Reaction of decabromodiphenyl ether with organo-modified clay-templated zero-valent iron in water-tetrahydrofuran solution: nano- to micrometric scale effects
Reaction of decabromodiphenyl ether with organo-modified clay-templated zero-valent iron in water-tetrahydrofuran solution: nano- to micrometric scale effects
复制标题
十溴二苯醚与有机改性粘土模板零价铁在水-四氢呋喃溶液中的反应：纳米至微米尺度效应
DOI：
10.1016/j.jhazmat.2022.130538
复制
发表时间：
2023
影响因子：
13.6
通讯作者：
Li H.
中科院分区：
文献类型：
--
作者：
Yu K.;Lv Y.N.;Liu C.;Boyd S. A.;Teppen B. J.;Li H.
用四甲基铵(TMA)、三甲基苯基铵(TMPA)和十六烷基三甲基铵(HDTMA)对蒙脱石模板化纳米零价铁(CZVI)进行改性，制得有机模板化ZVI(OCZVI)。以十溴二苯醚(DBDE)在四氢呋喃(THF)-水二元溶液中的降解为基础，评价了不同OCZVI的反应活性。对OCZVI中间层的纳米尺度表征表明，粘土颗粒在四氢呋喃/水溶液中具有三个基本间距的结构域。在50%THF溶液中，TMPA修饰促进了DBDE微区的形成，其层间距为1.56 nm，从而促进了DBDE的降解。在微观尺度上，在90%THF溶液中，TMA和TMPA改性倾向于促进OCZVI粒子的团聚，而HDTMA改性降低了团聚，高比例的改性产生了粘性凝胶结构。在90%四氢呋喃溶液中较快的沉积过程(与在50%四氢呋喃溶液中相比)和形成凝胶结构可以减少DBDE对层间反应性nZVI的访问，导致反应速度显著降低。这些结果为粘土的有机改性提供了重要的启示，这种改性可以改变粘土在有机-水二元溶液中的取向和分散性，从而在受限的粘土表面实现预期的反应活性。
Smectite clay-templated nanoscale zero-valent iron (CZVI) was modified with tetramethylammonium (TMA), trimethylphenylammonium (TMPA) and hexadecyltrimethylammonium (HDTMA) to achieve organoclay-templated ZVI (OCZVI). The reactivity of various OCZVIs was evaluated on the basis of degradation of decabromodiphenyl ether (DBDE) in tetrahydrofuran (THF)-water binary solution. Characterization of OCZVI interlayer at nanometric scale indicated that the clay particles had the domains with three basal spacings in the THF/water solution. In the 50 % THF solution TMPA modification promoted the formation of the domains with a basal spacing at 1.56 nm, which could promote the degradation of DBDE. At the micrometric scale, in the 90 % THF solution TMA and TMPA modification tended to enhance the aggregation of OCZVI particles, while the HDTMA modification reduced the aggregation, and high percentage of modification yielded viscous gel structures. The relatively rapid sedimentation processes in 90 % THF solution (compared to that in 50 % THF solution) and formation gel structures could reduce the access of DBDE to the interlayer reactive nZVIs, and lead to the significant reduction in reaction rate. These results provide important insights to the organo-modification on clays which could alter their orientations and dispersion in organic-water binary solution to achieve the desired reactivity on confined clay surfaces.