{"title":"Adsorption of Phenols from Aqueous Solution with A pH-Sensitive Surfactant-Modified Bentonite","authors":"Xiangfen Cui, Jingmei Liao, Huaying Liu, Wei Tang, Cheng Tie, Senlin Tian, Yingjie Li","doi":"10.3390/separations10100523","DOIUrl":null,"url":null,"abstract":"The presence of organic pollutants in wastewater remains a prominent environmental concern due to the related ecological and health hazards. In response, this study employs an adsorptive methodology to address the removal of phenol and catechol, utilizing an organo-bentonite material modified with a pH-responsive switchable surfactant, dodecyldimethylamine oxide (C12DAO). The synthesized organo-bentonite (C12DAO-Bt) manifests commendable thermostability resulting from thermogravimetric analyses. The adsorption capacities of C12DAO-Bt concerning phenol and catechol intensify with the augmentation of the C12DAO/bentonite mass ratio. The utmost adsorption capacities of 150C12DAO-Bt, deduced through a pseudo-second-order kinetic model, stand at 5.72 mg·g−1 for phenol and 5.55 mg·g−1 for catechol, respectively. Subject to modification by a pH-responsive surfactant, conditions leaning towards weakly acidic and neutral conditions (pH = 6~7) are conducive to the adsorption of phenolic compounds. Conversely, alkaline conditions (pH = 8~9) facilitate the dissociation of adsorbates from adsorbents. The augmentation of cationic strength within the examined scope incites the adsorption procedure while impeding the desorption efficacy. In the case of cationic species with comparable ionic strengths, Na+ exhibited a superior effect on the adsorption–desorption dynamics of phenol, while Ca2+ exerts a more pronounced effect on those of catechol. Moreover, even following five consecutive acid–base regulation cycles, C12DAO-Bt retains a relatively high adsorption capacity and desorption efficacy, which underscores its exceptional regenerative capacity for removing phenolic compounds from wastewater.","PeriodicalId":21833,"journal":{"name":"Separations","volume":"331 1","pages":"0"},"PeriodicalIF":2.5000,"publicationDate":"2023-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Separations","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.3390/separations10100523","RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"CHEMISTRY, ANALYTICAL","Score":null,"Total":0}
引用次数: 0
Abstract
The presence of organic pollutants in wastewater remains a prominent environmental concern due to the related ecological and health hazards. In response, this study employs an adsorptive methodology to address the removal of phenol and catechol, utilizing an organo-bentonite material modified with a pH-responsive switchable surfactant, dodecyldimethylamine oxide (C12DAO). The synthesized organo-bentonite (C12DAO-Bt) manifests commendable thermostability resulting from thermogravimetric analyses. The adsorption capacities of C12DAO-Bt concerning phenol and catechol intensify with the augmentation of the C12DAO/bentonite mass ratio. The utmost adsorption capacities of 150C12DAO-Bt, deduced through a pseudo-second-order kinetic model, stand at 5.72 mg·g−1 for phenol and 5.55 mg·g−1 for catechol, respectively. Subject to modification by a pH-responsive surfactant, conditions leaning towards weakly acidic and neutral conditions (pH = 6~7) are conducive to the adsorption of phenolic compounds. Conversely, alkaline conditions (pH = 8~9) facilitate the dissociation of adsorbates from adsorbents. The augmentation of cationic strength within the examined scope incites the adsorption procedure while impeding the desorption efficacy. In the case of cationic species with comparable ionic strengths, Na+ exhibited a superior effect on the adsorption–desorption dynamics of phenol, while Ca2+ exerts a more pronounced effect on those of catechol. Moreover, even following five consecutive acid–base regulation cycles, C12DAO-Bt retains a relatively high adsorption capacity and desorption efficacy, which underscores its exceptional regenerative capacity for removing phenolic compounds from wastewater.
期刊介绍:
Separations (formerly Chromatography, ISSN 2227-9075, CODEN: CHROBV) provides an advanced forum for separation and purification science and technology in all areas of chemical, biological and physical science. It publishes reviews, regular research papers and communications. Our aim is to encourage scientists to publish their experimental and theoretical results in as much detail as possible. There is no restriction on the length of the papers. The full experimental details must be provided so that the results can be reproduced. There are, in addition, unique features of this journal:
Manuscripts regarding research proposals and research ideas will be particularly welcomed.
Electronic files and software regarding the full details of the calculation and experimental procedure, if unable to be published in a normal way, can be deposited as supplementary material.
Manuscripts concerning summaries and surveys on research cooperation and projects (that are funded by national governments) to give information for a broad field of users.
The scope of the journal includes but is not limited to:
Theory and methodology (theory of separation methods, sample preparation, instrumental and column developments, new separation methodologies, etc.)
Equipment and techniques, novel hyphenated analytical solutions (significantly extended by their combination with spectroscopic methods and in particular, mass spectrometry)
Novel analysis approaches and applications to solve analytical challenges which utilize chromatographic separations as a key step in the overall solution
Computational modelling of separations for the purpose of fundamental understanding and/or chromatographic optimization