{"title":"Adsorption Behavior of Cadmium in Argillaceous Limestone Yellow Soils Simulated by The Surface Complexation Model","authors":"Qin Haoli, Liu Yan, Li Mei, Yang Yang, An Ya","doi":"10.1007/s11270-024-07322-y","DOIUrl":null,"url":null,"abstract":"<p>In the present study, based on continuous acid–base potentiometric titration experiments of argillaceous limestone-derived yellow soil obtained at different depths in Pingba, Guizhou, a 1-site/2-pK<sub><i>a</i></sub> generalized composite surface complexation model (SCM) was established to obtain relevant parameters and explore soil surface acid–base properties. The model was employed to simulate cadmium (Cd) adsorption behavior. Combining the physicochemical properties of yellow soil and acid–base titration curves, the SCM-derived concentrations (<i>H</i><sub><i>s</i></sub>) and densities (<i>D</i><sub><i>s</i></sub>) of the surface-active sites for three soil layers showed decreasing trends with an increase in depth, whereas the calculated soil charge zero point (pH<sub>pzc</sub>) values matched the experimental values, indicating the applicability of SCM in studying the surface acid–base properties of yellow soil. Furthermore, as the pH increased, Cd shifted gradually from the dissolved to the adsorbed state, achieving complete adsorption at a pH of ~ 7. The model-simulated Cd adsorption curve matched well with the experimental curve; the Cd adsorption behavior corresponded with the simulated distribution of surface sites at different pH levels, with ≡SOH<sub>2</sub><sup>+</sup> and ≡SO<sup>−</sup> being the main forms at pH < pH<sub>pzc</sub> and pH > pH<sub>pzc</sub>, respectively. Correlation analysis indicated that organic matter and goethite played a major role in <i>H</i><sub><i>s</i></sub>, whereas the charge zero points of soils at different depths were determined mainly by clay minerals, such as illite and iron-aluminum oxides. Our study established a scientific and reasonable relationship between the soil physicochemical properties and model parameters, providing a basis for preventing heavy metal pollution behavior via the effective application of model predictions.</p>","PeriodicalId":808,"journal":{"name":"Water, Air, & Soil Pollution","volume":null,"pages":null},"PeriodicalIF":3.8000,"publicationDate":"2024-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Water, Air, & Soil Pollution","FirstCategoryId":"6","ListUrlMain":"https://doi.org/10.1007/s11270-024-07322-y","RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"ENVIRONMENTAL SCIENCES","Score":null,"Total":0}
引用次数: 0
Abstract
In the present study, based on continuous acid–base potentiometric titration experiments of argillaceous limestone-derived yellow soil obtained at different depths in Pingba, Guizhou, a 1-site/2-pKa generalized composite surface complexation model (SCM) was established to obtain relevant parameters and explore soil surface acid–base properties. The model was employed to simulate cadmium (Cd) adsorption behavior. Combining the physicochemical properties of yellow soil and acid–base titration curves, the SCM-derived concentrations (Hs) and densities (Ds) of the surface-active sites for three soil layers showed decreasing trends with an increase in depth, whereas the calculated soil charge zero point (pHpzc) values matched the experimental values, indicating the applicability of SCM in studying the surface acid–base properties of yellow soil. Furthermore, as the pH increased, Cd shifted gradually from the dissolved to the adsorbed state, achieving complete adsorption at a pH of ~ 7. The model-simulated Cd adsorption curve matched well with the experimental curve; the Cd adsorption behavior corresponded with the simulated distribution of surface sites at different pH levels, with ≡SOH2+ and ≡SO− being the main forms at pH < pHpzc and pH > pHpzc, respectively. Correlation analysis indicated that organic matter and goethite played a major role in Hs, whereas the charge zero points of soils at different depths were determined mainly by clay minerals, such as illite and iron-aluminum oxides. Our study established a scientific and reasonable relationship between the soil physicochemical properties and model parameters, providing a basis for preventing heavy metal pollution behavior via the effective application of model predictions.
期刊介绍:
Water, Air, & Soil Pollution is an international, interdisciplinary journal on all aspects of pollution and solutions to pollution in the biosphere. This includes chemical, physical and biological processes affecting flora, fauna, water, air and soil in relation to environmental pollution. Because of its scope, the subject areas are diverse and include all aspects of pollution sources, transport, deposition, accumulation, acid precipitation, atmospheric pollution, metals, aquatic pollution including marine pollution and ground water, waste water, pesticides, soil pollution, sewage, sediment pollution, forestry pollution, effects of pollutants on humans, vegetation, fish, aquatic species, micro-organisms, and animals, environmental and molecular toxicology applied to pollution research, biosensors, global and climate change, ecological implications of pollution and pollution models. Water, Air, & Soil Pollution also publishes manuscripts on novel methods used in the study of environmental pollutants, environmental toxicology, environmental biology, novel environmental engineering related to pollution, biodiversity as influenced by pollution, novel environmental biotechnology as applied to pollution (e.g. bioremediation), environmental modelling and biorestoration of polluted environments.
Articles should not be submitted that are of local interest only and do not advance international knowledge in environmental pollution and solutions to pollution. Articles that simply replicate known knowledge or techniques while researching a local pollution problem will normally be rejected without review. Submitted articles must have up-to-date references, employ the correct experimental replication and statistical analysis, where needed and contain a significant contribution to new knowledge. The publishing and editorial team sincerely appreciate your cooperation.
Water, Air, & Soil Pollution publishes research papers; review articles; mini-reviews; and book reviews.