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Chlorinated solvents such as tetrachloroethylene (PCE) in aquifers should be remediated due to their toxicity that limited the use of groundwater resources. Nanoscale zero-valent iron (NZVI) and palladized/iron (Pd/Fe) bimetallic particles were synthesized and employed to react with PCE in water to investigate its degradation behaviors. Batch tests were conducted in a 1 L serum bottle under airtight and anaerobic conditions with parameters of Pd mass contents, temperature, pH, and dispersant. The results showed that specific reaction rate constants (kSA) of 5 mg L-1 PCE degraded by metal particles at 30°C in the absence of dispersant enhanced with higher Pd mass contents on the Pd/Fe particles. Degradation rates of PCE increased as the reaction temperature was raised from 20 to 40°C. Carboxymethyl cellulose (CMC), a dispersant, enhanced the kSA values of NZVI and 1:100 Pd/Fe particles by a factor of about 33 and 4 at 30°C, respectively. The tests of pH control with buffer solution indicated that PCE degradation rates were promoted under acid and neutral conditions. Additionally, no chlorinated by-products were observed during the experimental period in each test. This study shows that effective dechlorination of PCE in water could be achieved by synthesized Pd/Fe and NZVI particles coupled with CMC dispersant. [ABSTRACT FROM AUTHOR]