Abstract: Unstabilized vinylbenzyl chloride and substituted vinylbenzyl chlorides are essentially inert with respect to surfaces of aluminum or alloys containing at least 90 percent by weight of aluminum in sharp contrast to benzyl chloride and similar substituted benzyl halides. Aluminum and such alloys of aluminum are thus practical materials of construction for making containers, pipes, stills, still column packing and the like for handling vinylbenzyl chloride.

Abstract: In the catalytic hydrogenation of a substance in a water-immiscible organic liquid medium, a metallic hydrogenation catalyst is conveniently and effectively dispersed in the reaction mixture by addition as an emulsion of an aqueous solution of a salt of the metal in the liquid medium. The method is particularly applicable to the liquefaction of coal.

Abstract: Low yield thermal cracking of a hydrocarbon such as ethylbenzene caused by contact with active metal surfaces in a catalytic dehydrogenation reactor is reduced by coating the metal surfaces, particularly those in the feed inlet end, with a thin layer of an inactivating metal or metal compound, such as V.sub.2 O.sub.5, preferably in an inert ceramic medium.

Abstract: Hydrogen sulfide and lower alkyl mercaptans are selectively extracted from a gas stream by contacting the stream with piperazinone or an alkyl substituted piperazinone which may contain a substantial proportion of water. The absorbed sulfur compounds can be regenerated by heating the extraction liquid to about 85.degree.-150.degree. C.

Abstract: In the hydrogenation of coal slurried in recycle oil in the presence of a suspended hydrogenation catalyst, a substantial proportion of the catalyst can be recovered for recycle to the process by using a catalyst which is significantly more finely divided than the ash particles from the coal, subjecting the hydrogenated slurry to a gravity concentration process whereby the coarser, ash particles are selectively concentrated in a lower layer and a relatively larger proportion of the finer catalyst particles remain suspended in the supernatant oil, and recycling at least a part of the supernatant oil containing suspended catalyst to the coal hydrogenation process.