GB738177A - Improvements in or relating to the production of phenolate solutions and phenols - Google Patents

Abstract

The invention comprises a new process for the production of a purified phenolate solution from tar-oils (preferably obtained by the distillation or coking of hard coal, lignite or oil-shale), which comprises forming a phenolate solution by mixing the tar-oil with an alkali solution, in such proportions that 1 mol. of the phenol to be removed is mixed with at least 1 mol. of alkali, and thereafter purifying the resulting phenolate solution by treatment with an adsorbing agent. Specified adsorbing agents are the basic oxides, hydroxides and carbonates of iron, magnesium and calcium, bleaching earths (e.g. bentonite, nontronite, beidellite and hectorite), alumina, "Luxmasse," and the "caustic slurry" obtained by heating phenolate lye residues with lime. p Preliminary purification of the tar-oils by steam treatment or extraction with benzine may be carried out before adsorbing the phenolate solution. In examples: (1) the phenolate lye obtained from a hard coal low temperature distillate (boiling-point range 170-360 DEG C.) is purified by treatment with benzine, then steam, and finally mixed with fuller's earth, decantation and filtration yielding a pure phenolate solution; (2) phenolate lye from tar oil (b.p. 270 DEG -360 DEG C.) is diluted with benzine and treated twice at the boiling point with washed clay to which ferric hydroxide may be added, the clarified phenolate solution then acidified, and phenols isolated by distillation; (3) phenolate lye from a tar oil fraction (b.p. 175-205 DEG C.), is treated with steam and then calcium hydroxide added. The lime slurry is separated, and crude phenols extracted by treatment with carbon dioxide, yielding phenol, o-cresol and m-, p-cresol on distillation. Other examples describe modifications of the above.