Evaluation of the Influence of Environmental Conditions on the Removal of Pb(II) from Wastewater by Ca-rectorite

The removal of Pb(II) from wastewater by Ca-rectorite was investigated as various environmental factors containing contact time, pH, ionic strength, solid content, coexisting ions, humic acid (HA), and temperature. The kinetic sorption of Pb(II) on Ca-rectorite was well described by the pseudo second-order model. The sorption process was strongly dependent on pH and ionic strength. The results indicated that the presence of HA and coexisting ions influenced the sorption of Pb(II) on Ca-rectorite obviously. Besides, the Langmuir and Freundlich models were employed to simulate the sorption isotherms. The thermodynamic parameters indicated that the sorption process was spontaneous and endothermic. It is possible to conclude that Ca-rectorite has a good potential for disposal of lead-contaminated wastewater.     

Sorption of Pb(II), Cd(II) and Zn(II) by iminodiacetate chelating resins in non-competitive and competitive conditions

Two chelating resins (CRs) bearing iminodiacetate (IDA) groups derived from acrylonitrile - divinylbenzene (AN-DVB) copolymers having 10 and 15 wt.% nominal cross-linking degrees and a high mobility of the functional groups caused by the presence of a longer spacer between the matrix and the IDA groups were synthesized and tested as sorbents for heavy metal ions like: Pb(II), Cd(II) and Zn(II) from aqueous solutions by batch and column techniques. Experimental data obtained from batch equilibrium tests have been analyzed by two isotherm models: Freundlich and Langmuir. The overall adsorption tendency of CRs toward Pb(II), Cd(II) and Zn(II), under non-competitive conditions, followed the order: Cd(II) > Pb(II) > Zn(II). Selectivity studies were performed in ternary mixture of Pb(II), Cd(II) and Zn(II) to check if the synthesized CRs can be useful for selective separation of heavy metal cations. The results revealed that the CRs with IDA groups exhibited high selectivity toward Pb(II), both in batch and column techniques. Regeneration of the resins was achieved using 0.1 M HCl solution.     

Reciprocal effect of Pb(II) and surfactant onto their sorption in weak acid polyacrylic cation exchanger

The decrease in the equilibrium sorption of Pb(II) and nonionic surfactants (oxyethylated alcohols OS-20 and alkylmonoethers ALM-10) in H-form of Purolite C 106 cation exchanger was observed due to their presence in the same solution. The sorption of Pb(II) both in the form of free cations and in the form of Pb(II) bonded with surfactant takes place. The sorption of Pb(II) bonded with OS-20 is higher compared with that of Pb(II) bonded with ALM-10. In the presence of ALM-10 the sorption of Pb(II) free cations prevails. Increasing the acidity from pH 5 to pH 3, increases the rate of the sorption of surfactant. Due to the presence of surfactant the rate of Pb(II) sorption also increases, while without surfactant it decreases with an increase in acidity. © 1998 SCI     

Adsorption of Pb(II) Ions Using Humic Acid Coated Chitosan-Tripolyphosphate (HA-CTPP) Beads

A new humic acid (HA) based adsorbent was prepared by coating humic acid on chitosan tripolyphosphate (CTPP) beads. Humic acid-chitosan tripolyphosphate (HA-CTPP) beads thus obtained were characterized using Fourier Transform Infrared Spectroscopy and Scanning Electron Microscopy. Swelling capacity studies of CTPP and HA-CTPP beads conducted in the pH range, pH = 1–10 showed that HA-CTPP beads are more stable against swelling than CTPP beads. Equilibration of HA-CTPP beads in water for different pH showed that leaching of HA from the beads is negligible and the beads are stable for adsorption applications. Adsorption of Pb(II) ions onto HA-CTPP beads were studied as a function of various operational parameters such as initial pH, metal ion concentration, and contact time. The results showed that HA-CTPP beads are suitable for Pb(II) ions adsorption and the kinetics of sorption very well fit into pseudo-second order model. The Langmuir model was found to be more suitable for explaining the observed adsorption data, giving a theoretical maximum adsorption capacity of 223.7 mg/g. HA-CTPP beads could possibly find application in the treatment of waste water contaminated with other toxic and/or heavy metals.     

