Poly(itaconic acid)-assisted ultrafiltration of heavy metal ions’ removal from wastewater

The complexation–ultrafiltration technique has been introduced as a capable system to remove heavy metals ions from wastewater. This method needs a water-soluble polymer; therefore, in this paper we synthesized super water-soluble poly(itaconic acid) (PITA) and employed it in polymer-assisted ultrafiltration process to remove Pb(II) ions from synthetic wastewater solutions. The itaconic acid can be produced from different agricultural products and is a green and eco-friendly material. Factors influencing the removal of the metals ions including poly(itaconic acid) concentration, pH and permeate flux were investigated. The results showed that the maximum percentage of metal ion removal was obtained in the basic pH (pH > 7). The flux test was performed by 200 mg/L of poly(itaconic acid) and after 60 min, the flux of membrane was 33.4 L/m²h. The simultaneously selective removal ability of the poly(itaconic acid) for adsorption of different metal ions (Pb²⁺, Sn²⁺, Cu²⁺, Zn²⁺, and Cd²⁺) was also studied. The trend of rejection was Pb²⁺ > Cu²⁺ > Sn²⁺ > Zn²⁺ > Cd²⁺. The highest rejection of Pb(II) ions was achieved as 86%. Generally, the results of this research demonstrated that poly(itaconic acid) (with two carboxyl groups on its repeating unit) is more effective in removing heavy metals ions from wastewater in comparison with customary polymers.

     

Metal recovery from jarosite waste – A resin screening study

Work has been carried out screening hydrometallurgical resins for application in the valorization of industrially produced jarosite. Of the seven resins tested, anion exchange resins performed poorly for valuable metal recovery. Purolite S950+ and S957, along with a strong acid resin, show good extraction properties, but are selective for Fe³⁺ over the other (divalent) metals. Purolite S930+ (iminodiacetic acid-functionalized resin) demonstrates selectivity for Cu²⁺ over Fe³⁺, but poor selectivity for Ni²⁺, Zn²⁺, and Co²⁺. Dowex M4195 (bispicolylamine-functionalized resin) demonstrates promise for extracting metals of value away from a mixed metal pregnant liquor solution (PLS). A three-stage column-based recovery process is proposed for jarosite leachate treatment.     

Removal of heavy‐metal ions from aqueous solution with nanochelating resins based on poly(styrene‐alt‐maleic anhydride)

Chelating resins have been considered to be suitable materials for the recovery of heavy metals in water treatments. A chelating resin based on modified poly(styrene‐alt‐maleic anhydride) with 2‐aminopyridine was synthesized. This modified resin was further reacted with 1,2‐diaminoethan or 1,3‐diaminopropane in the presence of ultrasonic irradiation for the preparation of a tridimensional chelating resin on the nanoscale for the recovery of heavy metals from aqueous solutions. The adsorption behavior of Fe²⁺, Cu²⁺, Zn²⁺, and Pb²⁺ ions were investigated by the synthesis of chelating resins at various pH's. The prepared resins showed a good tendency for removing the selected metal ions from aqueous solution, even at acidic pH. Also, the prepared resins were examined for the removal of metal ions from industrial wastewater and were shown to be very efficient at adsorption in the cases of Cu²⁺, Fe²⁺, and Pb²⁺. However; the adsorption of Zn²⁺ was lower than those of the others. The resin was characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, X‐ray diffraction analysis, and differential scanning calorimetry analysis. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Preparation of polysulfonebenzylthiourea-reactive ultrafiltration plate membranes and their rejection properties for heavy toxic metal cations

