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Oxidations of sulfur

Utility systems as sources of waste. The principal sources of utility waste are associated with hot utilities (including cogeneration systems) and cold utilities. Furnaces, steam boilers, gas turbines, and diesel engines all produce waste from products of combustion. The principal problem here is the emission of carbon dioxide, oxides of sulfur and nitrogen, and particulates (metal oxides, unbumt... [Pg.290]

The electrolytic processes for commercial production of hydrogen peroxide are based on (/) the oxidation of sulfuric acid or sulfates to peroxydisulfuric acid [13445-49-3] (peroxydisulfates) with the formation of hydrogen and (2) the double hydrolysis of the peroxydisulfuric acid (peroxydisulfates) to Caro s acid and then hydrogen peroxide. To avoid electrolysis of water, smooth platinum electrodes are used because of the high oxygen overvoltage. The overall reaction is... [Pg.477]

S-oxidation of sulfur-containing pesticides such as aldicarb, parathion, and malathion can be of importance in the absence of microbial activity (29). The products of chemical vs biological oxidation are generally identical (eq. 8). [Pg.219]

Numerous oxides of sulfur have been reported and those that have been characterized are SO [13827-32-2] S2O [20901 -21 -7] S O (n = 6-10), SO2, SO, and SO4 [12772-98-4]. Among these, SO2 and SO ate of principal importance. Sulfur oxide chemistry has been reviewed (210—212). Sulfur trioxide, SO, is discussed elsewhere (see Sulfuric acid and sulfur trioxide). [Pg.143]

Oxidation of sulfur dioxide in aqueous solution, as in clouds, can be catalyzed synergistically by iron and manganese (225). Ammonia can be used to scmb sulfur dioxide from gas streams in the presence of air. The product is largely ammonium sulfate formed by oxidation in the absence of any catalyst (226). The oxidation of SO2 catalyzed by nitrogen oxides was important in the eady processes for manufacture of sulfuric acid (qv). Sulfur dioxide reacts with chlorine or bromine forming sulfuryl chloride or bromide [507-16 ]. [Pg.144]

The anaerobic reaction of sulfur dioxide with aqueous ammonia produces a solution of ammonium sulfite [10192-30-0]. This reaction proceeds efficientiy, even with a gas stream containing as Httie as 1 wt % sulfur dioxide. The sulfur dioxide can be regenerated at a high concentration by acidulation or by stream stripping of the ammonium sulfite solution, or the sulfite can be made to precipitate and the ammonia recovered by addition of lime (243). The process can also be modified to produce ammonium sulfate for use as fertili2er (244) (see Fertilizers). In a variant of this process, the use of electron-beam radiation cataly2es the oxidation of sulfur dioxide in the presence of ammonia to form ammonium sulfate (245). [Pg.144]

Solutions of iron chelates can be used to remove hydrogen sulfide and oxides of sulfur and nitrogen in industrial gas scmbbing processes (41,50,51) before flue gases are released to the atmosphere. [Pg.394]

Oxides of sulfur-containing azoles comprise another class of non-aromatic azoles. [Pg.77]

The problems with the combustion reaction occur because the process also produces many other products, most of which are termed air pollutants. These can be carbon monoxide, carbon dioxide, oxides of sulfur, oxides of nitrogen, smoke, fly ash, metals, metal oxides, metal salts, aldehydes, ketones, acids, polynuclear hydrocarbons, and many others. Only in the past few decades have combustion engineers become concerned about... [Pg.78]

The most widely used pulping process is the kraft process, as shown in Fig. 6-11, which results in recovery and regeneration of the chemicals. This occurs in the recovery furnace, which operates with both oxidizing and reducing zones. Emissions from such recovery furnaces include particulate matter, very odorous reduced sulfur compounds, and oxides of sulfur. If extensive and expensive control is not exercised over the kraft pulp process, the odors and aerosol emissions will affect a wide area. Odor complaints have been reported over 100 km away from these plants. A properly controlled and operated kraft plant will handle huge amounts of material and produce millions of kilograms of finished products per day, with little or no complaint regarding odor or particulate emissions. [Pg.90]

The principal components of atmospheric chemical processes are hydrocarbons, oxides of nitrogen, oxides of sulfur, oxygenated hydrocarbons, ozone, and free radical intermediates. Solar radiation plays a crucial role in the generation of free radicals, whereas water vapor and temperature can influence particular chemical pathways. Table 12-4 lists a few of the components of each of these classes. Although more extensive tabulations may be found in "Atmospheric Chemical Compounds" (8), those listed in... [Pg.169]

Oxides of sulfur Sulfur dioxide SO2 Sulfur trioxide SO3 Sulfuric acid H2SO4 Ammonium bisulfate (NH))HS04 Ammonium sulfate (NH4)2S04... [Pg.171]

Oxides of sulfur react with copper oxide to form copper sulfate. Removal with a dry particulate control system follows. [Pg.485]

Why are "oxides of nitrogen" and "oxides of sulfur" usually reported in emission inventory tables rather than the actual oxidation states ... [Pg.488]