Sorptive removal of Pb(II) ions from aqueous solution using sweetmeat waste: Batch and column study

This article deals with removal of Pb(II) ions from aqueous media using sweet industry byproduct, that is, sweetmeat waste (SMW). The SEM images revealed highly heterogeneous sorbent surface. XRD and FTIR studies were done. The sorption equilibrium time was found 45 min only, and the sorption followed pseudo-second-order reaction model, indicating chemisorption as the rate-limiting step. Pb(II) removal followed Langmuir isotherm model best, and the maximum sorption capacity was 11.38 mg/g. The fixed bed column study was performed and analyzed using Logit, Bohart-Adams and Wolborska models. The sorption rate and capacity constants were 0.143(±0.017) L/mg.h and 39(±7) mg/L, respectively.     

Kinetic and Equilibrium Modeling of Pb(II) and Co(II) Sorption onto Rose Waste Biomass

Abstract

An attempt was made to assess the biosorption potential of rose waste biomass for the removal of Pb(II) and Co(II) ions from synthetic effluents. Biosorption of heavy metal ions (>90%) reached equilibrium in 30 min. Maximum removal of Pb(II) and Co(II) occurred at pH 5 and 6 respectively. The biosorbent dose for efficient uptake of Pb(II) and Co(II) was 0.5 g/L for both metals. The biosorbent size affected the Pb(II) and Co(II) biosorption rate and capacity. Rose waste biomass was found effective for Pb(II) and Co(II) removal from synthetic effluents in the concentration range 10–640 mg/L. Equilibrium sorption studies showed that the extent of Pb(II) and Co(II) uptake by the rose waste biomass was better described by the Langmuir isotherm in comparison to the Freundlich model. The uptake capacities of the two metal ions were 156 and 27.15 mg/g for Pb(II) and Co(II) respectively.     

Kinetic and equilibrium studies of Pb(II) and Cd(II) removal from aqueous solution onto colemanite ore waste

The adsorption characteristics of Pb(II) and Cd(II) onto colemanite ore waste (CW) from aqueous solution were investigated as a function of pH, adsorbent dosage, contact time, and temperature. Langmuir, Freundlich and Dubinin-Radushkevich (D-R) models were applied to describe the adsorption isotherms. Langmuir model fitted the equilibrium data better than the Freundlich isotherm. The adsorption capacity of CW was found to be 33.6 mg/g and 29.7 mg/g for Pb(II) and Cd(II) ions, respectively. Analyte ions were desorbed from CW using both 1 M HCl and 1 M HNO₃. The recovery for both metal ions was found to be higher than 95%. The mean adsorption energies evaluated using the D-R model indicated that the adsorption of Pb(II) and Cd(II) onto CW were taken place by chemisorption. The thermodynamic parameters (ΔG^o, ΔH^o and ΔS^o) showed that the adsorption of both metal ions was feasible, spontaneous and exothermic at 20-50 °C. Adsorption mechanisms were also investigated using the pseudo-first-order and pseudo-second-order kinetic models. The kinetic results showed that the adsorption of Pb(II) and Cd(II) onto CW followed well pseudo-second order kinetics.     

Fast removal of Pb(II) and Cu(II) from contaminated water by groundwater treatment waste: impact of sorbent composition

ABSTRACT

A non-hazardous groundwater treatment waste (GWTW) was examined as a low-cost sorbent for Pb(II) and Cu(II) ions. The content of the dominant elements in GWTW was as follows: 78% Fe₂O₃, 7.4% P₂O₅, 7.4% CaO and 5.2% SiO₂. The removal of Pb(II) and Cu(II) was fast, and more than 67–95% of ions were accumulated by GWTW during the first 3 min. The sorption capacity of GWTW depends on solution pH, concentration and temperature. Equilibrium data fitted well with Langmuir–Freundlich and Langmuir-partition models. The inherently formed nano-adsorbent could be utilized for the treatment of water contaminated with Pb(II) and Cu(II) ions.     

Efficient removal of Cr(VI) and Pb(II) from aqueous solution by magnetic nitrogen-doped carbon

The magnetic nitrogen-doped carbon (MNC) was prepared from polypyrrole by a simple high temperature calcination process in this paper. The structure and properties of MNC were analyzed by scanning electron microscope, Fourier transform infrared spectroscopy, X-ray diffraction, Brunner-Emmet-Teller, vibrating sample magnetometer, and X-ray photoelectron spectroscopy. The capacity of MNC to adsorb Cr(VI) and Pb(II) was evaluated. The effects of the initial pH, dosage, concentration and temperature on the adsorption capacity of MNC were measured. MNC had a large specific surface area and a special porous structure. Its nitrogen and carbon sources were rich, and the ratio of carbon to nitrogen was fixed. The maximum Cr(VI)-adsorption capacity and maximum Pb(II) adsorption capacity of MNC could reach 456.63 and 507.13 mg∙g⁻¹ at 318 K, respectively. The pseudo-second-order model was used to describe the adsorption kinetics of MNC, and the Freundlich model was employed to discuss its isotherms. The adsorption process was affected by the electrostatic force, the reducing reaction, pores and chelation. The results of this study suggest that MNC is a material with superior performance, and is very easily regenerated, reused, and separated in the adsorption process.     