The asymmetric membranes were prepared via phase inversion method, by using chloromethyl polysulfone as membrane materials, polyethylene glycol (PEG) as pore forming agent to improve the morphology and function of resultant membranes, N,N-dimethylacetamide as solvent, and water as the extraction solvent. Then the highly qualified polysulfonebenzylthiourea-reactive ultrafiltration plate membrane was prepared successively through the reactions between the chloromethyl polysulfone matrix membrane and thiourea. The thiourea-functionalized polysulfone plate reactive ultrafiltration membrane was used for the rejection of heavy toxic metal cations such as Cd²⁺ and Zn²⁺ through the coordination of the thiourea group and heavy toxic metal cations, in which the effects of the morphological and the structure of the membrane on the rejection properties were investigated. The rejection conditions, including the concentration of heavy toxic metal cations, temperature and pH of the solution had significant effects on the rejection capacity of polysulfonebenzylthiourea-reactive ultrafiltration membrane. The reactive ultrafiltration membrane containing thiourea group can be conveniently recovered by dilute hydrochloric acid for coordination of heavy toxic metal cations, which would have wide application for the treatment of waste-water-containing heavy toxic metal cations. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci 2008     

Preparation and Characterization of Cellulose Acetate/Aminated Polysulfone Blend Ultrafiltration Membranes and their Application Studies

Abstract

Ultrafiltration membranes are largely being applied for heavy metal ion separations from aqueous streams. Cellulose acetate (CA) and aminated polysulfone (APSf) based membranes are prepared in the absence and presence of the polymeric additive, polyethylene glycol, PEG 600, in various compositions. The effects of polymer blend composition and additive concentration on compaction, pure water flux, membrane hydraulic resistance, water uptake, and contact angle has been investigated to evaluate the performance of the membranes and the results are discussed. Surface and cross-sectional morphologies of membranes were also analyzed using scanning electron microscopy. Toxic heavy metal ions such as Cu²⁺, Ni²⁺, Cd²⁺, and Zn²⁺ were separated by the blend membranes using polyethyleneimine (PEI) as polymeric ligand. The rejection and permeate flux efficiencies of the blend membranes are compared with pure cellulose acetate membranes.     

Charged membrane ultrafiltration of heavy metal salts: Application to metal recovery and water reuse

An experimental investigation is presented of the thin-channel ultrafiltration of 0.6 × 10^?3 M to 15.0 × 10^?3 M aqueous solutions of Cu²⁺, Ni²⁺, or Zn²⁺ sulfate or chloride salts through a negatively-charged, non-cellulosic membrane. Multi-salt solutions and the actual rinse water from a Watts-type-nickel-plating process are also ultrafiltered. The membrane provides a Ni²⁺ rejection of 0.83 and water flux of 1.0 × 10³ cm/sec (23 gal/ft² day) at a transmembrane pressure difference of 4.0 × 10⁵ N/m² (3.9 atm). The membrane rejection and water flux data are utilized in a computer simulation procedure for scale-up to a multi-module, two-staged process for the closed-loop operation of a plating plant.     

Sorption characteristics of heavy metal ions by a natural zeolite

Zeolites have been shown to be effective adsorbents for the removal of heavy metals from aqueous solutions. A natural material from Cuba, containing zeolite, has been used for the removal of several metal ions, namely Cu²⁺, Zn²⁺, and Ni²⁺, to evaluate its potential use as a low‐cost adsorbent. Batch experiments have been conducted to evaluate the process kinetics and the removal equilibrium at different pH values, metal and zeolite concentrations. Pseudo‐second order kinetics and Freundlich equilibrium parameters have been obtained. Results suggested that this natural zeolite has a high potential for heavy metal retention. The selectivity of the studied metals was determined as Cu²⁺ ? Zn²⁺ > Ni²⁺, related to the first hydrolysis equilibrium constant. The metal removal efficacy was strongly dependent on pH, and to a lesser extent on metal/zeolite ratio. Copyright © 2005 Society of Chemical Industry     

Removal of Heavy Metal Ions from Water by Cross-Linked Potato Di-Starch Phosphate Polymer

Potato di-starch phosphate polymer was synthesized by cross-linking potato starch with phosphorus oxy-chloride in basic medium and was then dispersed (0.2-1%) in aqueous solutions of divalent heavy metal ions (Cu²⁺, Ni²⁺, Zn²⁺, and Pb²⁺), to investigate their removal efficiency by the starch and was found to increase with increase in the polymeric starch content and increase in the heavy metal ion concentration. The removal order was found to be Pb²⁺ (78.1%) > Cu²⁺ (58.5%) > Zn²⁺ (20.5%) > Ni²⁺ (17.3%) against the constant polymeric starch content. UV-Visible, Fluorescence, FT-IR, SEM, and CHN techniques were used for characterization of different complexes formed.     

