Contact process, for sulfuric acid

Figure 2.3 Contact process for sulfuric acid manufacture.

Fig. 25.9. Schematic flow diagram of a double absorption contact process for sulfuric acid manufacture.

The single absorption contact process for sulfuric acid is characterized by four main process steps gas drying, catalytic conversion of S02 to S03, absorption of S03, and acid cooling. The maximum S02 conversion for a single absorption plant is about 97.5-98 percent. By adding a second S03 absorber with one or two catalyst beds between absorbers, the S02 conversion can be increased to 99.5-99.8 percent or even as high as 99.9 percent with a cesium-promoted catalyst, resulting in lower S02 emis-... 

Granular triple super phosphate MAP DAP Power generation Contact process for Sulfuric acid Wet process for phosphoric acid Acetic acid-standard method... 

For reactions with a positive AG° there are ways to increase the conversion. One standard method is to remove products in an intermediate step. This procedure is used in the double absorption contact process for sulfuric acid where sulfur trioxide is removed after the gas passes through two-packed bed reactors before entering the last two reactors. 

In the finely divided state platinum is an excellent catalyst, having long been used in the contact process for producing sulfuric acid. It is also used as a catalyst in cracking petroleum products. Much interest exists in using platinum as a catalyst in fuel cells and in antipollution devices for automobiles. 

Haber process for ammonia. Another is finely divided vanadium pentoxide, V205, which is used in the contact process for the production of sulfuric acid ... 

CAT-OX [Catalytic oxidation] An adaptation of the Contact process for making sulfuric acid, using the dilute sulfur dioxide in flue-gases. A conventional vanadium pentoxide catalyst is used. Developed by Monsanto Enviro-Chemical Systems, and operated in Pennsylvania and Illinois in the early 1970s. 

IPA [Interpass absorption] Also called Double absorption, and Double catalysis. An improved version of the Contact process for making sulfuric acid, by which the efficiency of the conversion of sulfur to sulfuric acid is increased from 98 percent to over 99.5 percent. 

Knietsch An early version of the Contact process for making sulfuric acid. Developed by R. Knietsch at BASF, Ludwigshaven. 

Schroder-Grillo Also known as Grillo-Schroder. An early version of the contact process for making sulfuric acid. The catalyst was magnesium sulfate impregnated with platinum. The process was invented in 1899 by A. Hecksher at the New Jersey Zinc Company and first used at its plant in Mineral Point, WI, in 1901 this was the first use of the contact process in the United States. In the United Kingdom it was first used in Widnes in 1917. See also Mannheim (2). 

N2(g) + 3H2(g) 2NH3(g) AH° = —92 kj/mol Because the reaction is exothermic, heat is released as the reaction proceeds. Le Chatelier s principle predicts that the yield of ammonia is greater at lower temperatures. Just as in the contact process for manufacturing sulfuric acid, however, high yield is not the only important factor. The rate of reaction for ammonia synthesis is too slow at low temperatures. 

Sulfur dioxide is made as part of the contact process for making sulfuric acid (Chapter 2, Section 2.2). Sulfur and oxygen are burned at 1000°C. Sulfur dioxide can be made by oxidation of various metal sulfides or hydrogen sulfide, or it can be made from calcium sulfate or used sulfuric acid as well. 

The lead-chamber process supplied the world s need for sulfuric acid for a century and a half. In the late nineteenth century, the contact process replaced the lead-chamber process. The contact process utilized sulfur dioxide, SOj, which was produced as a byproduct when sulfur-bearing ores were smelted. The contact process was named because the conversion of sulfur dioxide to sulfur trioxide, SO3, takes place on contact with a vanadium or platinum catalyst during the series of reactions ... 

C. Winkler Invention of the contact process for the synthesis of sulfuric acid. 1879... 

The modern industrialized world would be inconceivable without catalysts. Catalysis is a multidisciplinary area of chemistry, particularly industrial chemistry where around 85% of all products pass through at least one catalytic stage. Anyone who is involved with chemical reactions will eventually have something to do with catalysts. For example, the contact process for the production of sulfuric acid was introduced as early as 1880. After World War II, some catalysts for crude oil processing appeared on the US and European markets and, from an environmental standpoint, they became crucial from 1970 onwards because of their contribution to the protection of the environment and thus to a generally higher standard of living. 

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