不同钙源对产脲酶细菌固定水中 Pb²⁺的效果及机制

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关键词：微生物诱导碳酸盐沉淀；化学钙源；废弃物钙源； Pb2+ 固定中图分类号：X703；X172 文献标志码：A 文章编号：1672-2043（2025）09-2386-10 doi：10.11654/jaes.2024-0800

Abstract：To investigate the effect of diferent calcium sources on the fixation of Pb2+ by microbially induced carbonate precipitation （MICP），astrainofurease-producingbacterumN32wasslected，thenanalyzedtheimpactofdiferentcalciumsources，including chemicalsouesi.cde，almaceate，cmoxidendwasesourcsi.gsels，stersels） the strain's capacity to immobilize Pb2+ in aqueous solutions by means of culture tests.Furthermore，the study utilized scanning electron microscopyeeispersivesctroeer（EED），X-adiracti，ndFourierrafofraredectroo elucidatethemechanismsunderpiingtheimmoblizationprocess.ResultsindicatedoptimalgrowthofthestrainswithinapHrangeof 6-9，showcasing their capacity to thrive even at a Pb2+ concentration of 1000mg⋅L-1 ，implying high tolerance to Pb.It was found that the （204号 Pb2+ fixation rate by strain NT32 was low（ 27.05% ）with no-calcium treatment，and the Pb2+ fixation rate was increased by 99.60% ， （20 50.15% ，and 87.56% after the additions of calcium chloride，calcium acetate，and calcium oxide.When calcium chloride was added at ratio of 1%（m/V） ，the Pb2+ fixation rate （ 99.60% ）and the urease activity （53.1U⋅mL-1 ）were significantly better than other treatments. However， thewaste calcium source treatmentshad less effect in Pb2+ fixation，and the highest Pb2+ fixation rate was observed at 0.5%- clam shell treatment （ 41.58% ）.Characterization findings revealed distinct crystal morphologies of CaCO 3 with varying calcium sources. Specificallyalcichlodepredominantlyieldedthrmodnamicallstablealcite，hilealcumoxidepodcearagonitedlite whilecalcitedgisieliallylbbybidl groups jointly contribute to Pb2+ fixation，with all treatments yielding carbonate compounds，thereby highlighting the critical role of carbonate precipitation in Pb2+ fixation.In summary，the addition of exogenous calcium can significantly improve the fixation of Pb2+ via urease-producing bacteria，and the chemical calcium source is superior to the waste calcium source.

Keywords： microbially induced carbonate precipitation; chemical calcium sources; waste calcium sources; Pb2+ fixation

随着工业化的快速发展，大量重金属被释放到环境中，导致环境污染日趋严重。（剩余16774字）