Destruction of cyanide waste solutions using chlorine dioxide, ozone and titania sol

• Published in: Waste management (Elmsford) Vol. 23; no. 2; pp. 183 - 191
• Main Authors: Parga, J.R, Shukla, S.S, Carrillo-Pedroza, F.R
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.01.2003; New York, NY Elsevier Science
• Subjects: Applied sciences; CHLORINE; Chlorine Compounds - chemistry; CHLORINE OXIDES; Coloring Agents - chemistry; Control equipment; CYANIDES; Cyanides - chemistry; Effluents; ENVIRONMENTAL SCIENCES; Exact sciences and technology; Hydrocyclones; Industrial wastewaters; LIQUID WASTES; MILLING; MINERAL INDUSTRY; Mining; Mining industry; Oxidants, Photochemical - chemistry; OXIDATION; Oxidation-Reduction; Oxides - chemistry; OZONE; Ozone - chemistry; PHOTOLYSIS; Pollution; PONDS; Precious metals; Recovery; SOLS; TAILINGS; Titanium - chemistry; Titanium dioxide; TITANIUM OXIDES; TOXICITY; Waste Disposal, Fluid - methods; WASTE MANAGEMENT; Wastewaters; Water treatment and pollution; Transition metal Compounds; Photocatalysis; Ozone; Cyanides; Chemical degradation; Photochemical reaction; Chlorine dioxide; Stirred tank reactor; Titanium Oxides; Ozonization; Ultraviolet radiation; Hydrocyclone; Batchwise; Photolysis; Industrial waste water; Physicochemical purification; Oxidation; Waste water purification; Performance; Mining industry
• ISSN: 0956-053X; 1879-2456
• DOI: 10.1016/S0956-053X(02)00064-8

Increasingly, there are severe environmental controls in the mining industry. Because of lack of technological advances, waste management practices are severely limited. Most of the wastes in the milling industrial effluents are known to contain cyanides and it is recognized that after extraction and recovery of precious metals, substantial amounts of cyanide are delivered to tailings ponds. The toxicity of cyanide creates serious environmental problems. In this paper we describe several methods for the treatment of cyanide solutions. These include: (1) cyanide destruction by oxidation with chlorine dioxide (ClO 2) in a Gas-Sparged Hydrocyclone (GSH) reactor; (2) destruction of cyanide by ozone (O 3) using a stirred batch reactor, and finally, (3) the photolysis of cyanide with UV light in presence of titania sol. In all cases excellent performance were observed as measured by the extent and of the destruction.