Date of Award

3-2005

Document Type

Thesis

Degree Name

Master of Science

Department

Department of Systems Engineering and Management

First Advisor

Mark N. Goltz, PhD

Abstract

In this study, application of a catalytic reactor to facilitate chemical reduction of perchlorate was investigated. Palladium-coated pellets were used as the catalyst, and formic acid was used as the reductant. Reactor performance was evaluated under a variety of operating conditions (influent pH, reductant concentration, residence time). Very little perchlorate reduction was observed under any operating condition. At best, approximately 8% perchlorate reduction was observed. This small reduction efficiency is clearly not sufficient for environmental treatment applications. Perchlorate strongly adsorbed to the catalyst at low pH (3 - 3.3). At higher pH (4 - 10), little adsorption was observed. This pH behavior may be the result of dissociation of formic acid (pKa ~ 3.75). It is possible that perchlorate reduction was limited by the amount and speciation of formic acid in the system. Maximum perchlorate reduction was observed at high reductant concentration (10 millimolar formic acid) and low pH (minimized dissociation of formic acid to formation). Increasing the formic acid concentration and reducing the upward pH drift of the bulk fluid (via reduced residence time) may improve perchlorate reduction.

AFIT Designator

AFIT-GES-ENV-05M-01

DTIC Accession Number

ADA434460

Download

Share

COinS