Polymer-based metal adsorbents via graft copolymerization of polyvinyl alcohol with diaminomaleonitrile: A green chemistry approach

Synthesis, characterization, and amidoximation of diaminomaleonitrile-functionalized polyvinyl alcohol (PVA) grafts were studied. Ceric ammonium nitrate (CAN) was used as an initiator in an aqueous nitric acid medium under N₂ atmosphere. Optimum conditions for grafting were as follows: monomer concentration [DAMN] = 1.4M, [CAN] = 16 × 10⁻² mol/L, T = 50°C, and t = 2 h. Water uptake of the PVA graft films increased with the increase of grafting yield. The imparted cyano group of the grafted PVA polymer chains (with degree of grafting up to 136%) was converted into amidoxime group by the reaction with hydroxylamine hydrochloride. The grafted polymers were characterized by FTIR spectroscopy, differential scanning calorimetry, and thermal gravimetric analysis. The grafted PVA films are more thermally stable than the ungrafted PVA membrane, because the grafted membrane showed a single degradation pattern despite having two components. A decrease in T_g values is observed as the grafting yield of copolymers increases indicating the incorporation of polydiaminomaleonitrile chains in amorphous copolymers with higher thermal stability. The prepared amidoximated DAMN136-g-PVA was investigated for its properties in removing heavy toxic metals, such as Pb²⁺, Cd²⁺, Zn²⁺, Fe³⁺, Cu²⁺, Ni²⁺, and Co²⁺ from water. The amidoximated film is characterized by a considerably greater binding ability with respect to heavy metals. The nature of the metal ion also has great importance in the amount binding to the polymeric material. The kinetics of the sorption/desorption process for Co²⁺, Ni²⁺, and Zn²⁺ were investigated. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Use of Masking Agents in Promoting Selective Transport of Zn2+ through Nafion Membrane

ABSTRACT

The effect of H⁺ ion concentration on the ion-exchange selectivity of Nafion 117 cation-exchange membrane toward Zn²⁺, Pb²⁺, Cu²⁺, Al³⁺, and Fe³⁺ have been studied. A selective transport of any particular metal ion was not possible by controlling the pH alone. However, selective permeation of Zn²⁺ across the membrane could be accomplished by selectively masking the metal ion as the cationic 1,10-phenanthroline complex while the permeation of other interfering ions could be suppressed by masking them as their anionic EDTA complex. About 20% of Zn²⁺ selectively permeated from the mixture in 6 hours and the quantity increased to 67% after 60 hours of permeation.     

Synthesis,characterization, and amidoximation of diaminomaleodinitrile-functionalized polyethylene terephthalate grafts for collecting heavy metals from wastewater

