Hydrogen sulfide determination

EPA. 1976. Effect of hydrogen sulfide on fish and invertebrates, Part II—Hydrogen sulfide determination and relationship between pH and sulfide toxicity. Report to the U.S. Environmental Protection Agency, Environmental Research Lab, Duluth, MN, by Broderius SJ, Smith LL Jr., University of Minnesota, Department of Entomology, Fisheries, and Wildlife, St. Paul, MN. 

This reaction will allow the solution of less than 1 pg/liter of iron assuming that 82 is the only sulfide species. Waters of this type have low iron contents and low sulfate levels, and they often contain traces of hydrogen sulfide. The analysis for this type of water shown in Table 7-6 shows only slightly more iron than predicted. Unfortunately, no hydrogen sulfide determination was made. 

Carbonate is measured by evolution of carbon dioxide on treating the sample with sulfuric acid. The gas train should iaclude a silver acetate absorber to remove hydrogen sulfide, a magnesium perchlorate drying unit, and a CO2-absorption bulb. Sulfide is determined by distilling hydrogen sulfide from an acidified slurry of the sample iato an ammoniacal cadmium chloride solution, and titrating the precipitated cadmium sulfide iodimetrically. 

Analytical Methods. Detection of carbonyl sulfide ia air can be done by gas chromatography or by combustion to sulfur dioxide and determination of the latter. Where hydrogen sulfide and carbonyl sulfide occur together, the carbonyl sulfide can be determined by combustion after hydrogen sulfide is absorbed by lead acetate, which does not absorb carbonyl sulfide (35). 

Natural gas - Determination of sulfur compounds. Determination of hydrogen sulfide, mercaptan sulfur, and carbonyl sulfide sulfur by potentiometry. Also BS 3156 Subsection 11.4.3 1994 Natural gas - Determination of sulfur compounds. Lmgener combustion method. Also BS 3156 Subsection 11.4.5 1994... 

Other Techniques Continuous methods for monitoring sulfur dioxide include electrochemical cells and infrared techniques. Sulfur trioxide can be measured by FTIR techniques. The main components of the reduced-sulfur compounds emitted, for example, from the pulp and paper industry, are hydrogen sulfide, methyl mercaptane, dimethyl sulfide and dimethyl disulfide. These can be determined separately using FTIR and gas chromatographic techniques. 

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. 

The alkyl chain distribution of the base alcohol in alcohol sulfates is easily determined by gas chromatography. However, alcohol sulfates and alcohol ether sulfates are not volatile and require a previous hydrolysis to yield the free alcohol. The extracted free alcohol can be injected directly [306] or converted to its trimethylsilyl derivative before injection [307]. Alternatively, the alcohol sulfate can be decomposed by hydroiodic acid to yield the alkyl iodides of the starting alcohols [308]. A preferred method forms the alkyl iodides after hydrolysis of the alcohol sulfate which are analyzed after further extraction of the free alcohol, thus avoiding the formation of hydrogen sulfide. This latter method is commonly used to determine the alkyl chain distribution of alcohol ether sulfates. 

The sulfur dioxide reacts with more hydrogen sulfide to give elemental sulfur and water. Write balanced chemical equations for these two reactions, and determine the minimum mass of hydrogen sulfide that a volcano must emit in order to deposit 1.25 kg of sulfiir. 

It is apparent that a new synthetic methodology, preferably catalytic, is needed for the synthesis of this important class of 2-(perfinoroalkyl)ethane thiols. In this context, a variety of catalysts was examined to determine if they wonld catalyze the hydrogenolysis of 2-(perfinorohexyl)ethane thiocyanate. In the conrse of this study, much to our surprise, it was discovered that a carbon supported Pd-Sn would catalyze the reaction. It is known that palladium and other group Vtll metal catalysts are poisoned by the product thiol, traces of hydrogen sulfide byproduct, and the hydrogen cyanide co-prodnct (6), but our observations are that this catalyst is surprisingly robust in the reaction medium. 

Carroll J J. and A.E. Mather, "Phase Equilibrium in the System Water-Hydrogen Sulfide Experimental Determination of the LLV Locus", Can. J. Chem. Eng., 67,468-470 (1989a). 

The work described here was undertaken to determine what happens to the sulfur that is volatilized, and what is the source of the hydrogen sulfide, sulfur dioxide, and sulfate. The products formed by lemons treated with elemental sulfur were employed in radioactive form for the treatment of other lemons. 

In all treated fruit the percentage of sulfur determined as sulfate in peel increased over the controls (Table IV). Of the four different treatments, the sulfate having the highest percentage specific activity was where elemental sulfur was applied. Specific activity was next highest in the hydrogen sulfide and lowest for the sulfur dioxide treatment. 

Analytical Methods for Determining Hydrogen Sulfide in Biological Samples... 

If you are exposed to hydrogen sulfide, many factors determine whether you ll be harmed. These factors include the dose (how much), the duration (how long), and how you come in contact with it. You must also consider the other chemicals you re exposed to and your age, sex, diet, family traits, lifestyle, and state of health. 

IS THERE A MEDICAL TEST TO DETERMINE WHETHER I HAVE BEEN EXPOSED TO HYDROGEN SULFIDE ... 

Additional studies of immune function in animals exposed to hydrogen sulfide by inhalation are needed. A bacterial and/or viral challenge study would be especially useful to determine whether exposure to hydrogen sulfide increases susceptibility to infection. 

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