Adsorption isotherms of some heavy metals under conditions of their competitive adsorption onto highly calcareous soils of southern Iran

The potential impact of the addition of sewage sludge from domestic waste water treatment plants on agricultural soils is a worldwide concern. A proportion of heavy metals in sewage sludge will be present in the soil solution; their equilibria can be modified by the competitive interactions between them, changing not only their mobility but also their adsorption pattern. The competitive adsorption of heavy metals by soils has been studied by several authors in simple model substrates and synthetic minerals, and also in soils but restricted to binary adsorption. In the present paper the modification of the Cu, Pb, Ni, and Zn interactions with soils as a consequence of a competitive adsorption on the available adsorption sites on Andisols were determined.The single- and multi-component adsorption of Cu, Pb, Ni, and Zn were carried out at constant ionic strength (0.1 m KNO3). The adsorption was monitored by ICP-OES and the Langmuir model was applied to fit the adsorption isotherms.Competitive adsorption isotherms indicate a reduction of the adsorption in the control soils when compared to the single adsorption isotherms. The maximum adsorption constants for single- and multi-component isotherms for Diguillín soil were 38.2 and 33.3 mmol/kg for Cu, 48.1 and 30.0 mmol/kg for Pb, 5.4 and 2.1 mmol/kg for Ni, and 18.0 and 8.1 mmol/kg for Zinc, respectively. With Ralun soil, lower values were obtained, but the same tendency was observed.The maximum adsorption and the affinity constant increased for all cations, after the addition of sewage sludge to Diguillin soil.

Download Full-text

Utilisation of Biomass and Hybrid Biochar from Elephant Grass and Low Density Polyethylene for the Competitive Adsorption of Pb(II), Cu(II), Fe(II) and Zn(II) from Aqueous Media

Recent Innovations in Chemical Engineering (Formerly Recent Patents on Chemical Engineering) ◽

10.2174/2405520413999201117143926 ◽

2020 ◽

Vol 13 ◽

Author(s):

Joshua O. Ighalo ◽

Lois T. Arowoyele ◽

Samuel Ogunniyi ◽

Comfort A. Adeyanju ◽

Folasade M. Oladipo-Emmanuel ◽

...

Keyword(s):

Heavy Metals ◽

Removal Efficiency ◽

Contact Time ◽

Competitive Adsorption ◽

Adsorption Process ◽

Aqueous Media ◽

Polluted Water ◽

Batch Adsorption ◽

Order Kinetic ◽

Elephant Grass

Background: The presence of pollutants in polluted water is not singularized hence pollutant species are constantly in competition for active sites during the adsorption process. A key advantage of competitive adsorption studies is that it informs on the adsorbent performance in real water treatment applications. Objective: This study aims to investigate the competitive adsorption of Pb(II), Cu(II), Fe(II) and Zn(II) using elephant grass (Pennisetum purpureum) biochar and hybrid biochar from LDPE. Method: The produced biochar was characterised by Scanning Electron Microscopy (SEM) and Fourier Transform Infrared Spectroscopy (FTIR). The effect of adsorption parameters, equilibrium isotherm modelling and parametric studies were conducted based on data from the batch adsorption experiments. Results: For both adsorbents, the removal efficiency was >99% over the domain of the entire investigation for dosage and contact time suggesting that they are very efficient for removing multiple heavy metals from aqueous media. It was observed that removal efficiency was optimal at 2 g/l dosage and contact time of 20 minutes for both adsorbent types. The Elovich isotherm and the pseudo-second order kinetic models were best-fit for the competitive adsorption process. Conclusion: The study was able to successfully reveal that biomass biochar from elephant grass and hybrid biochar from LDPE can be used as effective adsorbent material for the removal of heavy metals from aqueous media. This study bears a positive implication for environmental protection and solid waste management.

Download Full-text

Factors Affecting Potassium Pools Distribution in Calcareous Soils of Southern Iran

Arid Land Research and Management ◽

10.1080/15324982.2011.602177 ◽

2011 ◽

Vol 25 (4) ◽

pp. 313-327 ◽

Cited By ~ 12

Author(s):

Mahdi Najafi Ghiri ◽

Ali Abtahi ◽

Hamidreza Owliaie ◽

Soheila Sadat Hashemi ◽

Hadi Koohkan

Keyword(s):

Calcareous Soils ◽

Factors Affecting ◽

Southern Iran

Download Full-text

Aflatoxin B1 and heavy metals in imported black tea to Bushehr, southern Iran; Contamination rate and risk assessment

Journal of Food Composition and Analysis ◽

10.1016/j.jfca.2021.104277 ◽

2021 ◽

pp. 104277

Author(s):

Esmaeel Abbasi ◽

Mohammad Hashem Yousefi ◽

Seyedenayat Hashemi ◽

Saeid Hosseinzadeh ◽

Amir Hossein Ghadimi ◽

...

