Yi Liu , Dengjie Zhong , Yunlan Xu , Haixing Chang , Lin Dong , Zhuofan Han , Jun Li , Nianbing Zhong
{"title":"La/Al双金属-有机骨架-壳聚糖复合材料对水中磷酸盐的吸附研究","authors":"Yi Liu , Dengjie Zhong , Yunlan Xu , Haixing Chang , Lin Dong , Zhuofan Han , Jun Li , Nianbing Zhong","doi":"10.1016/j.jece.2023.110309","DOIUrl":null,"url":null,"abstract":"<div><p><span>The limited metal sites of monometallic MOFs and the high influence of pH limit their adsorption capacity. To solve these problems, La/Al bimetallic MOFs/chitosan composite was prepared by hydrothermal synthesis and impregnation methods and then characterized by XRD, FTIR, SEM, BET and XPS<span> techniques. The doping of La has no obvious effect on the structure of Al-MOFs, but chitosan has greatly changed the structure of La/Al bimetallic MOFs. The phosphate adsorption of the composite was affected by La/Al molar ratio, chitosan/bimetallic MOFs mass ratio, temperature, phosphate initial concentration, adsorbent dosage, pH, and coexisting ions. The optimum molar ratio of La/Al and mass ratio of chitosan/bimetallic MOFs are 0.5:1 and 5.0%, respectively. The addition of La and chitosan can provide additional adsorption active sites, inhibit metal leaching, and enhance the phosphate adsorption performance, stability, and acid-alkali resistance of the composite. Its maximum adsorption capacity was 264.48 mg·g</span></span><sup>−1</sup><span>. Its phosphate removal efficiency is above 90% at pH= 3.0–9.0. The actual phosphorus-containing wastewater with 7.064 mg·L</span><sup>−1</sup> PO<sub>4</sub><sup>3-</sup><span> and initial pH 7.4 can be treated to meet Chinese first-class effluent quality standard. La, Al, amino groups, and hydroxyl groups play an important role in the adsorption process of phosphate. When pH < pH</span><sub>pzc</sub> (4.99), phosphate is adsorbed by electrostatic gravitation between it and protonated positively charged amino and hydroxyl groups on La and Al, while when pH > pH<sub>pzc</sub><span><span>, phosphate is removed by ligand exchange between it and hydroxyl groups on La and Al. A stable, low-cost, and efficient bimetallic MOFs-based phosphate adsorbent was designed and prepared in this paper, and the results can provide reference for researchers in </span>environmental chemical engineering.</span></p></div>","PeriodicalId":15759,"journal":{"name":"Journal of Environmental Chemical Engineering","volume":null,"pages":null},"PeriodicalIF":7.4000,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"3","resultStr":"{\"title\":\"Adsorption of phosphate in water by La/Al bimetallic-organic frameworks-chitosan composite with wide adaptable pH range\",\"authors\":\"Yi Liu , Dengjie Zhong , Yunlan Xu , Haixing Chang , Lin Dong , Zhuofan Han , Jun Li , Nianbing Zhong\",\"doi\":\"10.1016/j.jece.2023.110309\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><p><span>The limited metal sites of monometallic MOFs and the high influence of pH limit their adsorption capacity. To solve these problems, La/Al bimetallic MOFs/chitosan composite was prepared by hydrothermal synthesis and impregnation methods and then characterized by XRD, FTIR, SEM, BET and XPS<span> techniques. The doping of La has no obvious effect on the structure of Al-MOFs, but chitosan has greatly changed the structure of La/Al bimetallic MOFs. The phosphate adsorption of the composite was affected by La/Al molar ratio, chitosan/bimetallic MOFs mass ratio, temperature, phosphate initial concentration, adsorbent dosage, pH, and coexisting ions. The optimum molar ratio of La/Al and mass ratio of chitosan/bimetallic MOFs are 0.5:1 and 5.0%, respectively. The addition of La and chitosan can provide additional adsorption active sites, inhibit metal leaching, and enhance the phosphate adsorption performance, stability, and acid-alkali resistance of the composite. Its maximum adsorption capacity was 264.48 mg·g</span></span><sup>−1</sup><span>. Its phosphate removal efficiency is above 90% at pH= 3.0–9.0. The actual phosphorus-containing wastewater with 7.064 mg·L</span><sup>−1</sup> PO<sub>4</sub><sup>3-</sup><span> and initial pH 7.4 can be treated to meet Chinese first-class effluent quality standard. La, Al, amino groups, and hydroxyl groups play an important role in the adsorption process of phosphate. When pH < pH</span><sub>pzc</sub> (4.99), phosphate is adsorbed by electrostatic gravitation between it and protonated positively charged amino and hydroxyl groups on La and Al, while when pH > pH<sub>pzc</sub><span><span>, phosphate is removed by ligand exchange between it and hydroxyl groups on La and Al. A stable, low-cost, and efficient bimetallic MOFs-based phosphate adsorbent was designed and prepared in this paper, and the results can provide reference for researchers in </span>environmental chemical engineering.