Inorganic sulfur compounds

Natural gas contains both organic and inorganic sulfur compounds that must be removed to protect both the reforming and downstream methanol synthesis catalysts. Hydrodesulfurization across a cobalt or nickel molybdenum—zinc oxide fixed-bed sequence is the basis for an effective purification system. For high levels of sulfur, bulk removal in a Hquid absorption—stripping system followed by fixed-bed residual clean-up is more practical (see Sulfur REMOVAL AND RECOVERY). Chlorides and mercury may also be found in natural gas, particularly from offshore reservoirs. These poisons can be removed by activated alumina or carbon beds. 

H. Reactions with Suleur and Sulfur Compounds 1. Elemental Sulfur and Inorganic Sulfur Compounds... 

Sulfur in crude oils is mainly present in the form of organosulfur compounds. Hydrogen sulfide is the only important inorganic sulfur compound found in crude oil. Its presence, however, is harmful because of its corrosive nature. Organosulfur compounds may generally be classified as acidic and non-acidic. Acidic sulfur compounds are the thiols (mercap-tans). Thiophene, sulfides, and disulfides are examples of non-acidic sulfur compounds found in crude fractions. Extensive research has been carried out to identify some sulfur compounds in a narrow light petroleum fraction.Examples of some sulfur compounds from the two types are ... 

An inspection of Tables 1 and 2 shows that appropriate solvents for lithium batteries mainly belong to classes 6 and 7 and include cyclic (EC, PC) and open-chain (DMC, MEC, DEC, MPC) esters and ethers (DIOX, DME, THF) as well as inorganic sulfur compounds (S02, SOCl2). These sulfur compounds are mainly used as liquid cathode materials, simultaneously serving as solvents (S02C12, SOCl2) or cosolvents (S02) in primary or secondary lithium batteries. Recent developments of solvents include... 

G. Brauer (ed.), Handbuch der Prdparativen Anorganischen Chemie, Vol. 1, Enke, Stuttgart, 1975 (Preparation of basic inorganic sulfur compounds). 

Treatment of Solid Materials Containing Inorganic Sulfur Compounds (R. Tichy)... 

PEC. The patent includes the production method for the biocatalyst, with a characteristic inhibitory effect on certain enzyme expression. The expression recombinant vector contains a promoter free from manifesting inhibition due to an inorganic sulfur compound or a sulfur-containing amino acid. The recombinant microorganism also contains a gene for desulfurizing the sulfur-containing heterocyclic compound. 

Kelly DP, ShergiU, JK, Wood AP. 1997. Oxidative metabolism of inorganic sulfur compounds by bacteria. Antonie Leeuwenhoek 71 95-107. 

I. Inorganic sulfur compounds containing another (usually more electropositive) element. When the other element is an alkali or alkaline earth, the sulfide is ionic in character. Metal sulfides often have unusual stoichiometries. Examples of sulfides include H2S, Na2S, FeS, and HgS. 2. Organic sulfides are also referred to as thioethers and have the general structure R—S—R. Biochemical examples of sulfides include methionine, cystathionine, and djenkolic acid. If the two R groups are identical, the substance can be referred to as a symmetrical sulfide (biological examples of which are lanthionine and homo-lanthionine). 

In the chain from soils to plants to humans, inorganic sulfur, or more accurately, the sulfate ion (SO42-), is taken up by plants and converted within the plant to organic compounds (the sulfur amino acids). These amino acids combine with other amino acids to make up plant protein. When the plant is eaten by a human or by livestock animals, die protein is broken down and die amino acids are absorbed from the digestive tract and recombined 111 the proteins of the animal body. The most important feature of sulfur in die food chain is that plants use inorganic sulfur compounds to make sulfur amino acids, whereas animals and humans use the sulfur amino acids for their own processes and excrete inorganic sulfur compounds resulting from the metabolism of the sulfur amino acids. 

Sulfur in Inorganic Chemistry , Vol 2, Dekker, NY (1972), 145 ( The Pharmacology and Toxicology of Inorganic Sulfur Compounds by B. Soibo) 30) G.V. Kuznetsov et al, Reasons for the Spontaneous Explosions of Charges of Ammonium Nitrate Explosives in Sulfide Ores , GornZh(Russ) 147, 71—74... 

As our understanding of the way reduced sulfur compounds function in the marine ecosystem has grown so has the need for methods which allow for the sampling and preservation of complex mixtures of organic and inorganic sulfur compounds in the field and their subsequent separation and analysts at a later time. 

Early studies of reduced sulfur in the environment centered on the role of sulfate reducing bacteria in sediments and the measurement of hydrogen sulfide and other simple inorganic sulfur compounds in pore waters. Simple colorimetric assays are probably still the best for such studies. Typical methods include the methylene blue determination of sulfide (26.27) and the dithio-nitrobenzoic acid (DTNB) method for total thiols (28.29). 

By the disproportionation of these inorganic sulfur compounds the organism is able to conserve energy for growth. 

Table 11.4 Inorganic Sulfur Compounds Compound Name and Formula Properties... 

A large number of inorganic sulfur compounds, including halides and salts, are widely used in industry. The more important of these are listed in Table 11.4. 

In addition to the miscellaneous inorganic sulfur compounds listed in Table 11.4, four sulfur compounds were discussed separately for their toxicities. Of these, which is the most toxic What is its mode of toxicity ... 

Schaefer, B. A. Analysis of inorganic sulfur compounds by flame ionisations detector. Anal. Chem. 42, 448 (1970). 

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