The present invention discloses a process for recovery and regeneration of rare earth metals or salts thereof used as catalyst and which is conveniently integrated within the overall flow sheets of manufacturing dialkyl carbonates. Alkyl carbamate, alcohol and a rare earth metal salt as catalyst selected from the lanthanide series are added in a reactor to afford dialkyl carbonate. The rare earth metal catalyst is selected from samarium, cerium, lanthanum, neodymium, ytterbium, europium and gadolinium. Ammonia is added to a portion of the reaction mixture to precipitate the catalyst and the separated deactivated catalyst is dissolved in acid to afford regenerated catalyst, e.g., in triflic acid in the case of samarium triflate catalyst.

A method and device for separating at least one catalyst from a mixture of homogeneously shaped catalysts, the catalysts comprising at least one metal selected from the group formed by Ni, Co, Mo, W, the catalyst to be separated comprising a characteristic metal selected from the group formed by Ni, Co, Mo, W and the other catalysts of the mixture not containing said characteristic metal, in which method: the grains of the catalyst of said mixture pass in front of the LIBS detection system, the presence of said characteristic metal in the catalysts is detected by the LIBS technique, the wavelength being selected so as to detect said characteristic metal, the LIBS detection system sends a signal to a means for evacuating grains of catalyst to be separated in a manner such as to separate said grains from the other catalysts of said mixture.

The following invention relates to methods for reprocessing SCR catalysts. In a first embodiment, the invention relates to a method for reprocessing SCR catalysts, wherein an oxygen-containing compound of titanium and tungsten or molybdenum is removed from the catalyst and is then reacted with a vanadium compound. In a second embodiment, the invention relates to a method for removing titanium oxide and vanadium, molybdenum, and tungsten compounds from SCR catalysts and to a method for reusing these compounds in such catalysts.

The following invention relates to methods for reprocessing SCR catalysts. In a first embodiment, the invention relates to a method for reprocessing SCR catalysts, wherein an oxygen-containing compound of titanium and tungsten or molybdenum is removed from the catalyst and is then reacted with a vanadium compound. In a second embodiment, the invention relates to a method for removing titanium oxide and vanadium, molybdenum, and tungsten compounds from SCR catalysts and to a method for reusing these compounds in such catalysts.

A carbon monoxide combustion catalyst and a method of making the catalyst used in fluid bed catalytic cracking process. The catalyst can contain metals and other composites which promote oxidation of carbon monoxide to carbon dioxide during regeneration of spent FCC catalyst.

A carbon monoxide combustion catalyst and a method of making the catalyst used in fluid bed catalytic cracking process. The catalyst can contain metals and other composites which promote oxidation of carbon monoxide to carbon dioxide during regeneration of spent FCC catalyst.

Described are methods of dephosphorylation. Methods of dephosphorylation include contacting a phosphate containing substrate with one or more CeO.sub.2 nanocrystal. Also described is modifying the pH of the dephosphorylation reaction to affect the amount and rate of dephosphorylation. Further described are methods of making CeO.sub.2 nanocrystals of the present disclosure.

Described are methods of dephosphorylation. Methods of dephosphorylation include contacting a phosphate containing substrate with one or more CeO.sub.2 nanocrystal. Also described is modifying the pH of the dephosphorylation reaction to affect the amount and rate of dephosphorylation. Further described are methods of making CeO.sub.2 nanocrystals of the present disclosure.

A process is provided for preparing a spent noble metal fixed-bed catalyst for precious metals recovery, comprising: a) adding the catalyst to a caustic solution to wash the spent catalyst and to make a wash slurry having an alkaline pH, wherein the spent catalyst has been in contact with chloroaluminate ionic liquid catalyst, and wherein the spent catalyst comprises from 5 to 35 wt % chloride; and b) filtering the wash slurry and collecting: i) a filter cake having from at least 70 wt % of the chloride in the spent catalyst removed and having the noble metals retained, and ii) a wash filtrate. Also provided is a filter cake comprising a washed consolidated cake having 40 to 75 wt % solids, a cake moisture content from 25 to less than 60 wt %, 0.1 to 1.5 wt % total noble metals, and a residual chloride content of from zero to less than 4 wt %.

A process is provided for preparing a spent noble metal fixed-bed catalyst for precious metals recovery, comprising: a) adding the catalyst to a caustic solution to wash the spent catalyst and to make a wash slurry having an alkaline pH, wherein the spent catalyst has been in contact with chloroaluminate ionic liquid catalyst, and wherein the spent catalyst comprises from 5 to 35 wt % chloride; and b) filtering the wash slurry and collecting: i) a filter cake having from at least 70 wt % of the chloride in the spent catalyst removed and having the noble metals retained, and ii) a wash filtrate. Also provided is a filter cake comprising a washed consolidated cake having 40 to 75 wt % solids, a cake moisture content from 25 to less than 60 wt %, 0.1 to 1.5 wt % total noble metals, and a residual chloride content of from zero to less than 4 wt %.