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Tons, formation

Period II lasted 7 years oil yield was 4,500,000 tons and the amount of formation water produced was 2,900,000 tons. Formation pressure declined from 40 kg/cm to 15 kg/cm. Characteristically for this period, the water in the liquids recovered increased, then, towards the end of the period, decreased again. Gas dissolved in the oil provided the basic drive during this period. Forces of molecular cohesion between the oil and the reservoir rocks are weakened and oil mobility enhanced when water cut stays within the 35-50% range. [Pg.16]

In this equation, y is the charge equilibrium factor, is the probability of exci-ton formation from one electron-hole pair, and jjpl is the quantum yield for the photoluminescence. [Pg.372]

Of all the monosaccharides d (+) glucose is the best known most important and most abundant Its formation from carbon dioxide water and sunlight is the central theme of photosynthesis Carbohydrate formation by photosynthesis is estimated to be on the order of 10 tons per year a source of stored energy utilized directly or indi rectly by all higher forms of life on the planet Glucose was isolated from raisins m 1747 and by hydrolysis of starch m 1811 Its structure was determined in work culmi nating m 1900 by Emil Fischer... [Pg.1032]

It was not until the twentieth century that furfural became important commercially. The Quaker Oats Company, in the process of looking for new and better uses for oat hulls found that acid hydrolysis resulted in the formation of furfural, and was able to develop an economical process for isolation and purification. In 1922 Quaker announced the availability of several tons per month. The first large-scale appHcation was as a solvent for the purification of wood rosin. Since then, a number of furfural plants have been built world-wide for the production of furfural and downstream products. Some plants produce as Httie as a few metric tons per year, the larger ones manufacture in excess of 20,000 metric tons. [Pg.75]

Pusher centrifuges require high feed concentrations to enable the formation of a sufficiently rigid cake to transmit the thmst of the piston. The diameters vary from 150 to 1400 mm, the stroke frequency from 20 to 100 strokes per minute, and the soHds handling capacities up to 40 metric tons per hour or more. [Pg.414]

Economic Aspects. U.S. capacity for production of merchant sodium dithionite (soHds basis) was estimated at 93,000 metric tons in 1994. There are three North American producers of sodium dithionite. Hoechst Celanese is the largest producer (68,000 tons capacity) with two formate production locations and one zinc process location. Olin (25,000 t capacity) produces solution product only at two locations using both the amalgam and electrochemical processes. In 1994, Vulcan started a small solution plant in Wisconsin using the Olin electrochemical process. In addition, it is estimated that 13,000 t/yr is produced at U.S. pulp mills using the Borol process from sulfur dioxide and sodium borohydride. Growth is estimated at 2—3%/yr. The... [Pg.150]

Free-Radical-Initiated Synthesis. Free-radical-initiated reactions of hydrogen sulfide to alkenes are commonly utilized to prepare primary thiols. These reactions, where uv light is used to initiate the formation of hydrosulfuryl (HS) radicals, are utilized to prepare thousands of metric tons of thiols per year. The same reaction can be performed using a radical initiator, but is not as readily controlled as the uv-initiated reaction. These types of reactions are considered to be anti-Markownikoff addition reactions. [Pg.10]

The only disperse brown of commercial importance is Disperse Brown 1 (101), which in 1988 had sales in excess of 2.3 million (production 317 tons). A method stiU. in use to produce navy and black shades economically on acetate involves formation of the dye direcdy on the substrate (azoic dyeing). [Pg.449]

Solution mining produced nearly 23 million metric tons of salt in 1989 representing more than half of the total U.S. salt production (14). Salt brine is made from bedded salt at more than 18 different locations and from 17 salt domes (15). Bedded salt of the salina formation is the most widely and intensively exploited by solution mining. Enormous reserves of salina salt are available. Cost of solution mining salt is usually less than the cost of salt produced by dry mining. The method is particularly good where salt deposits are deep and dry mining would not be feasible. [Pg.408]

The hydrolysis of nitriles can be carried out with either isolated enzymes or immobilized cells. Eor example, resting cells of P. chlororaphis can accumulate up to 400 g/L of acrylamide in 8 h, provided acrylonitrile is added gradually to avoid nitrile hydratase inhibition (116). The degree of acrylonitrile conversion to acrylamide is 99% without any formation of acryUc acid. Because of its high efficiency the process has been commercialized and currentiy is used by Nitto Chemical Industry Co. on a multithousand ton scale. [Pg.344]

Nucleophilic aromatic substitution of the anion from ary lace ton itrile 113 on the dichloroni-trobenzene 114 results in replacement of the para halogen and formation of 115. Reduction of the nitro group gives the corresponding aniline (116). Acylation of the amine with 3,5-diiodoacetylsa-licylic acid 117 by means of the mixed anhydride formed by use of ethyl chloroformate, gives, after alkaline hydroly.sis, the anthelmintic agent closantel (118) [28]. [Pg.36]