Synthesis, characterization, and amidoximation of diaminomaleodinitrile-functionalized polyethylene terephthalate (PET) grafts were studied. Azobisisobutyronitrile (AIBN) was used as an initiator. Optimum conditions for grafting were as follows: monomer concentration [DAMN] = 0.5M, [AIBN] = 1.50 × 10⁻³ mol/L, T = 80°C and t = 3 h. Water uptake of the grafted-PET film increased with the increase of grafting yield. The imparted cyano group of the grafted polymer chains (with degree of grafting up to 83%) was converted into amidoxime group by reaction with hydroxylamine. The unique advantage of this polymer is that it contains double amidoxime groups per repeating unit and an additional diethylene spacer unit between neighboring amidoxime groups in each monomeric unit. The grafted-PET films were characterized by FTIR spectroscopy, differential scanning calorimetry (DSC), and thermal gravimetric analysis (TGA). The grafted-PET films are more thermally stable than the ungrafted-PET membrane, since the grafted membrane showed a single degradation pattern despite having two components. A decrease in T_g values is observed as the grafting yield of copolymers increases indicating the incorporation of polydiaminomaleodinitrile chains in amorphous copolymers with higher thermal stability. The prepared amidoximated DAMN83-g-PET was investigated for its properties in removing heavy toxic metals, such as Pb²⁺, Cd²⁺, Zn²⁺, Fe²⁺, Cu²⁺, Ni²⁺, Co²⁺, and Ag¹⁺ from waste water. The amidoximated-film is characterized by a considerably greater binding ability with respect to heavy metals. The nature of the metal ion also has great importance in the amount binding to the polymeric material. The kinetics of the sorption/desorption process for Co²⁺, Ni²⁺, and Zn²⁺ are investigated. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Characterization and adsorption behavior of newly synthesized sodium bis(2-ethylhexyl) sulfosuccinate–cerium (IV) phosphate (AOT–CeP) cation exchanger

A new cationic exchange material, sodium bis(2-ethylhexyl) sulfosuccinate (AOT) with cerium (IV) phosphate (AOT–CeP) has been synthesized. The characterization of the ion exchanger was performed by using infra red spectroscopy (IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), thermo gravimetric analysis/differential thermo gravimetric analysis (TGA/DTA/DTG) and elemental analysis. The ion exchange properties like ion exchange capacity, elution and concentration behavior of AOT–CeP were determined by taking the material into a column and elution of H⁺ was done by NaNO₃. The thermal stability of the ion exchanger was studied by determining ion exchange capacity after heating to different temperatures for one hour. The adsorption studies on AOT–CeP demonstrated that the material is selective for Cu²⁺, Pb²⁺, Cd²⁺, Zn²⁺ and Hg²⁺ ions. AOT–CeP was found to be effective for the separation of Cu²⁺, Pb²⁺, Cd²⁺, Zn²⁺ and Hg²⁺ ions in the presence of alkali metals/alkaline earth metals. This cationic exchanger was also effective for the removal of Cu²⁺, Pb²⁺, Cd²⁺, Zn²⁺ and Hg²⁺ ions in the presence of acid and other transition metal ions. Thus, AOT–CeP can be used for the removal of these ions from the waste water during its treatment.     

Effect of light metal ions on the sorption of heavy metal ions on natural polymers

Dried ground formaldehyde-treated peanut skins, white ash bark, and So. Wisconsin red maple bark are efficient substrates for removal of many heavy metal ions from waste streams, but possible interference by common light metal cations has never been determined. The influence of Ca²⁺, Mg²⁺, or Na⁺ on the removal of the heavy metal ions Pb²⁺, Cu²⁺, Cd²⁺, and Zn²⁺ by the above substrates was studied in both batch and packed-column experiments. It was found that Pb²⁺ and Cu²⁺ were minimally affected by the presence of these light metal ions in solution, while the uptake of Cd²⁺ and Zn²⁺ was significantly reduced. Calcium ion produced the greatest effect of the light metals tested.     

Polyurethane and sulfonated polysulfone blend ultrafiltration membranes: II. Application studies

Ultrafiltration membranes are largely being applied for macromolecular and heavy metal ion separations from aqueous streams. Polyurethane‐ and sulfonated‐ polysulfone‐based membranes prepared in the absence and presence of the polymeric additive, poly(ethylene glycol) 600, in various compositions, were subjected to the rejection of macromolecular proteins, such as bovine serum albumin, egg albumin, pepsin and trypsin. Toxic heavy metal ions such as Cu²⁺, Ni²⁺, Cd²⁺ and Zn²⁺ were subjected to rejection by the blend membranes by complexing them with a polymeric ligand, polyethyleneimine. The effects of polymer blend compositions and additive concentrations on the rejection and permeate flux of both proteins and metal ions are discussed. The rejection and permeate flux efficiencies of the blend membranes are compared with pure sulfonated polysulfone membranes. © 2003 Society of Chemical Industry     

