Dichloromethane photodegradation using titanium catalysts

The use of titanium dioxide and titanium aluminosilicates in the photocatalytic destruction of chlorinated hydrocarbons is investigated. Titanium-exchanged clays, titanium-pillared clays, and titanium dioxide in the amorphous, anatase, and rutile forms are used to photocatalytically degrade dichloromethane to hydrochloric acid and carbon dioxide. Bentonite clays pillared by titanium dioxide are observed to be more catalytically active than titanium-exchanged clays. Clays pillared by titanium aluminum polymeric cations display about the same catalytic activity as that of titanium-exchanged clays. The rutile form of titanium dioxide is the most active catalyst studied for the dichloromethane degradation reaction. The anatase form of titanium dioxide supported on carbon felt was also used as a catalyst. This material is about five times more active than titanium dioxide-pillared clays. Degradation of dichloromethane using any of these catalysts can be enhanced by oxygen enrichment of the reaction solution or by preirradiating the catalyst with light.

[1]  R. Burch,et al.  Zr-Containing pillared interlayer clays: I. Preparation and structural characterisation , 1986 .

[2]  S. Suib,et al.  Uranyl clay photocatalysts , 1985 .

[3]  D. Ollis,et al.  Heterogeneous photoassisted catalysis: Conversions of perchloroethylene, dichloroethane, chloroacetic acids, and chlorobenzenes , 1984 .

[4]  D. Ollis,et al.  Heterogeneous photocatalysis: Degradation of dilute solutions of dichloromethane (CH2Cl2), chloroform (CHCl3), and carbon tetrachloride (CCl4) with illuminated TiO2 photocatalyst , 1983 .

[5]  Barry G. Oliver,et al.  Chlorobenzenes in sediments, water, and selected fish from Lakes Superior, Huron, Erie, and Ontario , 1982 .

[6]  Daniel C. Harris,et al.  Quantitative Chemical Analysis , 1968, Nature.

[7]  J. Tanguay,et al.  Comparison of the photochemical and photophysical properties of clays, pillared clays, and zeolites , 1986 .

[8]  M. Hattori,et al.  High surface area solids obtained by intercalation of iron oxide pillars in montmorillonite , 1984 .

[9]  G. Brindley,et al.  High Surface Area Solids Obtained by Reaction of Montmorillonite with Zirconyl Chloride , 1979 .

[10]  M. Occelli,et al.  Physicochemical Properties of Montmorillonite Interlayered with Cationic Oxyaluminum Pillars , 1983 .

[11]  S. Suib,et al.  Chromium(III)-doped pillared clays (PILC's) , 1986 .

[12]  D. Ollis,et al.  Solar photoassisted catalytic decomposition of the chlorinated hydrocarbons trichloroethylene and trichloromethane , 1984 .

[13]  Shoji Yamanaka,et al.  Preparation and properties of titania pillared clay , 1987 .

[14]  R. M. Barrer,et al.  Activation of montmorillonite by ion exchange and sorption complexes of tetra-alkyl ammonium montmorillonites , 1955 .

[15]  S. Suib,et al.  Physical and chemical stabilities of pillared clays containing transition metal ions , 1986 .

[16]  J. Barksdale.  Titanium, Its Occurrence, Chemistry, and Technology , 1950 .

[17]  D. Ollis,et al.  Degradation of chloroform by photoassisted heterogeneous catalysis in dilute aqueous suspensions of titanium dioxide. , 1983, Environmental science & technology.

[18]  U. Shani,et al.  Cross-Linked Smectites. I. Synthesis and Properties of Hydroxy-Aluminum-Montmorillonite , 1978 .

[19]  L. Gatineau,et al.  Pillaring Processes of Smectites with and Without Tetrahedral Substitution , 1987 .

[20]  David F. Ollis,et al.  Photoassisted heterogeneous catalysis: the degradation of trichloroethylene in water , 1983 .

[21]  M. Boudart.  Structure of metallic catalysts , 1978 .

[22]  E. Eyring,et al.  An ESR Study of Titanium(III) Exchanged Zeolite A. , 1980 .

[23]  T. Pinnavaia,et al.  New chromia pillared clay catalysts , 1985 .

[24]  J. Sterte.  Synthesis and Properties of Titanium Oxide Cross-Linked Montmorillonite , 1986 .