EPA Science Inventory

Regeneration of Three-Way Automobile Catalysts using Biodegradable Metal Chelating Agent – S, S-Ethylenediamine Disuccinic Acid (S, S-EDDS)

Citation:

Subramanian, B., S. Y. Christou, A. M. Efstathiou, V. V. NAMBOODIRI, AND D. D. Dionysiou. Regeneration of Three-Way Automobile Catalysts using Biodegradable Metal Chelating Agent – S, S-Ethylenediamine Disuccinic Acid (S, S-EDDS). JOURNAL OF HAZARDOUS MATERIALS. Elsevier Science Ltd, New York, NY, 186(2-3):999-1006, (2011).

Impact/Purpose:

To inform the public.

Description:

Regeneration of the activity of three-way catalytic converters (TWCs) was tested for the first time using a biodegradable metal chelating agent (S, S. Ethylenediamine disuccinic acid (S, S-EDDS). The efficiency of this novel environmentally friendly solvent in removing various contaminants such as P, Zn, Pb, Cu and S from commercial aged three-way catalysts, and improving their catalytic perfomance towards CO and NO pollutants removal has been investigated. Four samples of catalysts from the front and rear inlets of two different TWCs with different mileages and aged under completely different driving conditions were investigated. The catalysts were characterized using various techniques, such as X-ray diffraction (XRD), Scanning electron microscopy (SEM), and Brunauer-Emmett-Teller (BET) surface area measurements (N(2) adsorption at 77K). Quantitative ICP-MS analyses and SEM-EDS studies show the removal of Zn, P and Pb. SEM-EDS images obtained at low magnification (50µm) showed considerable differences in the surface morphology and composition after washing with S, S-EDDS. However, XRD studies indicated neither little to no removal of major contaminant compound phases nor major structural changes due to washing. Correspondingly, little or no enhancement in BET surface area was observed between the used and washed samples. Light-off curves show that the regeneration procedure employed can effectively improve the catalytic performance towards NO pollutant.

URLs/Downloads:

REGENERATION OF THREE-WAY AUTOMOBILE CATALYSTS USING BIODEGRADABLE METAL CHELATING AGENT – S, S-ETHYLENEDIAMINE DISUCCINIC ACID (S, S-EDDS)   Exit

Website   Exit

Record Details:

Record Type: DOCUMENT (JOURNAL/PEER REVIEWED JOURNAL)
Product Published Date: 02/28/2011
Record Last Revised: 03/18/2011
OMB Category: Other
Record ID: 234003

Organization:

U.S. ENVIRONMENTAL PROTECTION AGENCY

OFFICE OF RESEARCH AND DEVELOPMENT

NATIONAL RISK MANAGEMENT RESEARCH LABORATORY

WATER SUPPLY AND WATER RESOURCES DIVISION

WATER QUALITY MANAGEMENT BRANCH