Abstract:
The study of the structural features affecting the adsorption of organics, especially contaminants of emerging concern (CECs), onto TiO2 P25 in aqueous medium has far-reaching implications for the understanding and modification of TiO2 P25 in the roles such as an adsorbent and photocatalyst. The effect of pH and γ(TiO2 P25) as variables on the extent of removal of organics by adsorption on TiO2 P25 was investigated by response surface methodology (RSM) and quantitative structure-property relationship (QSPR) modeling. Experimentally determined coefficients of adsorption were used as responses in RSM, yielding a quadratic polynomial equation (QPE) for each of the studied organics. Furthermore, coefficients (A, B, C, D, E, and F) obtained from QPEs were used as responses in QSPR modeling to establish their dependence on the structural features of the studied organics. The functional stability and predictive power of the resulting QSPR models were confirmed with internal and external cross validation. The influence of structural features of organics on the adsorption process is explained by molecular descriptors included in the derived QSPR models. The most influential descriptors on the adsorption of organics on TiO2 P25 are found to be those correlated with ionization potential, molecular mass, and volume, then molecular fragments (e.g., -CH =) and particular topological features such as C and N atoms, or two heteroatoms (e.g., N and N or O and Cl) at certain distance. Derived QSPR models can be considered as robust predictive tools for evaluating efficiency of adsorption processes onto TiO2 P25, providing insights into influential structural features facilitating adsorption process.
摘要:
影响有机物吸附的结构特征的研究,特别是新兴关注的污染物(CEC),在水性介质中加入TiO2P25对于理解和修饰TiO2P25在吸附剂和光催化剂等方面的作用具有深远的意义。通过响应面法(RSM)和定量结构-性质关系(QSPR)模型研究了pH和γ(TiO2P25)作为变量对TiO2P25吸附有机物去除程度的影响。实验确定的吸附系数被用作RSM中的响应,为每个研究的有机物生成二次多项式方程(QPE)。此外,系数(A,B,C,D,E,从QPE获得的F)用作QSPR建模中的响应,以确定它们对所研究有机物结构特征的依赖性。通过内部和外部交叉验证证实了所得QSPR模型的功能稳定性和预测能力。有机物结构特征对吸附过程的影响由衍生的QSPR模型中包含的分子描述符解释。发现对TiO2P25上有机物吸附最有影响的描述符是与电离势相关的描述符,分子量,和音量,然后分子片段(例如,-CH=)和特定的拓扑特征,例如C和N原子,或两个杂原子(例如,一定距离的N和N或O和Cl)。衍生的QSPR模型可以被认为是评估TiO2P25吸附过程效率的强大预测工具,为促进吸附过程的有影响力的结构特征提供见解。