Exploitation of Beach Sand as a Low Cost Sorbent for the Removal of Pb(II) Ions from Aqueous Solutions

Abstract

Beach sand is used to remove traces of Pb(II) ions from aqueous solutions. Effect of shaking speed, amount of sorbent, shaking time, nature and concentration of different electrolytes and deionized water along with buffer of pH 2–10 Apak, R., Guclu, K. and Turgut, M. H. 1998. Modeling of copper(II), cadmium(II), and lead(II) adsorption on red mud. J. Colloid Interface Sci., 203: 122 Ma, Y. Q., Traina, S. J., Logen, T. J. and Rayan, J. A. 1994. Effect of aqueous Al, Cd, Cu, Fe, Ni, and Zn on Pb immobilization by hydroxyapatite. Environ. Sci. Technol., 28: 1219 Zhang, P. and Ryan, J. A. 1998. Formation of pyronorphite in analgesite‐hydroxiapatite suspension under varying pH conditions. Environ. Sci. Technol., 32: 3318 Marcantonio, F., Flower, G., Thien, L. and Ellgaard, E. 1998. Pb isotopes in tree rings chronology of pollution in BayouTrepagnier; Louesiana. Environ. Sci. Technol., 32: 2371 Klaassen, C. D. 2001. Casarett and Doull's Toxicology: the basic science of poisons, 6th Ed. Edited by: Klaassen, C. D. New York: McGraw Hill. Plunkett, E. R. 1987. Handbook of Industrial Toxicology USA: Edward Arnold Publication Co; Inc. Hasany, S. M. 2000. Inorganic ion‐exchangers for the treatment and disposal of industrial effluents. The Nucleus, 37: 187 (and references therein) Hasany, S. M., Ahmed, R. and Chaudhary, M. H. 2003. Investigation of sorption of Hg(II) ions onto coconut husk from aqueous solution using radiotracer technique. Radiochim. Acta., 91: 533 (and reference therein) Hasany, S. M., Saeed, M. M. and Ahmed, M. 2003. Sorption of traces of silver ions onto polyurethane foam from acidic solution. Talanta, 54: 89 (and reference therein)  have been studied. Maximum sorption of Pb(II) ions (>94%) is achieved from 10^?4M HNO₃. Sorption data have been tested using Langmuir, Freundlich, and Dubinin‐Radushkevich (D‐R) sorption isotherms. Thermodynamic parameters such as ΔH, ΔS, and ΔG have been evaluated. Kinetics of sorption is followed by Morris‐ Weber, Reichenberg and Lagergren equations. Influence of diverse ions on the sorption of Pb(II) ions is also investigated.     

Pb(II) biosorption using DAP/EDTA-modified biopolymer (Chitosan)

Abstract

In this study, chitosan was chemically modified with only diammonium phosphate (DAP) and DAP/EDTA (ethylenediaminetetraacetic acid) mixture for the removal of Pb(II) ions from aqueous solution. Modified chitosan forms were analyzed using thermo-gravimetric analyzer (TGA), Fourier transform infrared (FTIR) spectroscopy, and scanning electron microscopy (SEM) to investigate the thermal degradation behavior, structural modifications, and the surface texture of the cross-linked chitosan adsorbents, respectively. The adsorption results were analyzed by well-known kinetic and isotherm models. The kinetics of metal adsorption followed the pseudo-second-order model. The maximum sorption capacities obtained from the Langmuir isotherm model were 126?mg/g for diammonium phosphate-modified Chitosan (DMC) and 137?mg/g for DAP/EDTA-modified chitosan (EDMC). The thermodynamic analysis showed that the metal removal process was endothermic in nature.     

