New catalyst that eliminates efficiently chlorinated volatile organic compounds in gaseous streams

Description of the technology

The Carbonaceous Materials and Environment research group at the University of Alicante has developed a new catalyst that can efficiently remove chlorinated volatile organic compounds (particularly toxic 1,2-dichloroethane, widely used in various industrial processes) in gas streams at operating temperatures between 250-500 º C. These new catalysts (mixed oxides of cerium-praseodymium) have a low cost and both very active and stable, because they do not go through a significant deactivation process (unlike the catalysts commonly used at present). Consequently this is a novel technology suitable for the international market. The research group is looking for companies interested in acquiring this technology for its commercial development.

Specifications

In order to solve the above mentioned limitations, we are introducing a new catalyst based on cerium and praseodymium mixed oxides which allows an efficient control of chlorinated VOCs emissions, especially 1,2-dichloroethane (DCE, C2H4Cl2) present in the gaseous emissions from chemical plants, emissions with high stability and toxicity. Many of the catalysts used in the combustion of VOCs, when used to remove chlorinated organic compounds are deactivated in a short time due to chlorine poisoning by chlorine, and therefore stop working. Consequently there is a need for durable catalysts, in time and use, that allow the destruction of volatile organochlorine. In this sense, we have developed a new catalyst was developed that accelerates the burning of chorinated volatile organic compounds, whose generic formula is: CexPr1-xO2 (where 0 ≤ x ≤ 1) This type of catalysts are prepared by dissolving in water the corresponding precursors and precipitating / coprecipiting the corresponding hydroxides. They are then filtered, dried and burned. Once carried out the catalytic combustion tests, results have been checked by DRX, Raman Spectroscopy and XPS. Our conclusions are as follows: • All fresh catalysts have a fluorite-type structure. • After the catalytic tests, catalysts with an important cerium content keep their fluorite type structure, while those containing a high percentage of praseodymium, undergo a transformation phase to tetragonal structure. • Those catalysts rich in cerium suffer a slight chlorination, while those the rich in praseodymium undergo a chlorination both in surface and mass. • The mixed oxide catalysts CexPr1-XO2 have a high activity to accelerate the burning of chlorinated volatile organic compounds. • The stability of the catalysts depends on the composition of the mixed oxide used.

Main advantages of its use

• This novel catalytic system imply many advantages in relation to other similar products available in the market. Its main advantages are:• Highly efficient catalyst in the combustion of chlorinated volatile organic compounds (especially for in the case of the toxic and stable 1,2-dichloroethane).• High stability and durability in the reaction process• Low manufacturing cost• High efficiency: a small quantity of catalists require• It does not produce secondary pollutants (nitrogen oxides)• It allows the treatment of gaseous streams at low temperature (between 250-500 º C).

Applications

• This innovative and stable catalytic system for the efficient combustion of volatile organochlorine compounds (especially of 1, 2-dichloroethane) has a higly efficient performance in the control of pollutant emissions in the following industrial sectors:• Production of polyvinyl chloride (PVC).• Cleaning of textiles.• Cleaning of metal parts.• Dispersion of plastics and elastomers.• Paints• Enamels and varnishes.• Waste gases from chemical plants.• Processes of evaporation of solvents.• Decontamination of soils and waters.