乙酸改性γ-Al2O3高效去除痕量PCl3的研究
Study on the efficient removal of trace PCl3 by acetic acid-modified γ-Al2O3
黄鹏兵 1袁威 1王雪莹 1王悦 1张建树 1邓人攀1
作者信息
- 1. 石河子大学化学化工学院/化工绿色过程省部共建国家重点实验室培育基地,新疆 石河子 832003
- 折叠
摘要
在多晶硅生产过程中,为了不影响产品性能,必须将杂质PCl3 的含量降低到ppb的水平,然而,这目前仍旧是一个巨大的挑战.本研究提出了一种可高效去除痕量 PC13 的方法,即利用乙酸改性 γ-Al2O3 作为吸附剂,其可去除 ppb级别的 PC13,去除率高达 84.2%.Boehm滴定实验表明,改性后的 γ-Al2O3 表面羧基含量大幅增加,从而增加了吸附PCl3 的活性位点,使其对PCl3 的吸附性能显著提升.表征分析和DFT模拟计算表明,乙酸与γ-Al2O3 主要是通过 γ-Al2O3 中的羟基 H和乙酸中的羰基 O 形成氢键而相互作用的;除了物理吸附外,γ-Al2O3 中的 Al 与PCl3 中的Cl,以及乙酸中的羰基O与PCl3 中的P 之间还可通过电荷转移相互作用.连续五次循环实验表明,该吸附剂在低温下具有优异的再生性能.本研究开发的吸附剂由于其高效、易于再生和低成本等特点,在去除痕量PCl3 方面具有潜在的应用前景.
Abstract
It is necessary to reduce the amount of PCl3 to ppb levels during polysilicon production in order not to affect product perform-ance.However,the removal of PCl3 impurities to the ppb levels remains a big challenge.In this work,we present a highly effective adsorbent for the efficient removal of trace PCl3,that is,acetic acid modified γ-Al2O3,which can remove PC13 at ppb levels with a removal rate of up to 84.2%.The Boehm titration experiments revealed a substantial increase in the carboxyl group content on the sur-face of γ-Al2O3 after modification,thereby facilitating an augmented number of adsorption sites for PCl3 and consequently enhancing its removal efficiency.By means of characterization analysis and DFT simulations,it is suggested that the predominant interaction between acetic acid and γ-Al2O3 occurs through the establishment of hydrogen bonds between the hydroxyl H of acetic acid and O in Al2O3.In addition to simple physical adsorption,it has been found that the interaction by charge transfer between Al in γ-Al2O3 and Cl in PCl3,as well as between carbonyl oxygen in acetic acid and P in PCl3,play a significant role in enhancing the removal of PCl3.Five consec-utive cycle experiments show that the adsorbent has excellent regeneration properties at low regeneration temperature.The adsorbent de-veloped in this work is promising for applications in the removal of trace amounts of PCl3 due to its efficiency,ease of regeneration and low cost.
关键词
γ-Al2O3/乙酸/吸附/痕量PCl3/多晶硅Key words
γ-Al2O3/acetic acid/adsorption/trace PCl3/polysilicon引用本文复制引用
出版年
2024
NETL
NSTL
万方数据