Adsorption of Pb(II) ions from aqueous solutions by carbon nanotubes oxidized different methods

This study investigated the heavy metal adsorption of the carbon nanotubes (CNTs) oxidized different methods. Besides the conventional ultrasonication method, the UV-light used as an oxidation agent. The two oxidation methods compared with each other by Pb(II) adsorption. The characterizations of oxidized CNTs were analyzed by FTIR, XRD, DTG, SEM and total acidity capacity analysis. The adsorption capacities of carbon nanotubes were compared with using Langmuir and Freundlich isotherms. Two different kinetic theories were applied to experimental data. These theories are pseudo-second order and intra-particle diffusion models. The adsorption results can be compared using non-linear Langmuir isotherm parameters. For single wall carbon nanotubes (SWCNTs), theoretical adsorption capacity value (Q_m) of UV-light method is 511.99 mg/g and ultrasonication method is 342.36 mg/g. The UV-light increased the surface acidity of the carbon nanotubes more than ultrasonication. After the adsorption experiments, it is apparently seen that the UV-light oxidation method is a useful method for heavy metal adsorption.     

Dehydrated Carbon Fiber for the Recovery of Pd(II) and Pt(II) From Chloride Aqueous Solution

Cellulose fiber was separated from date palm leaflets and was carbonized by dehydration using dilute sulfuric acid at 150°C. Produced dehydrated carbon fiber (DCF) was tested for the sorption of Pd(II) and Pt(II) at different pH, contact time, metal concentration, and temperature. With the rise in pH, sorption was found to increase for Pd(II) but decreases for Pt(II). The optimum pH ranges of 1-3 for Pt(II) and 3-3.5 for Pd(II). Approximate equilibrium was obtained within 50 hr for both metals with sorption data fitting the pseudo second order model well. Activation energy, Ea, was found to be higher than 40 kJ/mol for the sorption of both metals, indicating the involvement of chemical processes in metal sorption. The Langmuir isotherm was found to fit the sorption data more than other isotherms. Thermodynamic parameters were calculated and showed an involvement of chemical processes in metal sorption with stronger interaction for the carbon with Pb(II) than with Pt(II). Both of Pd(II) and Pt(II) were reduced to their respective elemental forms on the surface of the fiber as confirmed by scanning electron microscopy and x-ray diffraction.     

磁性羟基磷灰石改性氮化硼的铅吸附特性

利用共沉淀法制备了氮化硼（BN）掺杂磁性羟基磷灰石（MP）的复合材料（MPBN），通过SEM、BET、FTIR、XRD、XPS和VSM对MPBN形貌、孔径、比表面积、元素组成、晶型、表面官能团和磁性进行表征，利用单因素吸附实验研究MPBN对Pb(II)的吸附特性。结果表明，MP成功负载在BN的层状结构中，MPBN具有超顺磁性。当Pb(II)浓度为250 mg/L，温度为25 ℃，pH=6.0，MPBN投加量为0.4 g/L时，吸附量达到460.75 mg/g，其吸附过程符合准二级动力学模型和Langmuir等温模型，表明MPBN对Pb(II)的吸附过程主要归因于单分子层的化学吸附。通过热力学模型拟合得到吸附过程的H为94.76 kJ/mol，?S为339.61 J/molK，说明该吸附过程在常温下是自发的吸热过程。同时MPBN在5次循环使用后仍然表现出优异的稳定性和良好的可回收性。     

Removal of Pb(II) from Aqueous Solution by Cross-linked Starch Phosphate Carbamate

The adsorption process of Pb(II) ions from aqueous solution by water-insoluble starch phosphate carbamates was investigated. The influences of adsorption conditions, such as adsorption time, adsorbent dose, pH, content of the substituent groups, initial Pb(II) concentration, and temperature, were thoroughly studied. It was shown that an adsorption time of 20 min is sufficient to reach the adsorption equilibrium, the adsorption equilibrium data follow well the Langmuir isotherm model, and the adsorption of Pb(II) ions on cross-linked starch phosphate carbamate is endothermic in nature. For the cross-linked starch phosphate carbamate (CSPC3) with a phosphate group content of 3.10 mmol/g and a carbamate group content of 1.40 mmol/g, the maximum adsorption capacity evaluated from the Langmuir isotherm towards Pb(II) is 2.01 mmol/g. In addition, repeated adsorption/desorption cycles were performed to examine the reusability of adsorbents and the recovery efficiency of Pb(II) ions. The adsorption capacity of Pb(II) ions by CSPC3 decreased from 1.85 to 1.47 mmol/g for three cycles.     

