FIXED PHOTOCATALYST CARRYING PALLADIUM, TREATMENT OF ORGANIC SUBSTANCE CONTAINED IN PLATING WASTE LIQUID AND TREATMENT DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a method and a device for oxidizing and treating organic substance contained in plating waste liquid in which a photocalyst is used and oxidative decomposition is efficiently performed and also recovering operation of the catalyst is omitted and continuous treatment is enabled. SOLUTION: The fixed photocatalyst is obtained by forming a transparent thin film of anatase-type titanium dioxide on a transparent quartz glass tube and immersing the thin film into a palladium chloride solution (pH 4) and selectively carrying palladium having the rate of 1-10 wt.% for titanium dioxide, in only a region on the conduction band side by reduction deposition through irradiation of ultraviolet rays. A plurality of quartz glass tubes supporting the photocalyst on the wall surface are erected in an irradiation region of ultraviolet rays in plating waste liquid. The pH of waste liquid is held at 1-4 and while blowing oxygen or air into waste liquid, ultraviolet rays are irradiated from a high-pressure mercury lamp or the like. Organic substance contained in waste liquid is subjected to oxidative decomposition so as to obtain carbon dioxide and water.