Selective removal of copper ions from multi‐component aqueous solutions using modified silica impregnated with LIX 84

A silica support impregnated with 2‐hydroxy‐5‐nonylacetophenone oxime (LIX 84) was prepared after surface modification by ‐aminopropyltriethoxysilane. Fixed‐bed tests were conducted to investigate the capabilities of the prepared adsorbent with respect to the selective removal of copper ions from multi‐metal solutions. Break‐through curves were obtained using the modified silica for a solution containing Cu²⁺, Cd²⁺, Ni²⁺, Co²⁺ and Zn²⁺, as well as an industrial electronics wastewater sample. The copper adsorption capacities for the multi‐metal solution and the wastewater were 0.175 and 0.198 mmolg⁻¹, respectively under the conditions used in this study. The copper recovery ratios for the modified silica treated with the multi‐metal solution and the wastewater were 86 and 91%, respectively after treating with 0.1 moldm⁻³ HNO₃. The results show that the modified silica, prepared here, has potential value for the selective removal of copper ions from multi‐component aqueous solutions containing multi‐metals using a fixed‐bed reactor. © 2000 Society of Chemical Industry     

Charged Membrane Ultrafiltration of Toxic Metal Oxyanions and Cations from Single- and Multisalt Aqueous Solutions

Abstract

With application to the treatment of nonferrous metals production streams, the toxic metals As(V), Se(IV), As(III), and Cd(II) are separated from single-and multisalt aqueous solutions by continuous-flow, membrane ultrafiltration with charged, noncellulosic membranes. The single-salt aqueous solutions of As(V), Se(IV), As(III), or Cd(II) are investigated over pH 5 to 10, metal concentrations in the range 0.5 to 20.0 mM, and transmembrane pressure differences from 2.8 × 10⁵ to 5.6 × 10⁵ N/m², with the effects of these three independent variables established on the metal rejections. The rejections of the monovalent oxyanions H₂AsO₄ ^?, HSeO₃ ^?, and H₂AsO₃ ^? (with sodium as the counterion) are of the order 0.85, and those of the divalent HAsO₄ ^2?, SeO₃ ^2? (and SO₄ ^2?), and of Cd²⁺ are of the order 0.95 for 6.0 mM feed streams. Comparisons are made with the halides, NO₃ ^?, and ClO₄ ^?. The rejection behavior of multisalt solutions of H₂AsO₄ ^? and HSeO₃ ^? is not influenced by the presence of sulfate, but Cd²⁺ produces a decrease in the rejection of Se(IV). For feed streams 2.0 mM each in H₂AsO₄ ^?, HSeO₃ ^?, Cd²⁺, and Zn²⁺ at pH 5, the presence of a high sulfate concentration does not affect the metal rejections, except at greater than 14.0 mM where the Se(IV) rejection begins to decline sharply     

A study on acid reclamation and copper recovery using low pressure nanofiltration membrane

In this study, nanofiltration membrane is used to separate proton (H⁺) and copper ions from a ternary ions mixture (H⁺, Cu²⁺, SO₄^2?). The performance of membrane in separating Cu²⁺ and H⁺ was tested under the effect of pressure, concentration and different acid strength (pH). It was found that the H⁺ rejection is independent of the applied pressure. Permeability of solution decreased linearly with the increase of CuSO₄ concentration. In terms of H⁺ rejection, there is a continuous drop in rejection from 0.1 mM CuSO₄ to 10 mM CuSO₄ solution. H⁺ was poorly retained and concentrated in the permeate stream in corresponding to the electro-neutrality requirements, on the other hand, the rejection of copper ion was almost constant with pH. In overall, optimum acid reclamation and copper recovery can be achieved at higher volume flux. A Three Parameters-Combined Film-Extended Nernst-Planck Equation (CF-ENP) model is successfully applied to predict the performance of nanofiltration membrane in separating the ternary ions.     

