Sulfur scavenging

Treat with sulfur scavenger/sulfur neutralizer. 

Thermolyses of l,3-dichalcogenole-2-thiones and -2-selenones lead formally to carbenes by loss of elemental sulfur and selenium, respectively. These species dimerize to produce 1,4,5,8-tetrachalcogenafulvalenes (Scheme 6). In practice this transformation is carried out in the presence of a sulfur scavenger such as a phosphite or phosphine. Examples of this transformation are compiled in Table 14. 

Uses Sulfur scavenger in lubricants improves antiwear and antifriction props. color/processing stabilizer for polymers ... 

Storage Moisture-sensitive store in cool, dry place keep tightly closed Uses Heat stabilizer for polymers, polyester fibers, PVC, PP antioxidant, friction reducer, sulfur scavenger in lubricants Features Used with metal stabilizers Manuf./Distrib. Aldrich http //www.sigma-aidrich.com, Aldrich http //www.sigma-aidrich.com... 

The catalytic oxidation of sulfur compounds in gas streams is the basis for numerous gas purification proce,s.ses, most of which are covered in other sections of this book. The oxidation of SO2 to SOj as part of a sulfur dioxide removal process is discussed in Chapter 7. The oxidation of HiS to elemental sulfur by the Claus process and related technologies is covered in Chapter 8. The liquid-phase oxidation of H2S to elemental sulfur is described in Chapter 9, and the oxidation of H S and other sulfur compounds in dry boxes and in other sulfur scavenging processes is included in Chapter 16. An area of technology that is not covered... 

Sulfur scavenging processes are typically batch operations. They make use of materials that capture and retain sulfur compounds, but have a finite effective capacity. When this capacity is reached, the spent sorbent (liquid or solid) must be removed and replaced with fresh material. The spent sorbent is normally disposed of as waste, and the production of an environmentally acceptable waste has become a key factor in the selection of. scavenging proces.ses for specific applications. Other important considerations are operating safety and reliability (unattended operation is often required) and, of course, capital and operating costs. 

Sulfur scavenging processes can generally be categorized as follows ... 

Solutions of alkylamitte/aldehyde condensation products have been used in several sulfur-scavenging processes. The spent solution is fiee of sulfur particles, and no nitrogen oxide gases are formed however, it has a very obnoxious odor. It is reported to have corrosion-inhibition properties and to be approved for Gass I, non-hazardous, deep-well disposal (Houghton and Bucklin, 1994). Examples of processes in this category are Gas Treat 114. Gas Treat 113. and Gas Treat... 

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