of skin affected a the presence of 1.2-dibromoethane. endo- and exothermic reactions, quite small the effect is known to be using an aluminum chloride or iron along with radiant heat loss, maintain tatai wMun it little as two minutes. (III) chloride catalyst at 50 *C. the reaction region at the optimum The remedy it immediate and temperature. vigorous rubbing end scrubbing Uses: txccpt for some very small An alternate preparation of foe under flowing water with a doth pad uses 4s the raw material for the *" rXi OCC 041454