Highly efficient,low-cost,and portable wastewater treatment and purification solutions are urgently needed for aqueous pollution removal,especially at remote sites.Synergistic photocatalytic (PC) and persulphate (PS) ...Highly efficient,low-cost,and portable wastewater treatment and purification solutions are urgently needed for aqueous pollution removal,especially at remote sites.Synergistic photocatalytic (PC) and persulphate (PS) degradation under visible light offers an exceptional alternative for this purpose.In this work,we coupled a TiO^(2-)based PC system with a PS oxidation system into a portable advanced oxidation device for rapid and deep degradation of organic contaminants in wastewater.Using hydrogenation,we fabricated hydrogenated anatase branched-rutile TiO_(2) nanorod (H-AB@RTNR) photocatalysts which enable the PC degradation to occur under visible light and improve the utilization of solar energy.We also discovered that the addition of PS resulted in the synergistic degradation of tenacious and persistent organics,dramatically improving the extent and kinetics of the degradation.A degradation rate of 100%and a reaction rate constant of 0.0221 min^(-1)for degrading 1 L rhodamine B(20 mg L^(-1)) were achieved in 120 min in a specially designed thin-layer cell under visible light irradiation.The superior performance of the synergistic PC and PS degradation system was also demonstrated in the degradation of real industrial wastewater.Both remarkable performances can be attributed to the heterophase junction and oxygen vacancies in the photocatalyst that facilitate the catalytic conversion of PS anions into highly active radicals (·SO_(4)-and·OH).This work suggests that the as-proposed synergistic degradation design is a promising solution for building a portable wastewater treatment system.展开更多
文摘本研究对磺胺二甲基嘧啶(SMT)在不同条件下的辐照降解进行了研究.SMT(20 mg·L^(-1),约0.072 mmol·L^(-1))在外加过硫酸根浓度为0、1、2、4、10和20 mmol·L^(-1)条件下分别进行辐照,发现伽马辐照可有效去除水中的SMT,并可极大地促进溶液TOC的去除,过硫酸盐与伽马辐照联合作用表现出明显的协同效应.在本研究中,各条件下的辐照降解反应均符合准一级反应动力学.在外加过硫酸盐的条件下,溶液的矿化度可以得到极大的提高,当吸收剂量为1 k Gy时,其矿化度由3.5%提高到22.8%,当吸收剂量为5 k Gy时,矿化度由14.1%提高到70.1%.在辐解后的溶液中,利用IC检测到硫酸根离子(SO_4^(2-))、甲酸根离子(HCOO^-)和乙酸根离子(CH_3COO^-)3种离子的存在,一部分中间产物通过GC-MS检测得到,常见的含氮离子(NO_2^-、NO_3^-和NH_4^++)并未在溶液中检测到.同时,本研究还深入探讨了SMT辐照降解机理和降解途径.
基金supported by Griffith University PhD scholarshipsthe National Natural Science Foundation of China (22078118)the Natural Science Foundation of Guangdong Province (2019A1515011138)。
文摘Highly efficient,low-cost,and portable wastewater treatment and purification solutions are urgently needed for aqueous pollution removal,especially at remote sites.Synergistic photocatalytic (PC) and persulphate (PS) degradation under visible light offers an exceptional alternative for this purpose.In this work,we coupled a TiO^(2-)based PC system with a PS oxidation system into a portable advanced oxidation device for rapid and deep degradation of organic contaminants in wastewater.Using hydrogenation,we fabricated hydrogenated anatase branched-rutile TiO_(2) nanorod (H-AB@RTNR) photocatalysts which enable the PC degradation to occur under visible light and improve the utilization of solar energy.We also discovered that the addition of PS resulted in the synergistic degradation of tenacious and persistent organics,dramatically improving the extent and kinetics of the degradation.A degradation rate of 100%and a reaction rate constant of 0.0221 min^(-1)for degrading 1 L rhodamine B(20 mg L^(-1)) were achieved in 120 min in a specially designed thin-layer cell under visible light irradiation.The superior performance of the synergistic PC and PS degradation system was also demonstrated in the degradation of real industrial wastewater.Both remarkable performances can be attributed to the heterophase junction and oxygen vacancies in the photocatalyst that facilitate the catalytic conversion of PS anions into highly active radicals (·SO_(4)-and·OH).This work suggests that the as-proposed synergistic degradation design is a promising solution for building a portable wastewater treatment system.
