Accession Number : ADA317926

Title :   An Evaluation of the Technical Feasibility of Photocatalytic Oxidation and Phase Transfer Catalysis for Destruction of Contaminants from Water.

Descriptive Note : Final rept. 1 May 90-31 Dec 94,

Corporate Author : MICHIGAN TECHNOLOGICAL UNIV HOUGHTON

Personal Author(s) : Crittenden, John c. ; Hand, David W. ; Zhang, Yin ; Mullins, Michael E.

PDF Url : ADA317926

Report Date : JUN 1996

Pagination or Media Count : 64

Abstract : Present efforts have developed photocatalysts best suited for the destruction of hydrophobic and hydrophilic organic contaminants. Using solar Insolation with Pt-TlO2 supported on silica gel, the best supported photocatalyst identified in a systematic evaluation, can mineralize trichioroethylene (8 mg/l) completely in a short time of 1.3 minutes. The destruction rate using this supported catalyst is four times greater than that using the optimized slurry made with the best photocatalyst Identified, and sixteen times greater than using a slurry made with the best commercially available catalyst. Catalyst supports are successfully surface-modified to increase adsorption capacity and in turn the overall destruction rates. Using solar insolation or artificial light sources for the applications in both water and air phases, the fixed-bed processes utilizing the supported photocatalyst have successfully mineralized other compounds with a wide range of adsorbabilities and photoactivities. Present efforts also have developed an adsorbent regeneration strategy: using saturated steam followed by photocatalysis to regenerate the spent adsorbents, and to destroy the desorbed organic compounds in the steam or steam condensate. Limited efforts have been made to model photocatalysis and steam desorption. The technologies have been tested successfully in the field at Tyndall AFB, FL and K.I. Sawyer AFB, MI and at a water treatment plant in Wausau, WI.

Descriptors :   *PHOTOCHEMICAL REACTIONS, *WATER TREATMENT, *OXIDATION, *CONTAMINANTS, *CATALYSIS, TEST AND EVALUATION, OPTIMIZATION, STRATEGY, MODELS, AIR, WATER, ADSORPTION, DESTRUCTION, RATES, PHASE, SATURATION, LIGHT SOURCES, SLURRIES, FEASIBILITY STUDIES, STATIONARY, ORGANIC MATERIALS, ORGANIC COMPOUNDS, CATALYSTS, SUPPORTS, TRANSFER, INDUSTRIAL PLANTS, RANGE(EXTREMES), STEAM, DESORPTION, BEDS(PROCESS ENGINEERING), CONDENSATION, ADSORBENTS, REGENERATION(ENGINEERING), SILICA GELS, HYDROPHILIA.

Subject Categories : Inorganic Chemistry
      Physical Chemistry
      Atomic and Molecular Physics and Spectroscopy
      Water Pollution and Control

Distribution Statement : APPROVED FOR PUBLIC RELEASE