Development of Instrumental Methods of Analysis of Sulfur Compounds in Coal Process Streams. Final Technical Report, September 30, 1977-September 29, 1981

摘要

The general objective was resource development in the analytical chemistry of sulfur compounds for the evolving new coal technologies. Based on fundamental considerations, judiciously selected methods of instrumental analysis were developed for determining sulfur compounds in coal conversion process streams. Significant sulfur moieties were identified with the aid of thermodynamic criteria, taking into account the blocking of some equilibria by sluggish kinetics. Two discrete types of procedures were developed for selected moieties, viz., (1) enthalpimetric methods, which rely on measurements of heats of reaction in adiabatic cells; (2) voltammetric methods, using glassy carbon indicator electrodes. Stability domains of thirty-six (36) inorganic sulfur compounds were mapped as function of redox potential and pH. Based on this information, the occurrence probability of specified sulfur contaminants in coal conversion streams was assessed. In developing quantitative analytical methods, specificity was optimized by choice of selective reagents for calorimetric determinations, and by using controlled potential scans and intrinsically selective techniques (such as differential pulse measurements) in voltammetry. Sensitivity was maximized by reliance upon appreciably exothermic reactions on the one hand, and the use of rotated disk electrodes on the other hand. Precision, accuracy and interferences were assessed in a variety of coal gasification and liquefaction process stream samples. (ERA citation 07:006680)