摘要
研究了维生素B12(VB12)催化纳米零价铁(nFe0)仿生还原降解工业级全氟辛磺酸(PFOS).结果表明,VB12催化nFe0不仅能够降解支链PFOS,而且也能够同时降解直链PFOS,这是首次报道直链PFOS的仿生还原降解.PFOS降解过程可用准一级动力学模型模拟,且升高温度有利于PFOS的还原降解去除和脱氟.超高效液相色谱-四级杆飞行时间质谱(UPLC-QTOF)定性分析表明,PFOS仿生降解产物包括4种全氟磺酸类(全氟碳链长度为C4~C7)、9种全氟羧酸类(全氟碳链长度为C2~C7、C10、C11和C13)和5种多氟代酸类(即H-全氟己酸、H-全氟庚酸、H-全氟辛酸、H2-全氟辛酸和H-全氟辛磺酸)化合物.全氟磺酸类和全氟羧酸类化合物首次在VB12仿生催化降解PFOS的产物之中检出,其中全氟十一烷酸(C10)、全氟十二烷酸(C11)和全氟十四烷酸(C13)等长链化合物第一次在降解PFOS过程中被发现.在降解样中检出的H-全氟烷烃(链长为C2~C7、C10、C11和C13)是否是PFOS的仿生降解产物,还有待进一步研究确认.
The reductive degradation of technical perfluorooctanesulfonate(PFOS)were investigated in a biomimetic system consisting of vitamin B12(VB12)as catalyst and nanoscale zero-valent iron(nFe0)as reductants.Both branched and linear PFOS could be degraded simultaneously,and the biomimetic degradation of linear PFOS was first reported.The degradation was well described by a pseudo-first-order kinetic model,and increasing the incubation temperature was favorable for the removal of PFOS and for its defluorination.Three types of PFOS degradation products,including 4 perfluoroalkylsulfonates(perfluorocarbon chain length:C4~C7),9perfluorocarboxylates(perfluorocarbon chain length:C2~C7,C10,C11,and C13),and 5 polyfluorinated acids(i.e.H-perfluorohexanoate,H-perfluoroheptanoate,H-perfluorooctanoate,H2-perfluorooctanoate,and H-perfluorooctanesulfonate)have been qualitatively determined by ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry(UPLC-QTOF).For the first time,Perfluoroalkylsulfonates and perfluorocarboxylates were detected among the biomimetic reduction products of PFOS catalyzed by VB12,while some long-chain perfluorocarboxylates,including perfluoroundecanoate(C10),perfluorodocecanoate(C11)and perfluorotetradecanoate(C13),were first reported as the degradation products during decomposition of PFOS.It was unclear whether H-perfluoroalkanes(carbon chain length:C2~C7,C10,C11,and C13)were the biomimetic degradation products of PFOS,and further investigation is warranted.
作者
杨宁
李飞
杨志敏
曹威
苑宝玲
YANG Ning;LI Fei;YANG Zhi-min;CAO Wei;YUAN Bao-ling(College of Civil Engineering,Huaqiao University,Xiamen 361021,China;Analytical and Testing Center of Huaqiao University,Xiamen 361021,China)
出处
《中国环境科学》
EI
CAS
CSCD
北大核心
2020年第11期4770-4778,共9页
China Environmental Science
基金
国家自然科学基金(51878300,51108197,51878301)
福建省自然科学基金(2017J01096)
泉州市科技计划项目(2018C084R)
厦门市科技重大专项(3502Z20191012)
华侨大学中青年教师科研提升资助计划(ZQN-YX602)
华侨大学研究生科研创新基金资助项目。
关键词
全氟辛磺酸
维生素B12
纳米零价铁
仿生降解
还原脱氟
PFOS
vitamin B12
nanoscale zero-valent iron
biomimetic degradation
reductive defluorination
