Soft sulfation process

To control the complex process of cooking by the sulfate process cellulose, by means of a computer, it is necessary to have a mathematical model of the process. To obtain this model for the process of cooking by the sulfate process cellulose from a mixture of soft and hardwood and deciduous trees, we have used a fractional factorial experiment. It included these seven factors xi consumption of active lye, % Na20 on completely dry wood X2 cooking temperature, °C ... 

Aluminum sulfate is a starting material in the manufacture of many other aluminum compounds. Aluminum sulfate from clay could potentially provide local sourcing of raw materials for aluminum production. Processes have been studied (24) and the relative economics of using clay versus bauxite have been reviewed (25). It is, however, difficult to remove impurities economically by precipitation, and purification of aluminum sulfate by crystallization is not practiced commercially because the resulting crystals are soft, microscopic, and difficult to wash effectively on a production scale (26—28). 

Prior to the bating process, the hides are delimed with ammonium sulfate and/or ammonium chloride. Proteases are then appUed. The early preparation proposed by Rn hm was pancreatic trypsin. The use of a bating enzyme makes the hides soft and supple to prepare them for tanning. A new microbial protease, Pyrase 250 MP (82) (Novo Nordisk A/S) has been found to be a promising substitute for pancreatic trypsin [9002-07-7] which is more expensive because it must be extracted from pancreatic glands. 

Plaster of Paris has long been used as a casting material, a cement, and a mortar. If mixed with water, plaster of Paris forms a very soft and pliable mixture. After a very short time, lasting only 5-8 minutes, the wet, pliable mixture sets, that is, it hardens into a stable, firm solid. The setting process entails the incorporation of water molecules (a process known as hydration) into the calcium sulfate hemihydrate and the consequent formation and crystallization of hydrated sulfate of calcium. In other words, when water is added to plaster of Paris, the two combine, again forming gypsum, which soon crystallizes into a hard solid mass ... 

Direct analysis of sulfated steroids by MS has become common, especially since the advent of soft ionization techniques (Bowers and Sanaullah, 1996 Murry et al., 1996). The gentle process of proton... 

Although silver is not treated by solvent extraction in any of the flow sheets, silver is recovered from aqueous solution in several other situations. For these processes, Cytec developed reagents with donor sulfur atoms to extract this soft element. For example, tri-isobutylphosphine sulfide (CYANEX 47IX) extracts silver from chloride, nitrate, or sulfate media selectively from copper, lead, and zinc [32]. The silver is recovered from the loaded organic phase by stripping with sodium thiosulfate, and the metal recovered by cementation or electrolysis. Silver can also be extracted from chloride solution by a dithiophosphinic acid (CYANEX 301) [33]. 

Attention has been focused recently on sedimentary microbial reduction of sulfate. This process neutralizes atmospheric sulfuric acid deposited into soft-water lakes (8-10) through the production of two equivalents of alkalinity per mole of sulfate reduced (11). 

X-ray absorption study of tribofilms generatedfrom a combination of ZDDP and borate-sulfonate RMs was used to determine the chemistry of tribochemical films at the surface and the bulk The calcium phosphate content in the tribofilm generated from either ZDDP + borate-sulfonate RMs or from ZDDP + calcium sulfonate soft-core RMs is similar (Varlot et al., 2001). Calcium sulfonate S(+5) undergoes disproportion reaction to form sulfate S(+6) and sulfite S(+4), and the presence of ZDDP affects the disproportion process. Close to the steel surface, the... 

A patented process [22.7, 22.8] produces a milk of lime with a median particle size of less than 1 pm, and a high chemical reactivity. To a large extent it can be handled as a liquid rather than as a suspension. The process uses highly reactive quicklime with low CaCOa and S contents and with a maximum particle size of 5 mm. The water should be relatively soft (less than 0.2 g CaCOa/l) and have a low sulfate content. A slaking temperature of 70 to 80 °C is used. 

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