Sulfide modifier

Reber JF, Rusek M (1986) Photochemical hydrogen production with platinized suspensions of cadmium sulfide and cadmium zinc sulfide modified by silver sulfide. J Phys Chem 90 824-834... 

The application of grazing angle reflectance spectroscopic techniques (GRAS) to high polymer adsoiption has not been as extensive as in the area of self-assembled monolayers. However, the adsoiption of ethylene sulfide modified polystyrene on gold surfaces from toluene was demonstrated by GRAS of dried surfaces (120). 

Recent study found that Pd sulfide prepared by sulfiding PdCU (structure detennined with XRD was Pd S ) yielded methanol with a selectivity above 95-mol% (70). This result is notable because, so far, only Mo and W sulfides have been known to show weak activities for the synthesis of gaseous hydrocarbons from syngas (77). This type of sulfides had some attentions because Mo sulfide modified with alkali metal additives showed a constant activity for alcohol synthesis even in die presence of H2S (77). This is in marked contrast with the... 

Figure 1. Formation rate of products with the supported Pd sulfides modified with or without additives in comparison with the bulk sulfide (P/dS ).

The effect of the additives was then investigated in more detail. Figure 2 shows the formation rate of products widi the sulfided Ca/Pd/SiOa with different atomic ratios of Ca to Pd at different reaction temperatures (613 K (a) mid 573 K (b)). The reaction pressure and gas-hourly space velocity were 5.1 MPa and 20 m (STP) kg-caf h, respectively. At 613 K, methanol fonnation rate increases sharply with the atomic ratios of Ca to Pd up to 0.5, and shows a plateau above this ratio. The formation rates of methane and CO2, on the other hand, show the maximum at Ca/Pd=0.5. At this ratio, the rate enhancement for methanol formation (4.5) was higher than that for methane formation (3.5). Thus, Ca additive could promote the formation of methanol rather than methane. It should also be noted here that sulfided Ca/SiO2 showed no activity for CO hydrogenation. At the lower reaction temperature, the rate enhancements for methanol and mediane formations were 5.5 and 2.5, respectively (Ca/Pd=0.5). The promoting effect of Ca additives on methanol formation was more notable at the lower reaction temperature. Similar results were obtained with supported sulfides modified with Mg and/or Y additives, whereas Cs and Mn additives hardly affected methanol formation irrespective of their contents. 

Hack, H. P., Galvanic Corrosion of Piping and Fitting Alloys in Sulfide-Modified Seawater, DTNSRDC/SME-79-31, May, 1979. 

Metals Metal halides Metal oxides Metal sulfides Modifies zeolites Model gasoline (400 ppm S) Among several types of adsorbents explored, Ni-based adsorbents exhibited better performance for removing sulfur compounds. 

The ethylene-sulfide-modified material gave a sulfur-containing derivative that had excellent capture kinetics for removing mercury, cadmium, and lead from... 

Figure 18 Removal of Hg, Cd, and Pb by the ethylene sulfide-modified resin at a flow rate of 1.5 L/min through 27-cm column containing 50 g of resin.

The dithiocarbamate-type ligand produced from the reaction of carbon disulfide with silica-polyamine composites represents a viable alternative to the previously reported ethylene-sulfide-modified composites. This material should prove useful for immobilizing mercury that is contained in aqueous waste streams. The resin is not going to be useful for applications requiring the regeneration and reuse of the resin. There are several other polystyrene and silica-based mercury removal resins available on the market, and it remains to be shown how these resins compare with WP-3. 

In the treatment of sour wells (wells produdng H S gas), the possibility of iron sulfide (FeS) precipitation exists. FeS precipitates at a pH of about 2, which poses a potential problem as acid spends and pH rises. Hall and Dill have shown that a mixture of nitrilotriacetic add (NTA), mutual solvent (EGMBE), and a sulfide modifier can control the precipitation of EeS. Sulfide modifier additives are available from service companies and may be included in the iron control additive package. 

It has been shown that there is significant partial charge transfer between anions and the electrode surface upon adsorption. Therefore, there has been some ambiguity as to whether such an adsorbed layer should be thought of as an anion monolayer (e.g., a halide-modified or sulfide-modified electrode) or a monolayer of a neutral species (e.g., a halogen-modified or sulfur-modified electrode), given that the true state of the surface species is somewhere in between these two. To... 

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