FREMGANGSM}TE FOR OMDANNING AV ETAN

摘要

Fluidized beds of iron in alpha-alumina solid solution catalysts useful in converting feed gas mixtures of ethane, oxygen and hydrogen chloride to vinyl chloride and ethylene are maintained at peak efficiency by onstream addition of one or more of the catalyst precursor materials such as an iron compound and alpha-alumina particles. Iron lost by the catalyst is replaced by onstream addition of an iron compound to regenerate the catalyst. Overhead losses of catalyst as fines formed by attrition are replaced by on-stream addition of alphaalumina particles which are converted to catalyst particles by the simultaneous or subsequent addition of the catalyst metal precursor compounds. The presence of an atmosphere of the feed gases appears to lower the threshold temperature at which iron cations dissolve or diffuse into the alphaalumina host lattice replacing the alumina cations of the host lattice. To form solid solutions of this type in an oxygen atmosphere require extended calcination of 1100.degree. to 1300.degree.C but form easily at temparatures of 500 to 650.degree.C in an atmosphere of the feed gases.