This technology is available from Temarex Corporation.
DESTRUCTION OF VOLATILE ORGANIC COMPOUNDS (VOCs)
Title: SELECTIVE OXIDATION CATALYSTS FOR HALOGENATED ORGANICS
Inventor(s):H. Greene, S. Chatterjee, B. Ramachandran
Disclosure 221 U.S. Patent 5,457,268
An improved process and catalyst compositions for the destruction of volatile organic compounds (VOCs) have been developed.The process includes the step of contacting the VOCs with an oxygen-containing gas in the presence of a catalyst which is a metal-exchanged, metal-impregnated aluminosilicate zeolite with at least one exchanged metal in the zeolite being selected from the group consisting of Ti, V, Cr, Co, Ni, Cu, Fe, Mo, Mn, Pd, and Pt, and at least one impregnated metal in the zeolite being selected from the group consisting of Ti, V, Cr, Co, Ni, Cu, Fe, Mo, Mn, Pd, and Pt, and wherein the difference between the exchanged and impregnated metals varies the activity and selectivity for VOC oxidation.
The preferred reaction temperature can vary from about 150oC to about 450oC and the contact time is from about 0.1 to 1.0 seconds. The CO/CO2 ratio and the Cl2/HCl ratio in the gaseous effluent can be varied through selection of one or more impregnated and exchanged metal cations in the zeolite.
The overall objectives of this invention are to further improve catalyst activity and selectivity, and to lower energy consumption costs.
Title: COMBINED SORBENT/CATALYST SYSTEM
Disclosure 180 U.S. Patent 5,414,201
This technology relates to the development of an effective dual function sorbent/catalyst media for the collection and oxidation of volatile organic compounds (VOCs).This system is designed to continuously adsorb chlorinated VOCs (CVOCs) from an ambient contaminated air stream, and periodically destroy them catalytically at elevated temperatures.
Because heating is periodic during the sorption/destruction cycle, energy savings of 90+% over typical continuous catalytic systems have already been demonstrated.Hence, with heating requirements being minimal, the energy needed could be supplied electrically, a method which is both environmentally clean and easily controlled.
The sorbent/catalyst medium have substantial capability for physisorption (storage) of CVOCs at room temperature while being active oxidation catalysts for these same entities at elevated (~350oC) temperatures.These media are synthesized from various cation impregnated/exchanged crystalline aluminosilicates and can be incorporated into a continuous process for effective CVOC destruction.
The advantage of this invention over current state-of-the-art equipment is the significant improved economy of operations achieved (e.g. savings in construction, operating and energy costs) via a combined sorbent/catalyst system which represents an effective alternative to the use of parallel carbon beds.
Title:CATALYSTS FOR THE DESTRUCTION OF HALOGENATED ORGANICS
Inventor(s):H. Greene, S. Chatterjee
Disclosure 133-CIP-DIV U.S. Patent 5,276,249
It is an objective of this invention to provide a novel, low temperature, highly selective, highly active catalyst.
A new class of metal-exchanged, metal-impregnated zeolite catalysts has been prepared for the oxidation of halogenated organics including chlorinated, fluorinated and chloro/fluoro hydrocarbons.These catalysts are supported or unsupported, comprising from 0 weight percent, hereinafter wt. %, to about 95 wt. % of a binder, from about 10 wt. % to about 95 wt. % of a metal-exchanged zeolite, and from about 0.2 wt. % to about 12 wt. % of an impregnated metal compound, said percentage being calculated as the metal loading on an oxide basis, where the metal in the metal-exchanged zeolite can be selected from the representative and illustrative group consisting of V, Cr, Co, Ni, Cu, Fe, Mo, and Mn and the impregnating metal compound can be selected from the representative and illustrative group consisting of compounds of Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Mo, Pd, and Pt.A process for making the catalysts and a process for the oxidation of the halogenated organics are disclosed which occur at relatively low temperatures from about 100oC to about 650oC, and at pressures near atmospheric and for residence times from about 0.01 seconds to about 20 seconds.
A process for making these catalysts is disclosed.Typical feeds include carbon tetrachloride, trichloroethylene, methylene chloride, and perchloroethylene.
Title:A NEW CATALYST SYSTEM AND PROCESS FOR DESTRUCTION OF HAZARDOUS CHLORINATED WASTES
Inventor(s):H. Greene, H. M. Cheung, R. Danals, S. Vimawala
Disclosure 108 U.S. Patent 5,075,273
New alkali metal salt vanadium oxide catalysts have been prepared for the oxidation of chlorinated hydrocarbons.The new catalyst can be supported or unsupported and shows excellent activity, selectivity, and resistance to poisons containing sulfur.The new catalyst can have a composition ranging from 1:0.05 alkali metal salt to vanadium ratio to 1:5 alkali metal salt to vanadium ratio.The catalyst operates at moderate temperature from about 300oC to 600oC with no apparent loss of vanadium.