Abstract: A tungsten-containing catalyst associated with coke containing vanadium and nickel is recovered by a method which includes steam gasification, low temperature burning to remove at least a portion of the coke and selective extraction of the nickel and vanadium.

Abstract: Regeneration of an aromatics processing catalyst is effected in the absence of a gas cooler and a gas-liquid separator with a continuous loop flow of an oxidizing gas stream by removing a portion of said continuous closed loop flow and introducing therein a quantity of a low moisture content molecular oxygen containing gas effective to maintain a molecular oxygen content no greater than 1.0 mole percent and a water partial pressure no greater than about 1.0 psi.

Abstract: Improved aromatic conversion processes are provided by novel regeneration techniques. Aromatic processes that would benefit from this invention include those processes using catalysts comprising zeolites having a silica to alumina mole ratio of at least about 12 and a constraint index within the approximate range of 1 to 12 and which require regeneration to burn off coke from said catalysts. The improvement of the instant invention resides in conducting said regeneration in the presence of steam under controlled conditions to enhance the activity of the catalysts.

Abstract: A spent solid sorbent resulting from the removal of hydrogen sulfide from a fuel gas flow is regenerated with a steam-air mixture. The mixture of steam and air may also include additional nitrogen or carbon dioxide. The gas mixture contacts the spent sorbent containing metal sulfide at a temperature above 500.degree. C. to regenerate the sulfide to metal oxide or carbonate. Various metal species including the period four transition metals and the lanthanides are suitable sorbents that may be regenerated by this method. In addition, the introduction of carbon dioxide gas permits carbonates such as those of strontium, barium and calcium to be regenerated. The steam permits regeneration of spent sorbent without formation of metal sulfate. Moreover, the regeneration will proceed with low oxygen concentrations and will occur without the increase in temperature to minimize the risk of sintering and densification of the sorbent.

Abstract: Cyclohexane-1,3-diones are prepared by passing .delta.-ketocarboxylic acid esters in the gaseous phase over a temperature of from 250.degree. C. to 500.degree. C. at a catalyst. The catalyst contains at least one element of groups III B or IV B of the Periodic System in the form of a compound. Particularly preferred catalysts are thorium compounds on charcoal carriers.