CO, production

The role of iodides, especially methyl iodide, is not known. The reaction occurs scarcely at all without iodides. Impurities and co-products are poorly reported in the patent Hterature on the process. 

Simply looking at the feedstock prices or price ratios is iasufficient to accurately identify the most attractive feedstock because the values of all of the co-products and by-products must also be taken iato account. This is usually accompHshed by calculating the cost to produce ethylene with all other coproduct and by-product yields credited against the cost of ethylene. An example of the cost of ethylene is presented ia Table 4. The cash costs of ethylene from various feedstocks are compared for the months of July and November of 1991. Cash costs reflect all plant manufactufing costs except depreciation and are a measure of the out-of-pocket cash costs generated by the operation. 

Typical COED syncmde properties are shown in Table 12. The properties of the oil products depend heavily on the severity of hydroprocessing. The degree of severity also markedly affects costs associated with hydrogen production and compression. Syncmdes derived from Western coals have much higher paraffin and lower aromatic content than those produced from Illinois coal. In general, properties of COED products have been found compatible with expected industrial requirements. 

The equiHbrium approach should not be used for species that are highly sensitive to variations in residence time, oxidant concentration, or temperature, or for species which clearly do not reach equiHbrium. There are at least three classes of compounds that cannot be estimated weU by assuming equiHbrium CO, products of incomplete combustion (PlCs), and NO. Under most incineration conditions, chemical equiHbrium results in virtually no CO or PlCs, as required by regulations. Thus success depends on achieving a nearly complete approach to equiHbrium. Calculations depend on detailed knowledge of the reaction network, its kinetics, the mixing patterns, and the temperature, oxidant, and velocity profiles. 

The reaction is mn for several hours at temperatures typically below 100°C under a pressure of carbon monoxide to minimise formamide decomposition (73). Conversions of a-hydroxyisobutyramide are near 65% with selectivities to methyl a-hydroxyisobutyrate and formamide in excess of 99%. It is this step that is responsible for the elimination of the acid sludge stream characteristic of the conventional H2SO4—ACH processes. Because methyl formate, and not methanol, is used as the methylating agent, formamide is the co-product instead of ammonium sulfate. Formamide can be dehydrated to recover HCN for recycle to ACH generation. 

Several types of chemical processes are used to produce potassium sulfate. The traditional Mannheim process is used in countries that produce KCl but lack a natural source of sulfate salts for converting the KCl to K2SO4. In this process, KCl reacts with sulfuric acid to yield K2SO4 and HCl as a co-product. 

This process or a variation called the Hargreaves process is also used in areas where sulfuric acid is available as a by-product or where co-product HCl is needed for the production of other chemicals. 

Potassium Nitrate. Potassium nitrate [7757-79-17, KNO, is produced commercially in the United States based on the reaction of potassium chloride and nitric acid (qv) (35). Ammonia (qv) oxidation is the source for the nitric acid and the reaction is manipulated chemically to yield chlorine as a co-product. The process is operated at an elevated temperature to drive the reaction to completion according to the following equation ... 

This process has defects such as co-production of acetone and a low yield of ahyl alcohol. 

Lower aHphatic amines can be prepared by a variety of methods, using many different types of raw materials. By far the largest commercial appHcations involve the reaction of alcohol with ammonia to form the corresponding amines. Other methods are employed depending on the particular amine desired, raw material availabiHty, plant economics, and the abiHty to seU co-products. The foUowing manufacturing methods are used commercially to produce the lower aLkylamines. Table 5 gives plant and capacity information for these methods. 

Dehydrogenation. Before the large-scale availabiUty of acetone as a co-product of phenol (qv) in some processes, dehydrogenation of isopropyl alcohol to acetone (qv) was the most widely practiced production method. A wide variety of catalysts can be used in this endothermic (66.5 kj/mol (15.9 kcal/mol) at 327°C), vapor-phase process to achieve high (75—95 mol %) conversions. Operation at 300—500°C and moderate pressures (207 kPa (2.04 atm)) provides acetone in yields up to 90 mol %. The most useful catalysts contain Cu, Cr, Zn, and Ni, either alone, as oxides, or in combinations on inert supports (see Catalysts, supported) (13-16). 

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. 

The vapor cloud of evaporated droplets bums like a diffusion flame in the turbulent state rather than as individual droplets. In the core of the spray, where droplets are evaporating, a rich mixture exists and soot formation occurs. Surrounding this core is a rich mixture zone where CO production is high and a flame front exists. Air entrainment completes the combustion, oxidizing CO to CO2 and burning the soot. Soot bumup releases radiant energy and controls flame emissivity. The relatively slow rate of soot burning compared with the rate of oxidation of CO and unbumed hydrocarbons leads to smoke formation. This model of a diffusion-controlled primary flame zone makes it possible to relate fuel chemistry to the behavior of fuels in combustors (7). 

Most barium compounds are prepared from reactions of barium carbonate [513-77-9] BaCO, which is commercially manufactured by the "black ash" process from barite and coke ki a process identical to that for strontium carbonate production. Depending on the co-product, soda ash and/or carbon dioxide are also consumed. 

Wlien solid soda ash is used to supply all the carbonate v alues in the precipitation step (eq. 9), a ca 10% Na2S solution results from the primary filtration step wliich can be concentrated to 40% Na2S in a three-effect evaporator train. Final concentration to 60%Na2S occurs in a high v acuurn single-effect evaporator. Hiis concentrated solution can then be fed to a Baker to produce a 60% sodium sulfide flake wliich is sold as co-product. 

Processes for hydrogen gasification, hydrogen pyrolysis, or coking of coal usually produce Hquid co-products. The Hygas process produces about 6% Hquids as benzene, toluene, and xylene. Substitution of petroleum residuum for the coal-derived process oil has been used in studies of coal Hquefaction and offers promise as a lower cost technology (104). 

Ethane feed gives the lowest cost of production and the lowest capital investment. As the feeds become successively heavier, cost of production increases as well as the capital investment required. Depending on the cost of feedstock and the value of the co-products, processing heavier feedstocks can lead to lower returns on investment. Table 13 shows the effect on capital investment for various feedstocks as well as for a range of capacities. 

All wastes generated, as a result of manufacture of the ABC Co. product should be disposed of properly. ... 

The state environmental agency should be notified that production has stopped if permits were required to manufacture the ABC Co. product. ... 

Is the equipment to be used for manufacturing ABC Co. products greater than ten years old (note specific equipment) ... 

Are the ABC Co. products currently contracted for manufacture or repackaging specifically listed m the contractual agreement (Please attach a list of pounds received and shipped of ABC Co. owned raw materials, intermediates and finished products for the last twelve months.) ... 

This checklist presents a number of questions to assist in identifying environmental and health and safety issues at facilities where ABC Co. product(s) are manufactured (all or m part) by another company or where ABC Co. produces) are licensed to another company. 

Figure 13.1 Schematic diagram of the blast furnace for the co-production of liquid lead and zince...

Modern processes for strong acid are based on direct oxidation of ammonia with air or oxygen, with the first two steps being similar to the weak acid process. Various processes exist allowing co-production of weak and strong acid. 

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