Keyword(s):

Heavy Metals ◽

Risk Assessment ◽

Aflatoxin B1 ◽

Black Tea ◽

Contamination Rate ◽

Southern Iran

Download Full-text

Separation of Cd(ii) and Ni(ii) in a binary mixture through competitive adsorption and acid leaching

RSC Advances ◽

10.1039/c5ra13789f ◽

2015 ◽

Vol 5 (113) ◽

pp. 92885-92892 ◽

Cited By ~ 4

Author(s):

Hong Guo ◽

Shufen Zhang ◽

Zinong Kou ◽

Shangru Zhai ◽

Wei Ma ◽

...

Keyword(s):

Heavy Metals ◽

Binary Mixture ◽

Aqueous Solutions ◽

Environmental Protection ◽

Competitive Adsorption ◽

Acid Leaching

Different heavy metals present simultaneously in aqueous solutions should be separated to promote environmental protection.

Download Full-text

Kinetics comparison on simultaneous and sequential competitive adsorption of heavy metals in red soils

Journal of Central South University ◽

10.1007/s11771-015-2643-2 ◽

2015 ◽

Vol 22 (4) ◽

pp. 1269-1275 ◽

Cited By ~ 5

Author(s):

Yan Wang ◽

Zhong-wu Li ◽

Bin Huang ◽

Wei-guo Jiang ◽

Liang Guo ◽

...

Keyword(s):

Heavy Metals ◽

Competitive Adsorption ◽

Red Soils

Download Full-text

Adsorption properties of CH4 and CO2 in quartz nanopores studied by molecular simulation

RSC Advances ◽

10.1039/c6ra05083b ◽

2016 ◽

Vol 6 (39) ◽

pp. 32770-32778 ◽

Cited By ~ 19

Author(s):

Haoyang Sun ◽

Wenchao Sun ◽

Hui Zhao ◽

Yange Sun ◽

Dianrui Zhang ◽

...

Keyword(s):

Molecular Simulation ◽

Binary Mixtures ◽

Adsorption Isotherms ◽

Competitive Adsorption ◽

Adsorption Properties ◽

Density Distributions ◽

Adsorption Density ◽

Surface Hydroxylation

Competitive adsorption isotherms and adsorption density distributions of binary mixtures containing CH4 and CO2 in nanopores with 100% and 60% surface hydroxylation at 323 K.

Download Full-text

Study on the Removal of Pb2+, Cu2+, and Cd2+ from Wastewater Using Modified Stilbite

Materials Science Forum ◽

10.4028/www.scientific.net/msf.852.1342 ◽

2016 ◽

Vol 852 ◽

pp. 1342-1348

Author(s):

Xi Chen ◽

Tian Shun Cui ◽

Shuang Zhao ◽

Xiao Jun Deng

Keyword(s):

Heavy Metals ◽

Competitive Adsorption ◽

Adsorption Rate ◽

Isothermal Adsorption ◽

Adsorption Time ◽

Adsorption Characteristics ◽

Static Conditions ◽

The Impact

In this study, we studied the ability of modified Stilbite to adsorb heavy metals Pb2+, Cu2+, and Cd2+ from wastewater. In static conditions, we investigated the impact of pH, temperature, dosage, and the competitive adsorption characteristics of the modified Stilbite in addressing pollution of wastewater with Pb2+, Cu2+, Cd2+. The testing showed that: under normal circumstances, with a pH between 5-6, a dosage of 0.7 g, and an adsorption time of 90 minutes, the adsorption rate of the three metals was above 90%. The adsorption rate of Cu was greater than Pb, which was greater than Cd. The modified Stilbite adsorption of the three metals met Langmuir and Freundlich isothermal adsorption equations. The study also revealed that regenerated Stilbite, after adsorption, can still continue to be used for adsorption of heavy metals.

Download Full-text