Abstract: The process for agglomerating and passivating the pulverulent used material and/or the pulverulent fines resulting from the production of organohalosilanes, comprises the mixing of this used material and/or fines with a binder chosen from aluminum silicates and the production of a solid agglomerated product by compression in a press, such as a roll type briquette machine. The invention also relates to the agglomerated product thus obtained and to its use in the recovery of certain metals, such as silicon and copper.

Abstract: Oxalyl chloride is prepared by (i) first esterifying ethylene glycol with trichloroacetyl chloride, (ii) next photochemically chlorinating the ester which results from the step (i), i.e., ethylene glycol bis-trichloroacetate, and (iii) then decomposing the tetrachloroethylene glycol bis-trichloroacetate thus formed into the desired oxalyl chloride and trichloroacetyl chloride, said steps (i) and (iii) being conducted in the absence of any reaction solvent, other than the trichloroacetyl chloride, and the chlorination step (ii) being conducted at a temperature of from about 50.degree. to 200.degree. C.