Sulfur dioxide potential oxidants

Minor and potential new uses for ammonium thiosulfate include flue-gas desulfurization (76,77), removal of nitrogen oxides and sulfur dioxide from flue gases (78,79), converting sulfur ia hydrocarbons to a water-soluble form (80), and converting cellulose to hydrocarbons (81,82) (see Sulfur REMOVAL AND RECOVERY). 

Hot surfaces and electric sparks are potential ignition sources for carbon disulfide. The ignition temperature depends on specific conditions, and values from 90 to 120°C in air have been reported (2,22). Data on carbon disulfide oxidation and combustion have been summarized (18). Oxidation products ate generally sulfur dioxide [7446-09-5] and carbon dioxide [124-58-9J ... 

There are several potential sources of error in these methods. The filters routinely used have a relatively high and somewhat variable sulfate content, so that, at concentrations lower than 10 Mg/m and sampling periods less than 24 h, the reliability of tlie sulfate measurement is reduc. Several different types of filtering media adsorb sulfur dioxide during the ftrst few hours of sampling this alters the amount of sulfate observed. This interference can become critical when sampling periods are less than 24 h and the concentration ratio of sulfur dioxide to sulfate is greater than 5 1. Interference can also be introduced by hot-water extraction when reduced sulfur compounds like sulfite are present, because they are oxidized to sulfates in this process. Another possible error source is that some of the various analytic procedures us for sulfate determination may be influenced by other substances also present in the particulate matter. 

The use of excess formic acid to destroy excess nitric acid (5M) in nuclear fuel reprocessing waste solutions at 100°C is potentially hazardous because of an induction period, high exothermicity and the evolution of large amounts of gas, mainly carbon dioxide, dinitrogen oxide and nitrogen oxide, with some nitrogen and dini-trogen tetraoxide. The system has been studied thermokinetically, and the effects of various salts (which decrease the reaction rate) and sulfuric acid (which increases the rate) were determined [1],... 

We recognized at least two potential difficulties with this oxidative degradation procedure (1) Mass transfer can serve to broaden the observed sulfur dioxide evolution as compared with the undiluted coal. (2) At the low flow rates utilized, variation in the exit flow rate as the degradation proceeds could cause a broad sulfur dioxide evolution to appear as peaks. Results of the two experiments described below indicate to our satisfaction that these potential problems, if present, do not interfere with our interpretation. 

The factors that influence corrosion of steels in soils are the type of soil moisture content and the position of the water table soil resistivity and soluble ion content soil pH oxidation-reduction potential and the role of microbes present in soil. The exposure of a buried pipe to the soil environment is illustrated in Figure 4.2. The steel pipe is exposed to both meteoric water passing through ground surface and the water in the ground. The meteoric water may be acidic due to the presence of carbon dioxide and sulfur dioxide in the atmosphere. The soil water may be acidic in addition to some dissolved minerals. The steel pipe is partially above the water table with the rest below the water. The pH and the dissolved ions in the ground water provide a corrosive environment. 

Since the mid-1970 s, increasing interest has emerged in the environmental consequences of the large scale deposition of atmospheric contaminants. The deposition of acid-forming constituents, sulfate and nitrate, is of particular concern for potentially adverse ecological effects. These species derive from the oxidation of sulfur dioxide (SO ) and nitrogen oxides (NO and NO ). Over most if... 

Other pollutants in Diesel exhaust, besides carbon monoxide, are primarily aldehydes (OCHR), sulfur dioxide (SO2), nitrous oxides (NOx, max. 0.1%), and hydrocarbons (C xHy). The smell or stench for which Diesel engines are notorious is caused by trace amounts of certain hydrocarbons and aldehydes which the most modem analytical instruments can barely identify, let alone measure. The sensitivity of the human nose to these compounds is, however, extremely high and out of all proportion to the actual quantities present. Some of the hydrocarbons are considered carcinogenic and thus represent a potential long-term hazard, but they are irrelevant to our study. 

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