A process for recovering and regenerating a tungsten compound suitable as co-catalyst in converting carbohydrates with hydrogen into alkylene glycols and polyols, from ash comprising one or more tungsten-oxygen components (e.g. comprising a tungstate and/or tungstic acid). Such ash is obtainable from burning a liquid mixture comprising alkylene glycols and/or polyols and sodium tungstate and/or tungstic acid.

A system and method of producing carbon nanotubes from flare gas and other gaseous carbon-containing sources.

A system and method of producing carbon nanotubes from flare gas and other gaseous carbon-containing sources.

In accordance with one or more embodiments of the present disclosure, a method for regenerating and rejuvenating a spent catalyst comprising coke and contaminant metals includes washing the spent catalyst with a solvent; drying, at least partially, the spent catalyst; partially combusting the spent catalyst to remove a portion of the coke, thereby producing a partially de-coked catalyst; acid washing the partially de-coked catalyst; and fully combusting the partially de-coked catalyst, thereby producing a regenerated and rejuvenated catalyst. The portion of the coke removed during the partial combustion is greater than or equal to 10 wt. % and less than or equal to 60 wt. %. No rare earth elements are added to the partially de-coked catalyst prior to the fully combusting the partially de-coked catalyst.

A flow through decomposition unit has a catalyst between an inlet end and an outlet end. A hydrogen peroxide solution, at 70% by weight hydrogen peroxide or less, is pumped into the inlet end. Steam and oxygen are produced at the outlet end. A system and process provide one or more utilities to a facility, for example a natural gas wellhead separator shed. The decomposition process creates heat, which can be used to heat the facility. The oxygen produced under pressure, and can be used to provide a replacement for other pressurized gasses. Optionally, the system may generate electricity. Optionally, water produced in the process may be used for potable water, process water or to dilute a solution of hydrogen peroxide before it is decomposed. The system includes a hydrogen peroxide tank, a decomposition unit with a catalyst, a heat exchanger, optionally a steam knockout and optionally an electrical generator.

A system and method of producing carbon nanotubes from flare gas and other gaseous carbon-containing sources.

A system and method of producing carbon nanotubes from flare gas and other gaseous carbon-containing sources.

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.

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.

Provided are: a cleaning agent for a denitration catalyst; and a denitration catalyst regeneration method and a denitration catalyst regeneration system which make it possible to efficiently remove matter adhering to a surface of a catalyst and to greatly restore catalytic performance. The regeneration method includes: a prewashing step (S12) of washing a denitration catalyst with water; a liquid agent cleaning step (S14) of immersing the denitration catalyst washed with water in a liquid agent containing an inorganic acid and a fluorine compound; a step of recovering the denitration catalyst from the liquid agent; and a finish washing step (S16) of washing the denitration catalyst recovered from the liquid agent with a finish cleaning liquid which is water or sulfamic acid-containing water.