Complex sulfur oxides

Silver Thiosulfate. Silver thiosulfate [23149-52-2], Ag 2 y is an insoluble precipitate formed when a soluble thiosulfate reacts with an excess of silver nitrate. In order to minimize the formation of silver sulfide, the silver ion can be complexed by haUdes before the addition of the thiosulfate solution. In the presence of excess thiosulfate, the very soluble Ag2(S203) 3 and Ag2(S203) 3 complexes form. These soluble thiosulfate complexes, which are very stable, are the basis of photographic fixers. Silver thiosulfate complexes are oxidized to form silver sulfide, sulfate, and elemental sulfur (see Thiosulfates). 

Compounds considered carcinogenic that may be present in air emissions include benzene, butadiene, 1,2-dichloroethane, and vinyl chloride. A typical naphtha cracker at a petrochemical complex may release annually about 2,500 metric tons of alkenes, such as propylenes and ethylene, in producing 500,000 metric tons of ethylene. Boilers, process heaters, flares, and other process equipment (which in some cases may include catalyst regenerators) are responsible for the emission of PM (particulate matter), carbon monoxide, nitrogen oxides (200 tpy), based on 500,000 tpy of ethylene capacity, and sulfur oxides (600 tpy). 

Reactions with sulfides, polysulfides, sulfur oxides and the oxoacids of sulfur are complex and the products depend markedly on reaction conditions (see also p. 745 for blue crystals in chamber acid). Some examples are ... 

The sulfur-rich oxides S 0 and S 02 belong to the group of so-called lower oxides of sulfur named after the low oxidation state of the sulfur atom(s) compared to the best known oxide SO2 in which the sulfur is in the oxidation state +4. Sulfur monoxide SO is also a member of this class but is not subject of this review. The blue-green material of composition S2O3 described in the older literature has long been shown to be a mixture of salts with the cations S4 and Ss and polysulfate anions rather than a sulfur oxide [1,2]. Reliable reviews on the complex chemistry of the lower sulfur oxides have been published before [1, 3-6]. The present review deals with those sulfur oxides which contain at least one sulfur-sulfur bond and not more than two oxygen atoms. These species are important intermediates in a number of redox reactions of elemental sulfur and other sulfur compounds. 

A biosorption method for the separation of sulfur compounds from fossil fuels, by using a sulfur-biosorption agent and followed by the oxidation of the biosorbed complex. The oxidation is carried out in an aqueous phase containing an effective amount of oxygen and, optionally a biocatalyst, in which case an incubating stage is incorporated for the reaction to take place. 

Vlcek and Vlcek149 have summarized the reactivity of dithiolenes in a general way. The n-delo-calization in the dithiolenes favors an extensive redox series but restricts axial interactions. Reaction in this position can only occur if the incoming ligand can incorporate its own 7t-orbitals into that of the planar complex. The dianions are nucleophilic at sulfur oxidation to the anion or neutral species lets them become electrophilic and Diels-Alder-type additions may occur. 

The kinetics of chromium(l 11 )-catalyscd oxidation of fonnic acid by Ce(TV) in aqueous H2SO4 can be rationalized in terms of initial formation of an outer-sphere complex involving oxidant, catalyst, and substrate (S), Ce(TV)(S)Cr(III), followed by an inner-sphere complex Ce(III)(S)Cr(IV). It is proposed that electron transfer occurs within this complex from substrate to Cr(TV) (with elimination of H+) followed by fast reaction to give CO2 (again with elimination of H+).54 In contrast, there was no kinetic evidence for the accumulation of a corresponding inner-sphere intermediate in the osmium(VIII)-catalysed Ce(TV) oxidation of DMSO to dimethyl sulfone here, the observed rate law was rationalized in terms of rate-determining bimolecular electron transfer from DMSO to Os(VHI) in an outer-sphere step.55 The kinetics of oxidation of 2-hydroxy-l-naphthalidene anil by cerium(IV) in aqueous sulfuric acid have been... 

In order to mimic the attack of ZDDP onto the oxide surface (FeO), the structure of the possible complexes formed between an O2 ion and ZDDP was examined. The oxide anion was allowed to interact with the positively charged atoms (zinc and phosphorus), and partially negatively charged sulfur atoms of the additive molecule. The heats of complex formation (Oxide ion + ZDDP -ZDDP Oxide) and total energies determined for each complex were reported (Armstrong et al., 1998). 

Szacilowski K, Chmura A, Stasicka Z. Interplay between iron complexes, nitric oxide and sulfur ligands Structure, (photo)reactivity and biological importance. Coord Chem Rev 2005 249 2408-36. 

Identification of the microorganisms found in both the process water and on the metal surface. Tests for nitrite-utilizing bacteria or sulfur oxidizers are more complex. (Stott)5... 

In 1942, soon after demobilization from the army, he had defended his PhD thesis on the theme, Oxidation of Hydrogen Sulphide . He generalized this research in the book Intermediate Products of Complex Reactions in Gaseous Phase (Moscow-Leningrad, Publishing house AS USSR, 1946) where, for the first time, it has been shown that such intermediate products as sulfur oxide possess properties of free radicals and can propagate oxidation. It was an important scientific benchmark. 

Lanthanides as components in complex oxide systems In perovskites For conduction in electrocatalysis For oxidizing properties For hydrogenation properties For synthetic gas (CO-H2) reactions To provide sulfur oxides (SO, ) control In oxysulphides In other systems ... 

Coordination OrganometalUc Chemistry Principles Electron Transfer Reactions Theory Macrocyclic Ligands Metal Ion Toxicity Oxides Solid-state Chemistry Polynuclear Organometallic Cluster Complexes Sulfur Organic Polysulfanes Thallium Organometallic Chemistry. 

The photooxidation of CS2 and COS has also been examined in flash photolysis studies. The spectra of a number of sulfur oxides have been detected. Both SO2 and SO have been definitely identified A system of absorption bands appearing between 2500 and 2400 A. have been assigned to the sulfur monoxide molecule, S2O, on the basis of mass spectrometric evidence. A transient spectrum observed in the wavelength region, 1840-1740 A., has been tentatively assigned to a short-lived isomeric form of sulfur dioxide, the structure of which may be SOO, sulfur superoxide. The probable precursor of all these species is the sulfur monoxide which arises from the reaction of atomic sulfur with O2. The overall reaction is complex a number of possible steps have been postulated to account for the intermediates, SO and SOO, as well as for the final products S2O and SO2. With triplet sulfur atom, the most likely reaction to produce SO is S( P) -H Ojf S,-) S0(32 ) -I- 0(V) (43)... 

ON2S3, Nitrogen sulfur oxide, 25 52 ONjSijCjHi, Urea, N,N -dimethyl-A/,N -bis(trimethylsylyl)-, 24 120 OPCijHis, Phosphine, triphenyl-, oxide cerium complexes, 23 178 OPC His, Benzaldehyde, 2-(diphenylphos-phino)-, 21 176... 

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