Preparation of Low-Cost Adsorbents from Paper Industry Wastes and their Pb(II) Removal Behavior in Water

In this study, we prepare low-cost adsorbents from paper industry waste (newspaper (NP) and white paper (WP) waste) through a simple drying process and used them for Pb(II) removal. Characteristics, maximum Pb(II) removal capacities of prepared adsorbents, and Pb(II) removal mechanisms are investigated. The maximum amounts of adsorbed Pb(II) on NP and WP derived from the Langmuir isotherm are 42.4 and 18.5 mg·g^?1, respectively. This value is similar or more effective than commercial and other low-cost Pb(II) sorbents. It indicates that low-cost adsorbents prepared from paper industry waste have high potential as inexpensive and effective heavy metal adsorbents.     

Studies on the biosorption of Pb(II) ions using Pseudomonas putida

ABSTRACT

The complete removal of Pb(II) was achieved by intact Pseudomonas putida cells. The biosorption isotherm exhibited Langmuirian behaviour and followed pseudo-second-order rate kinetics. The standard Gibbs free energy change (?G°) for the biosorption of Pb(II) ions was found to be ?26.4 kJ mol^?1, attesting to a chemisorption process. Thermolysis of P. putida cells improved the Pb(II) binding capacity by around 27%. All the four components tested, namely DNA, protein, polysaccharide and lipid, were found to contribute to the uptake of Pb(II) ions. The possible mechanisms of Pb(II) binding by P. putida have been delineated.     

Investigation of Pb(II) adsorption onto natural and synthetic polymers

Adsorption of toxic metal ion Pb(II) onto two different insoluble humic acids (IHAs) obtained from Beysehir (BIHA) and Ermenek (EIHA) low grade lignites and two synthesized terpolymers: styrene-divinylbenzene-methacrylic acid (SDBM) and styrene-divinylbenzene allylmethacrylate (SDBAM) were investigated and compared with commercial activated carbon (AC). The synthesized polymers were characterized by FTIR. Effects of pH (in neutral and acidic range), time, and initial metal concentration on the effectiveness of IHAs and terpolymers were determined. All synthesized adsorbents could adsorb Pb(II) with much higher capacity at half of the retention of AC in acidic medium. The adsorption capacities varied in the range of 51–76 mg g⁻¹. The affinity order of polymers in acidic medium for Pb(II) ions was observed as: SDBAM>SDBM>BIHA≈EIHA>AC. IHAs fit Freundlich model while SDB polymers were fitting Langmuir isotherm. The maximum adsorption capacities in neutral medium were 48 mg g⁻¹ for SDBM and 15 mg g⁻¹ for BIHA. Desorption studies for the polymer of highest performance indicated that about 90% desorption was achieved at 5 h by using EDTA regenerant solution. The polymer can be used repeatedly in Pb(II) adsorption with close capacities to initial use. The higher selectivity of SDBAM to Pb(II) ions in multimetal solution was also indicated in the study. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

High surface area-activated carbon from Glycyrrhiza glabra residue by ZnCl2 activation for removal of Pb(II) and Ni(II) from water samples

A high-surface-area activated carbon was prepared by chemical activation of Glycyrrhiza glabra residue with ZnCl₂ as active agent. Then, the adsorption behavior of Pb(II) and Ni(II) ion onto produced activated carbon has been studied. The experimental data were fitted to various isotherm models. According to Langmuir model, the maximum adsorption capacity of Pb(II) and Ni(II) ions were found to be 200 and 166.7 mg g⁻¹, respectively, at room temperature. Kinetic studies showed the adsorption process followed pseudo second-order rate model. High values of intra-particle rate constants calculated shows the high tendency of activated carbon for removal of Pb(II) and Ni(II) ions.     

Recent studies in adsorption of Pb(II), Zn(II) and Co(II) using conventional and modified materials:a review

ABSTRACT

Heavy metal contamination and its detrimental effects on human health and environment have been a worldwide concern. Over the years, various technologies have been adapted to tackle this problem. Adsorption is still considered to be one of the most feasible and cost-effective methods for treating wastewater contaminated with heavy metals. Adsorbents such as activated carbon, clay, zeolites and silica have been studied extensively in the past. Modification of these conventional adsorbents and the synthesis of nonconventional adsorbents such as nanocomposites and metal organic frameworks (MOF’s) have been the main focus of study in recent times. This review article attempts to present a detailed account of various adsorbents and their removal efficiencies for the treatment of wastewater contaminated with lead(II), zinc(II) and cobalt(II) in the current decade. Influence of various parameters, adsorption isotherms and kinetics best described for their removal have also been reviewed in detail. It is observed that most of the adsorbents followed pseudo second order kinetics suggestive of a chemisorption process. After conducting a thorough review of more than 120 recently published papers, it can be inferred that nanomaterials and nanocomposites have shown excellent adsorption capacity for removal of these heavy metals.