Removal of lead,copper, nickel,cobalt, and zinc from water by a cancrinite-type zeolite synthesized from fly ash

As a low Si/Al ratio zeolite, cancrinite received very scant study in previous studies on the adsorption removal of heavy metals from water. In this study, a cancrinite-type zeolite (ZFA) was synthesized from Class C fly ash via the molten-salt method. Adsorption equilibriums of Pb²⁺, Cu²⁺, Ni²⁺, Co²⁺, and Zn²⁺ on ZFA were studied in aqueous solutions and were well represented by Langmuir isotherms. The increase of pH levels during the adsorption process suggests that the uptake of heavy metals on ZFA was subjected to an ion exchange mechanism. It is found that the maximum exchange level (MEL) follows the order: Pb²⁺ (2.530 mmol g^?1) > Cu²⁺ (2.081 mmol g^?1) > Zn²⁺ (1.532 mmol g^?1) > Co²⁺ (1.242 mmol g^?1) > Zn²⁺ (1.154 mmol g^?1). Comparison with previous studies shows that the MEL of ZFA is higher than the commonly used natural zeolites; and it is also comparable to (or higher than) several synthetic zeolites and ion exchange resins. The high MEL of heavy metals on ZFA is attributed to the high cation exchange capacity (CEC) and proper pore size of cancrinite. The pseudo-first-order kinetics suggests that the ion exchange processes were diffusion-controlled.     

Selective Transport of Copper(I,II), Cadmium(II), and Zinc(II) Ions through a Supported Liquid Membrane Containing Bathocuproine,Neocuproine, or Bathophenanthroline

Abstract

Some selective transport systems for heavy metallic ions through a supported liquid membrane (SLM) containing a 2,2′-dipyridyl derivative ligand, 4,7-diphenyl-2,9-dimethyl-1,10-phenanthroline (bathocuproine), 2,9-dimethyl-1,10-phenanthro-line (neocuproine), or 4,7-diphenyl-1,10-phenanthroline (bathophenanthroline), were investigated. The transport of copper(I, II), cadmium(II), zinc(II), lead(II), and cobalt(II) ions was accomplished with a halogen ion such as chloride, bromide, or iodide ion as a pairing ion species for any SLM. The ranking of the permeability of the metallic ions was Cu^+,2+, Zn²⁺, Cd²⁺ ? Pb²⁺, Co²⁺. When the oxidation-reduction potential gradient was used as a driving force for metallic ions, the transport of Cu⁺ ion was higher than those of Cd²⁺ and Zn²⁺ ions for any SLM containing bathocuproine, neocuproine, or bathophenanthroline. On the other hand, in the transport system which used the concentration gradient of pairing ion species, the permeability of the Cu²⁺ ion decreased whereas that of the Cd²⁺ ion increased. Moreover, it was found that the different selectivity for the transport of metallic ions is produced by using various pairing ion species.     

Chelation ion‐exchange properties of copolymer resin derived from 4‐hydroxyacetophenone,oxamide, and formaldehyde

A copolymer (4‐HAOF) prepared by condensation of 4‐hydroxyacetophenone and oxamide with formaldehyde in the presence of an acid catalyst proved to be a selective chelating ion‐exchange copolymer for certain metals. Chelating ion‐exchange properties of this copolymer were studied for Fe³⁺, Cu²⁺, Ni²⁺, Co²⁺, Zn²⁺, Cd²⁺, Pb²⁺, and Hg²⁺ ions. A batch equilibrium method was employed in the study of the selectivity of metal‐ion uptake involving the measurements of the distribution of a given metal ion between the copolymer sample and a solution containing the metal ion. The study was carried out over a wide pH range and in media of various ionic strengths. The copolymer showed a higher selectivity for Fe³⁺ ions than for Co²⁺, Zn²⁺, Cd²⁺, Pb²⁺, Cu²⁺, Ni²⁺, and Hg²⁺ ions. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 787–790, 2003