Sulfur oxides (SO,) are compounds of sulfur and oxygen molecules. Sulfur dioxide (SO2) is the predominant form found in the lower atmosphere. It is a colorless gas that can be detected by taste and smell in the range of 1, (X)0 to 3,000 uglm. At concentrations of 10,000 uglm , it has a pungent, unpleasant odor. Sulfur dioxide dissolves readily in water present in the atmosphere to form sulfurous acid (H SOj). About 30% of the sulfur dioxide in the atmosphere is converted to sulfate aerosol (acid aerosol), which is removed through wet or dry deposition processes. Sulfur trioxide (SO3), another oxide of sulfur, is either emitted directly into the atmosphere or produced from sulfur dioxide and is readily converted to sulfuric acid (H2SO4). [Pg.38]

Fire Hazards - Flash Point Not flammable Flammable Limits in Air (%) Not flammable Fire Extinguishing AgerUs Not pertinent Fire Extinguishing Agents Not To Be Used Not pertinent Special Hazards of Combustion Products Oxides of sulfur and phosphorous may be formed when exposed to a fire situation Behavior in Fire Data not available Ignition Temperature Not pertinent Electrical Hazard Not pertinent Bunting Rate Not pertinent. [Pg.33]

Used Not pertinent Special Hazards of Combustion Products Irritating oxides of sulfur may be formed Behavior in Fire Not pertinent Ignition Temperature No data Electrical Hazard Not pertinent Burning Rate Not pertinent. [Pg.369]

Vanadium pentoxide, VjOj, is used as a eatalyst in the oxidation of sulfur dioxide. The meehanism involves oxidation-reduetion of V2O5 that exists on the support at operating eonditions in the molten state. The meehanism of reaetion is ... [Pg.6]

The gases normally monirored include oxides of sulfur and nitrogen (SO, NO ),... [Pg.1314]


See other pages where Oxidations of sulfur is mentioned: [Pg.275]    [Pg.299]    [Pg.7]    [Pg.144]    [Pg.174]    [Pg.198]    [Pg.213]    [Pg.421]    [Pg.161]    [Pg.203]    [Pg.398]    [Pg.224]    [Pg.530]    [Pg.2095]    [Pg.76]    [Pg.82]    [Pg.168]    [Pg.176]    [Pg.282]    [Pg.495]    [Pg.526]    [Pg.306]    [Pg.361]    [Pg.402]    [Pg.1264]    [Pg.250]    [Pg.662]    [Pg.695]    [Pg.695]    [Pg.695]   
See also in sourсe #XX -- [ Pg.218 ]




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Anodic Oxidation of Sulfur Compounds

Catalyzed oxidation of sulfur dioxide

Flue Gases Containing Oxides of Sulfur

Nitric Oxide Complexes of Iron-Sulfur Proteins

OXIDATION OF SULFUR COMPOUNDS OTHER THAN SO

Oxidation Mechanisms of Cysteine Sulfur

Oxidation Mechanisms of Methionine Sulfur

Oxidation of Cysteine Sulfur in Vivo

Oxidation of Cystine Sulfur

Oxidation of Hydrogen Sulfide and Free Sulfur

Oxidation of Methionine Sulfur in Vivo

Oxidation of Organo-sulfur Compounds

Oxidation of Sulfide and Elemental Sulfur

Oxidation of Sulfur Atoms the MacDonald-Fischer Degradation

Oxidation of Sulfur Compounds

Oxidation of Thiols and Other Sulfur Compounds

Oxidation of dissolved sulfur dioxide

Oxidation of elemental sulfur

Oxidation of reduced sulfur compounds

Oxidation of sulfur dioxide

Oxidation of sulfur groups

Oxidation of sulfur-containing compounds

Oxidation of sulfurous acid

Oxidation state of sulfur

Oxidation with Peroxo Acids of Sulfur

Oxidation, of reduced sulfur

Oxidation-Reduction of Sulfur

Oxidation-reduction reactions of iron-sulfur clusters

Oxidations of alcohols based on sulfur reagents

Oxidative Imination of Sulfur Compounds

Oxidative halogenation of sulfur compounds sulfonyl chlorides

Oxidative mechanisms of sulfur fuels

Oxides and oxoacids of sulfur

Oxides of Sulfur, Selenium, and Tellurium

Oxides of sulfur

Oxides of sulfur

Oxides, Oxyacids, and Oxyanions of Sulfur

Photochemical oxidation of sulfur

Photochemical oxidation of sulfur dioxide

Pyrolusite, in oxidation of sulfurous

Pyrolusite, in oxidation of sulfurous acid to dithionate ion

Reaction of alkene oxides (oxiranes) with sulfur compounds

Selective Oxidation of H2S Over SiC-Supported Iron Catalysts into Elemental Sulfur

Sulfur dioxide oxidation accuracy of models

Sulfur oxide

Sulfur oxides oxidation

Sulfur oxidized

Sulfur oxidizer

Sulfur trioxide activator, DMSO oxidation of alcohols

Sulfurous oxide

The Oxidation of Sulfur

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