Hydrogen sulfide properties

The conversion products, other than gas and hydrogen sulfide (H2S), are essentially a gasoline fraction that, after pretreatment, will be converted by catalytic reforming an average quality distillate fraction to be sent to the gas oil pool and an atmospheric residue or vacuum distillate and vacuum residue whose properties and impurity levels (S, N, Conr. 

The process implications of equation 3 go beyond the weU-known properties (27—29) of NMP to faciUtate S Ar processes. The function of the aminocarboxylate is also to help solubilize the sulfur source anhydrous sodium sulfide and anhydrous sodium hydrogen sulfide are virtually insoluble in NMP (26). It also provides a necessary proton acceptor to convert thiophenol intermediates into more nucleophilic thiophenoxides. A block diagram for the Phillips low molecular weight linear PPS process is shown in Eigure 1. 

Physical Properties. Hydrogen sulfide, H2S, is a colorless gas having a characteristic rotten-egg odor. The physical properties of hydrogen sulfide are given in Table 2. 

Table 2. Physical and Thermodynamic Properties of Hydrogen Sulfide...

Chemical Properties. Although hydrogen sulfide is thermodynamically stable, it can dissociate at very high temperatures. The decomposition thermodynamics and kinetics have been reviewed and the equihbrium constant for the reaction has been deterrnined (101,102) ... 

Chemical Properties. Ammonium thiocyanate rearranges upon heating to an equiHbrium mixture with thiourea 30.3 wt % thiourea at 150°C, 25.3 wt % thiourea at 180°C (373,375). At 190—200°C, dry ammonium thiocyanate decomposes to hydrogen sulfide, ammonia, and carbon disulfide, leaving guanidine thiocyanate [56960-89-5] as a residue. Aqueous solutions of ammonium thiocyanate are weakly acidic a 5 wt % solution has a pH of 4—6. 

Chemical Properties. The most significant chemical property of L-ascorbic acid is its reversible oxidation to dehydro-L-ascorbic acid. Dehydro-L-ascorbic acid has been prepared by uv irradiation and by oxidation with air and charcoal, halogens, ferric chloride, hydrogen peroxide, 2,6-dichlorophenolindophenol, neutral potassium permanganate, selenium oxide, and many other compounds. Dehydro-L-ascorbic acid has been reduced to L-ascorbic acid by hydrogen iodide, hydrogen sulfide, 1,4-dithiothreitol (l,4-dimercapto-2,3-butanediol), and the like (33). 

One of the most effective methods of preventing corrosion is the selection of the proper metal or alloy for a particular corrosive service. Once the conditions of service and environment have been determined that the equipment must withstand, there are several materials available commercially that can be selected to perform an effective service in a compatible environment. Some of the major problems arise from popular misconceptions for example, the use of stainless steel. Stainless steel is not stainless and is not the most corrosion-resistant material. Compatibility of material with service environment is therefore essential. For example, in a hydrogen sulfide environment, high-strength alloys (i.e., yield strength above 90,000 psi or Rc 20 to 22) should be avoided. In material selection some factors that are important to consider are material s physical and chemical properties, economics and availability. 

Nesbitt, L. E., et al., Properties of hydrogen sulfide scavengers used in water-based drilling fluids, Proceedings of 36th Annual Technical Meeting of the Petroleum Society, Edmonton, Canada, June 2-5, 1985. 

Fig. 8. Partial molar volumes in the saturated liquid phase of the propane-methane system at IOO°F. (O) (0) Data of B. H. Sage and W. N. Lacey, Some Properties of the Lighter Hydrocarbons, Hydrogen Sulfide, and Carbon Dioxide. American Petroleum...

Chemists use whatever tools they can find in their laboratories to take full advantage of the properties of acids and bases. One tool they use is Kipp s apparatus, a piece of laboratory equipment that relies on acid-base chemistry to do its job. Named for its inventor, Dutch pharmacist Petrus Johannes Kipp (1808-1864), Kipp s apparatus (or gas generator) is especially useful for creating gases, such as carbon dioxide, hydrogen, or hydrogen sulfide, that the chemists can then use in other chemical reactions. 

These experts collectively have knowledge of hydrogen sulfide s physical and chemical properties, toxicokinetics, key health end points, mechanisms of action, human and animal exposure, and quantification of risk to humans. All reviewers were selected in conformity with the conditions for peer review specified in Section 104(I)(13) of the Comprehensive Environmental Response, Compensation, and Liability Act, as amended. 

Information regarding the physical and chemical properties of hydrogen sulfide is located in Table 3-2. 

Physical and Chemical Properties. Information is available on the physical and chemical properties of hydrogen sulfide (ACGIH 1991 Amoore and Hautala 1983 Budavari et al. 1996 HSDB 1998 Leonardos et al. 1969 Lide and Frederikse 1993 NIOSH 1997). However, additional information on those properties that determine the specific fate, transport, and rates of transformation of hydrogen sulfide as part of the larger sulfur cycle would be useful in discerning the environmental fate and behavior of this compound. 

Bhambhani Y, Burnham R, Snydmiller G, et al. 1996b. Effects of 5 ppm hydrogen sulfide inhalation on biochemical properties of skeletal muscle in exercising men and women. Am Ind Hyg Assoc J 57 464-468. 

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