</span></p></div>\",\"PeriodicalId\":15759,\"journal\":{\"name\":\"Journal of Environmental Chemical Engineering\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":7.4000,\"publicationDate\":\"2023-10-01\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"3\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Journal of Environmental Chemical Engineering\",\"FirstCategoryId\":\"5\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S2213343723010485\",\"RegionNum\":2,\"RegionCategory\":\"工程技术\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"ENGINEERING, CHEMICAL\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Environmental Chemical Engineering","FirstCategoryId":"5","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S2213343723010485","RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"ENGINEERING, CHEMICAL","Score":null,"Total":0}
Adsorption of phosphate in water by La/Al bimetallic-organic frameworks-chitosan composite with wide adaptable pH range
The limited metal sites of monometallic MOFs and the high influence of pH limit their adsorption capacity. To solve these problems, La/Al bimetallic MOFs/chitosan composite was prepared by hydrothermal synthesis and impregnation methods and then characterized by XRD, FTIR, SEM, BET and XPS techniques. The doping of La has no obvious effect on the structure of Al-MOFs, but chitosan has greatly changed the structure of La/Al bimetallic MOFs. The phosphate adsorption of the composite was affected by La/Al molar ratio, chitosan/bimetallic MOFs mass ratio, temperature, phosphate initial concentration, adsorbent dosage, pH, and coexisting ions. The optimum molar ratio of La/Al and mass ratio of chitosan/bimetallic MOFs are 0.5:1 and 5.0%, respectively. The addition of La and chitosan can provide additional adsorption active sites, inhibit metal leaching, and enhance the phosphate adsorption performance, stability, and acid-alkali resistance of the composite. Its maximum adsorption capacity was 264.48 mg·g−1. Its phosphate removal efficiency is above 90% at pH= 3.0–9.0. The actual phosphorus-containing wastewater with 7.064 mg·L−1 PO43- and initial pH 7.4 can be treated to meet Chinese first-class effluent quality standard. La, Al, amino groups, and hydroxyl groups play an important role in the adsorption process of phosphate. When pH < pHpzc (4.99), phosphate is adsorbed by electrostatic gravitation between it and protonated positively charged amino and hydroxyl groups on La and Al, while when pH > pHpzc, phosphate is removed by ligand exchange between it and hydroxyl groups on La and Al. A stable, low-cost, and efficient bimetallic MOFs-based phosphate adsorbent was designed and prepared in this paper, and the results can provide reference for researchers in environmental chemical engineering.
期刊介绍:
The Journal of Environmental Chemical Engineering (JECE) serves as a platform for the dissemination of original and innovative research focusing on the advancement of environmentally-friendly, sustainable technologies. JECE emphasizes the transition towards a carbon-neutral circular economy and a self-sufficient bio-based economy. Topics covered include soil, water, wastewater, and air decontamination; pollution monitoring, prevention, and control; advanced analytics, sensors, impact and risk assessment methodologies in environmental chemical engineering; resource recovery (water, nutrients, materials, energy); industrial ecology; valorization of waste streams; waste management (including e-waste); climate-water-energy-food nexus; novel materials for environmental, chemical, and energy applications; sustainability and environmental safety; water digitalization, water data science, and machine learning; process integration and intensification; recent developments in green chemistry for synthesis, catalysis, and energy; and original research on contaminants of emerging concern, persistent chemicals, and priority substances, including microplastics, nanoplastics, nanomaterials, micropollutants, antimicrobial resistance genes, and emerging pathogens (viruses, bacteria, parasites) of environmental significance.