摘要
为了探究生物炭如何协助溶磷细菌对Cu的修复,本研究选择以污泥为原料生产的微酸性富磷生物炭(SB)和溶磷细菌(PSB),通过测定生物炭的理化特性、微生物形貌和重金属含量,研究了生物炭强化PSB对水体中Cu^(2+)(1000 mg/L)的修复机制。结果表明,PSB对Cu^(2+)的去除率较低,SB协助后,二者联合对Cu^(2+)的去除效果比PSB/SB单独处理的提升1~120倍。衰减全反射(ATR)、X线衍射(XRD)和扫描电子显微镜(SEM)结果表明SB表面有稳定的碳酸盐和磷酸盐矿物形成。在Cu^(2+)胁迫下,X线光电子能谱(XPS)结果表明,PSB中的Cu^(+)占62.7%;但在SB协助下,PSB中的Cu^(+)占比降至43.55%,而Cu^(2+)显著增至56.45%。电化学结果发现,PSB+Cu上Cu还原电位十分明显,而SB+PSB+Cu同时具备氧化和还原2种电位,进一步证实生物炭联合微生物提高二者的氧化性能。生物炭丰富的孔隙和表面可以藏匿PSB和固定Cu^(2+),而生物炭能够通过自身氧化性能和提高微生物生物性能,将Cu^(+)转化为Cu^(2+),从而降低Cu^(2+)转化为Cu^(+)所带来的毒性。因此,富磷生物炭可以成为溶磷细菌修复重金属污染的优秀反应平台。
To explore how biochar can assist phosphate solubilizing bacteria in the remediation of Cu,we selected slightly acidic phosphorus-rich biochar(SB)produced from sludge and phosphate solubilizing bacteria(PSB)as raw materials,and discussed the remediation mechanism of Cu^(2+)(1000 mg/L)in water by biochar enhanced PSB by measuring the physicochemical properties,microbial morphology and heavy metal content of the biochar.The results show that the removal of Cu^(2+)by PSB is low,and with the assistance of SB,the removal effect of Cu^(2+)by the combination of the two is 1-120 times higher than that by PSB/SB alone.The results of attenuated total reflectance(ATR),X-ray diffraction(XRD)and scanning electron microscope(SEM)analysis show that there are stable carbonate and phosphate minerals on the surface of SB.Under Cu^(2+)stress,X-ray photoelectron spectroscopy(XPS)results show that Cu^(+)account for 62.7%in PSB,while Cu^(+)decrease to 43.55%and Cu^(2+)significantly increase to 56.45%in PSB with SB assistance.Electrochemical results show that the Cu reducing potential is very obvious on PSB+Cu,while Sb+PSB+Cu has both oxidation and reduction potential,which further proves that biochar combined with microorganisms could improve the oxidation performance of both.The rich pores and surface area of biochar could harbor PSB and immobilize Cu^(2+).In addition,biochar could convert Cu^(+)to Cu^(2+)through its own oxidation performance and improve the biological performance of microorganisms,thus reducing the toxicity caused by converting Cu^(2+)to Cu^(+).Therefore,phosphorus-rich biochar could be an excellent reaction platform for phosphate solubilizing bacteria to remediation of heavy metal pollution.
作者
李辰
陈颢明
胡亦舒
赖韦唯
卢雨琦
娜扎发提·穆罕麦提江
闵芳芳
李真
LI Chen;CHEN Haoming;HU Yishu;LAI Weiwei;LU Yuqi;NAZHAFATI Muhanmaitijiang;MIN Fangfang;LI Zhen(School of Environmental and Biological Engineering,Nanjing University of Science and Technology,Nanjing 210094,China;School of Resources and Environmental Sciences,Nanjing Agricultural University,Nanjing 210094,China)
出处
《生物加工过程》
CAS
2022年第6期658-664,共7页
Chinese Journal of Bioprocess Engineering
基金
国家自然科学基金(42007105)
南京理工大学科研启动基金(AZ89991/197)。
关键词
生物炭
溶磷细菌
重金属胁迫
矿物形成
价态变化
生物修复
biochar
phosphate solubilizing bacteria
heavy metal stress
mineral formation
valence state changes
bioremediation