Another problem is when the carbon dioxide content of natural gas is too high and must be lowered to produce pipeline-quality gas. Although the current practice is to vent this CO, sequestration of CO, in underground geologic formations is being considered. Already, in the Norwegian sector of the North Sea, CO, has been injected into saline aquifers at a rate of 1 million tons a year to avoid... [Pg.915]

About 8(1 percent of the electric energy used in the United States is derived from stored energy in coal. The stored energy has its origin in photosynthesis. Coal is the end product of the accumulation of plant matter in an oxygen-deficient environment where burning is thwarted. Formation takes millions of years. Proven reseiwes of coal in the United States are upwards of 500 billion tons, a reserve so great that even if coal continues to be burned at a rate of over one billion tons per year, the reserves will last for hundreds of years. [Pg.1096]

These materials are essentially combustion improvers and tend to have fairly simple formulations (e.g., 3% copper chloride, 7% manganese chloride, 90% ammonium chloride). They are designed to change the crystalline structure within the clinker crystal lattice and raise the clinker eutectic point, thus minimizing the formation of noncombustible clinker, residual ash, and other deposits. Feed rates are approxiimately 0.5 to 2.0 lb per bone-dry ton. [Pg.683]

Darwin, C. (1896). "The Formation of Vegetable Mould Through the Action of Worms with Observations of their Habitats," pp. 305-313. D. Apple-ton, New York. [Pg.191]

In Figure 3 the merits of the two processes for p-xylene oxidation are compared. The main disadvantages of the Eastman Kodak/Toray cooxidation method are the need for a cosubstrate (acetaldehyde of methylethylketone) with concomitant formation of a coproduct (0.21 ton of acetic acid per ton product) and high catalyst concentration. The Amoco MC process, on the other hand, has no coproduct and much lower catalyst concentrations but has the disadvantage that the bromide-containing reaction mixture is highly corrosive, necessitating the use of a titanium-lined reactor. [Pg.281]

Other small monomeric GTPases (eg, ARF, Rab, Ras, and Rho) are important in various cellular processes such as vesicle formation and transport (ARF and Rab see below), cettain growth and differentiation processes (Ras), and formation of the actin cytoskele-ton. A process involving GTP and GDP is also crucial in the ttanspott of ptoteins across the membrane of the ER (see below). [Pg.501]

In addition to nonheme iron complexes also heme systems are able to catalyze the oxidation of benzene. For example, porphyrin-like phthalocyanine structures were employed to benzene oxidation (see also alkane hydroxylation) [129], Mechanistic investigations of this t3 pe of reactions were carried out amongst others by Nam and coworkers resulting in similar conclusions like in the nonheme case [130], More recently, Sorokin reported a remarkable biological aromatic oxidation, which occurred via formation of benzene oxide and involves an NIH shift. Here, phenol is obtained with a TON of 11 at r.t. with 0.24 mol% of the catalyst. [Pg.101]

Similar reactions with primary and secondary amines result in the formation of 3-aUcylamino- or 3-dialkylamino-l-butyne in 30-80% yield (TON = 3-9) [243-247]. In one example, the TOP could be estimated as 0.2 h" [246]. Enamines were proposed as reaction intermediates. It was later shown that enamines effectively react with terminal aUcynes, including acetylene, to afford the expected aminoalkynes without catalyst or, more rapidly, sometimes exothermically, in the presence of CujCf [248]. Aromatic amines do not react under the same conditions. However, in the presence of organic acids, e.g. acetic acid, 3-arylamino-l-butynes can be isolated in moderate yields (Eq. 4.59) [246, 247, 249]. [Pg.118]

Formation of polynuclear lead species with parameters close to isolated lead bromophenoxides during DPC synthesis was found by EXAFS of frozen active reaction mixtures (Pb-0 = 2.34 A, Pb Pb = 3.83 A). Noteworthy, in samples of final reaction mixtures, where catalyst was inactive, short Pb Pb distances were absent. These polynuclear compounds have been tested as lead sources in large-scale runs (small scale reactions were inconclusive due to heterogeneity of reaction mixtures because these compounds are less soluble than PbO). It was found that the use of lead bromophenoxides instead of PbO increases both Pd TON (by 25-35%), and reaction selectivity (from 65 - 67 % to 75 - 84 %). Activity of different lead bromophenoxides was about the same (within experimental error) but the best selectivity was observed for complex Pb602(0Ph)6Br2. Therefore, the gain in selectivity vs. loss due to additional preparation step should be analyzed for practical application. [Pg.191]


See other pages where Tons, formation is mentioned: [Pg.262]    [Pg.276]    [Pg.144]    [Pg.130]    [Pg.262]    [Pg.276]    [Pg.144]    [Pg.130]    [Pg.1048]    [Pg.229]    [Pg.524]    [Pg.44]    [Pg.244]    [Pg.481]    [Pg.7]    [Pg.280]    [Pg.1605]    [Pg.210]    [Pg.1033]    [Pg.343]    [Pg.185]    [Pg.58]    [Pg.305]    [Pg.94]    [Pg.165]    [Pg.439]    [Pg.176]    [Pg.219]    [Pg.422]    [Pg.739]    [Pg.767]    [Pg.8]    [Pg.115]    [Pg.102]   


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