Abstract: Chlorine is produced by oxidizing byproduced hydrogen chloride. An offgas containing hydrogen chloride as a byproduct is reacted with oxygen at 300.degree.-500.degree. C. in the presence of a catalyst which contains chromic oxide (Cr.sub.2 O.sub.3) as a principal component. The resulting gas is cooled rapidly and then washed with water to recover vaporized chromium. The hydrogen chloride is then absorbed in water to recover it as an aqueous hydrochloric acid solution. The still remaining portion of the resultant gas is washed with sulfuric acid to remove water from the same, followed by compression and cooling. The resulting liquefied chlorine is separated. The still remaining gas composed principally of oxygen is thereafter returned to the oxidation step.

Abstract: A process for producing m-phenoxybenzyl alcohol which comprises reacting chlorobenzene with m-hydroxybenzyl alcohol in the presence of a copper compound as a catalyst and a base, characterized in that chlorobenzene is added to a polar solvent having a higher boiling point than chlorobenzene, the amount of chlorobenzene being 0.05 to 4.0 times the weight of the polar solvent; at least one compound selected from alkali hydroxides, alkali carbonates and alkali bicarbonates is used as the base in an amount of 1.0 to 2.0 gram-equivalents per mole of m-hydroxybenzyl alcohol; and the reaction is carried out at a temperature of 140.degree. to 200.degree. C. while removing the generated water as an azeotrope with chlorobenzene.

Abstract: A process for producing m-hydroxybenzyl alcohol which comprises electrolytically reducing m-hydroxybenzoic acid in an acidic aqueous solution at a temperature of 20.degree. to 70.degree. while m-hydroxybenzyl alcohol is present always in the electrolytic solution. The constant presence of m-hydroxybenzyl alcohol is effected by (1) continuously adding m-hydroxybenzoic acid to the electrolytic solution in an amount corresponding to that consumed as the electrolytic reaction proceeds, or (2) by continuously adding m-hydroxybenzoic acid and the acidic aqueous solution to the electrolytic solution.

Abstract: A 2-(substituted aryl)propionaldehyde of the formula, ##STR1## (wherein Ar denotes ##STR2## is produced in high yield by reacting a methyl (substituted aryl) ketone of the formula ##STR3## with phenyldimethylsulfonium methylsulfate of the formula, ##STR4## in the presence of alkali metal hydroxide to obtain a reaction mixture containing 2-(substituted aryl)1,2-epoxypropane of the formula, ##STR5## and thioanisole, and subjecting the reaction mixture to contact with anhydrous MgCl.sub.2. The propionaldehyde compound is also produced in high yield by contacting the epoxypropane compound with anhydrous MgCl.sub.2 in the presence of a soft nucleophile such as a sulfide, a thiol and a phosphine.

Abstract: In a process for the preparation of mononitrochlorobenzene by nitration of chlorobenzene using a mixed acid of nitric acid and phosphoric acid, the nitration reaction is carried out by using a molar ratio of nitric acid to chlorobenzene of not more than equimol in the presence of a concentrated phosphoric acid as the phosphoric acid component at temperatures of 50.degree.-120.degree. C. while maintaining the concentration of phosphoric acid to 72.4 weight % as P.sub.2 O.sub.5 or more during the reaction.

Abstract: A process for preparing stable anhydrous sodium dithionite which comprises reacting formic acid or sodium formate, sodium hydroxide, and sulfurous acid anhydride in hydrous methanol, wherein an aqueous solution of sodium carbonate or sodium hydroxide is added to the slurry after the reaction, and stabilized anhydrous sodium dithionite is separated from the slurry.

Abstract: In the production of anhydrous sodium dithionite by reacting sodium formate, an alkaline sodium compound and sulfurous acid anhydride in hydrous methanol, a process for treating the mother liquor, which comprises adding an alkali to the mother liquor left after the separation of the resulting anhydrous sodium dithionite to adjust its pH to at least 8, separating the solids precipitated, and oxidizing the filtrate with an oxidizing agent.

Abstract: In the production of anhydrous sodium dithionite by reacting sodium formate, an alkaline sodium compound and sulfurous acid anhydride in hydrous methanol, a process for treating the mother liquor, which comprises cooling the mother liquor left after the separation of the resulting anhydrous sodium dithionite to a temperature in the range of +5.degree. to -30.degree. C, and separating the precipitated sodium thiosulfate by filtration.