Abstract: A process for preparing 2,6-dimethylphenol from 2,4,6-trimethylphenol is provided. The process includes two steps: (1) selective oxidation of 2,4,6-trimethylphenol to 3,5-dimethyl-4-hydroxybenzaldehyde and (2) deformylation of the resulting benzaldehyde to 2,6-dimethylphenol. In step (1), the 2,4,6-trimethylphenol is reacted with oxygen-containing gases at temperatures of 20 to 200° C. in the presence of an iron-containing catalyst, which has higher 3,5-dimethyl-4-hydroxybenzaldehyde selectivity than the known copper-based catalysts. In step (2), a copper-containing catalyst is used to replace the customarily used precious metal catalysts for the effective deformylation of the 3,5-dimethyl-4-hydroxybenzaldehyde to 2,6-dimethylphenol.

Abstract: A method for selectively oxidizing hydrogen sulfide to elemental sulfur is disclosed. The method is performed at a temperature ranged from 50 to 400° C. and at a pressure ranged from 0.1 to 50 atm. The elemental sulfur can be effectively recovered from a gas mixture containing hydrogen sulfide in the presence of a catalyst. The catalyst includes a vanadium-containing material and a catalytic substance selected from the group consisting of scandium (Sc), yttrium (Y), lanthanum (La), samarium (Sm) and compounds thereof. In another embodiment, this catalyst further includes an antimony-containing promoter (antimony compounds) which further exhibit a more effective catalytic performance.

Abstract: A method for selectively oxidizing hydrogen sulfide to elemental sulfur is disclosed. The elemental sulfur can be effectively recovered from a gas mixture containing hydrogen sulfide in the presence of a multi-component catalyst. The multi-component catalyst includes an antimony-containing substance and a vanadium-and-magnesium-containing material. The antimony containing substance may be antimonous oxide (Sb2O3) or antimony tetraoxide (&agr;-Sb2O4), and the vanadium and magnesium containing material may be magnesium pyrovanadate (Mg3V2O8) or Mg2V2O7.

Abstract: The present invention discloses a method of selectively oxidizing hydrogen sulfide to elemental sulfur, in which a H.sub.2 S-containing gas mixture contacts with an oxygen-containing gas at about 50-400.degree. C. in the presence of an mixed-oxide catalyst. The reaction product mixture contains substantially no sulfur dioxide. The mixed-oxide catalyst, in addition to iron (III) and molybdate (VI) components, further contains a antimony component as a promoter.

Abstract: The present invention discloses a method of selectively oxidizing hydrogen sulfide to elemental sulfur, in which a H.sub.2 S-containing gas mixture contacts with an oxygen-containing gas at 50.degree.-500.degree. C. in the presence of an iron-based catalyst. The reaction product mixture contains substantially no sulfur dioxide. The iron-based catalyst, in addition to iron atom, further contains a promoter of cerium, tin or antimony.

Abstract: The present invention discloses a method of selectively oxidizing hydrogen sulfide to elemental sulfur, in which a H.sub.2 S-containing gas mixture contacts with an oxygen-containing gas at 50.degree.-500.degree. C. in the presence of a mixed-metal catalyst. The reaction product mixture contains substantially no sulfur dioxide. The mixed-metal catalyst contains vanadium atom and molybdenum atom or magnesium atom.

Abstract: The present invention discloses a method of selectively oxidizing hydrogen sulfide to elemental sulfur, in which a H.sub.2 S-containing gas mixture contacts with an oxygen-containing gas at 50.degree.-500.degree. C. in the presence of a bismuth-based catalyst. The reaction product mixture contains substantially no sulfur dioxide. The bismuth-based catalyst may further contain molybdenum or vanadium atom.