Tetrachloroethene (Perchloroethylene, PCE) is an industrial chlorinated solvent and a slowly degradable compound. The degradability of PCE by Sphingopyxis ummariensis bacteria in both suspended and immobilized culture systems was investigated under aerobic conditions. For this purpose, yeast extract and glucose were used as co-substrates. Various experiments were performed on immobilized cells in a gas-recycling fixed-bed batch (GRFB) bioreactor packed with polyethylene. The results showed that PCE could be highly removed in the concentration range of 0.04–0.76 mM, but the removal occurred more efficiently in lower concentrations. It was also observed that the rate of PCE degradation decreased from 100% to 80%, and the dechlorination percentage decreased from 84 to almost 70% as the initial PCE concentration increased from 0.04 to 0.76 mM. The first-order kinetic model was best fitted to the degradation behavior in the bioreactor with kinetic rate constants in the range of 0.088–0.044 h^–1. In addition, the degradation trend of an equimolar mixture of PCE and trichloroethylene (TCE) in the GRFB bioreactor showed, TCE is a competitor of PCE and its degradation rate is higher than that of PCE. The performance of the GRFB bioreactor proved that it is reliable for the aerobic removal of chlorinated hydrocarbons.

四氯乙烯（全氯乙烯，PCE）是一种工业氯化溶剂，是一种缓慢降解的化合物。ummariphensis ummariensis对PCE的降解性在有氧条件下研究了悬浮培养系统和固定培养系统中的细菌。为此，将酵母提取物和葡萄糖用作共底物。在装有聚乙烯的气体循环固定床批量（GRFB）生物反应器中，对固定化细胞进行了各种实验。结果表明，在0.04-0.76 mM的浓度范围内，PCE可以被高度去除，但在较低的浓度下，去除效率更高。还观察到，随着初始PCE浓度从0.04 mM增至0.76 mM，PCE降解率从100％降低至80％，脱氯百分比从84％降低至近70％。一级动力学模型最适合生物反应器中的降解行为，动力学速率常数范围为0.088–0.044 h^–1。另外，在GRFB生物反应器中，PCE和三氯乙烯（TCE）等摩尔混合物的降解趋势表明，TCE是PCE的竞争者，其降解率高于PCE。GRFB生物反应器的性能证明，它对于需氧去除氯代烃是可靠的。