Removal Efficiency Of Cu Research Articles

Characteristics of heavy metals capturing agent dithiocarbamate (DTC) for treatment of ethylene diamine tetraacetic acid–Cu (EDTA–Cu) contaminated wastewater

An efficient and water-soluble (102g/kg at 293K) heavy metals capturing agent was developed for removal of copper in ethylene diamine tetraacetic acid–Cu (EDTA–Cu) wastewater. The agent was synthesized through nucleophilic reaction of carbon disulfide and hydrazine hydrate. Infra-red, ultraviolet and 13C Nuclear Magnetic Resonance (NMR) spectra and elemental analysis demonstrated that the agent was one of Tetrathio Bicarbamic Acid (C2H4N2S4) containing dithiocarbamate groups and was named DTC–TBA for short. Effect of DTC–TBA dosage, pH, reaction time, flocculant polyacrylamide (PAM) dosage and temperature on Cu2+ removal efficiency was investigated through single factor batch jar experiment for treatment of simulated EDTA–Cu wastewater with DTC–TBA. The optimized condition was pH of 3–5, molar ratio of DTC–TBA/Cu of 1.2:1, reaction time of 3min, and PAM dosage of 2–6mg/L. The removal efficiency of Cu2+ was greater than 99% with initial concentration of 100–1000mg/L, and the maximum adsorption capability with DTC–TBA towards Cu2+ was 287.05mg/g. Treatment of actual EDTA–Cu wastewater showed that DTC–TBA was efficient and average concentration of residential Cu2+ was 0.372mg/L. These results indicated that DTC–TBA was stable in acidic condition and promising for application even when pH was below 3. Cu2+ was replaced by DTC–TBA at a stoichiometric ratio from EDTA–Cu. The adsorption kinetics and isotherm data could be well elucidated with pseudo-second-order equation and Langmuir model respectively. Thermodynamic parameters, involving ΔHO, ΔSO and ΔGO were also calculated to prove the adsorption process being exothermic and spontaneous.

Comparative study of simultaneous removal of As, Cu, and Pb using different combinations of electrokinetics with bioleaching by Acidithiobacillus ferrooxidans

Different designs of electrokinetics were applied to simultaneously remove arsenic, copper, and lead from contaminated soils. Single electrokinetics (control) resulted in superior removal efficiencies for Cu (73.5%) and Pb (88.5%), though the removal of As (3.11%) was relatively little. Sequential bioelectrokinetics of bioleaching with Acidithiobacillus ferrooxidans and electrokinetics enhanced the removal of As (25%), while Pb exhibited a significant decrease in removal efficiency (10.6%), due to the formation of insoluble compounds. In order to improve the overall performance, integrated bioelectrokinetics was designed by inoculating A. ferrooxidans into the electrolyte after 5 or 15 days of electrokinetics. Lead (75.8%) and copper (72%) were effectively removed through electrokinetics, after which arsenic (35%) was more efficiently removed by bioleaching-enhanced electrokinetics. A pilot-scale experiment indicated that integrated bioelectrokinetics is an effective means of remediation of soils contaminated with multiple heavy metals and arsenic.

Preparation and Application of Electrospinning Membranes of Thermoplastic Carboxymethyl Cellulose/PLA for Removal of Cu<sup>2+</sup> from Aqueous Solutions

A composite membrane of thermoplastic carboxymethyl cellulose (TCMC) /PLA was prepared by electrospinning process, and crossliked by epichlorohydrin solution at different temperature. The cross-linking temperature was optimized by characterizing the morphology and tensile strength of the film. The optimal cross-linking temperature was 50°C. A composite membrane was used to remove Cu2+ from aqueous solutions, and the effects of initial concentration of Cu2+ and contact time on the removal efficiency of Cu2+ were investigated. The removal efficiency of Cu2+ was 13.78%, at the initial concentration of 40 mg·L-1 and contact time of 30s.

Experimental Research for Heavy Metal Lead and Zinc Smelting Wastewater by Electroflocculation

In this paper,author use electroflocculationt to deal with heavy metal lead and zinc smelting wastewater,disiscussing the impact of electroflocculation to heavy metal removal rate under different pH,electrolytic voltage,electrolysis time ,plate spacing conditions. The results show that: heavy metal removal rate achieve the best effects when the situationgs is that pH is 11, electrolysis voltage is 2v, electrolysis time is 30 min , plate spacing is 1.2cm.Cd removal efficiency is 100% ,99.92 % removal efficiency of Zn,95.53% removal efficiency of Pb and 98.64% removal efficiency of Cu

Heavy Metals Removal from Swine Wastewater Using Constructed Wetlands with Horizontal Sub-Surface Flow

The removal efficiency of Cu and Zn from swine wastewater was evaluated as effected by three variables: the hydraulic retention time (HRT) (24, 48, 72 and 96 hours), two different plant species (Typha domingensis Pers. and Eleocharis cellulosa) and two different sizes of filter media (5 and 15 mm) using a horizontal sub-surface flow constructed wetland. From the results, a significant difference was observed in the removal efficiency of Cu and Zn with respect to different hydraulic retention times. The best results were obtained in the HRT of 96 hours for Zn where 96% removal of Zn with Typha domingensis Pers. specie with gravel of 15 mm (experimental unit 6) was achieved. For Cu, at 72 hours of HRT, the efficiency was nearly 100% in five of the six study units (1, 2, 3, 5 and 6). In contrast, in experimental unit 4 with gravel of 15 mm and without plants, only 86% Cu removal was achieved.

Fe nanoparticle-functionalized multi-walled carbon nanotubes: one-pot synthesis and their applications in magnetic removal of heavy metal ions

Magnetic-functionalized multi-walled carbon nanotubes (MWCNTs) with encapsulated Fe nanoparticles have been successfully fabricated via a one-step decomposition approach using ferrocene as a single precursor at a high temperature of 950 °C. The constituents, phase, and morphology have been characterized by X-ray diffraction, Raman spectroscopy and transmission electron microscopy (TEM). Magnetic measurements reveal the ferromagnetic nature of the material with a magnetization saturation of 82.6 emu g−1 at room temperature. Full nitrogen sorption isotherms show that the magnetic-functionalized MWCNTs have a porous structure (2.0 nm, 6.42 nm and 11.4 nm) and large surface area (295.4 m2 g−1). Owing to their wonderful intrinsic properties, these magnetic-functionalized MWCNTs exhibit excellent ability to remove heavy metal ions from aqueous solutions. For example, the removal efficiency can be up to 97% at a Cu2+ concentration of 100 mg L−1 using these magnetic-functionalized MWCNTs as adsorbents. In addition, because the Fe nanoparticles were wrapped by MWCNTs, the material can be used in acidic solution and the removal efficiency of Cu2+ can reach 90% even in a strong acid solution (pH = 1).

폐미역을 이용한 생물흡착 시스템별 중금속 제거 효율 평가

폐미역을 이용한 생물흡착제의 중금속 제거능력을 조사하기 위해 lab-scale의 생물흡착시스템에서 최적조건을 구명하고, lab-scale의 생물흡착시스템의 최적조건하에서 large-scale PBCC 시스템의 중금속 제거능력을 조사하였다. Lab-scale 생물흡착시스템별 중금속 제거능력은 PBCC보다 CSTR이 뛰어났지만 CSTR은 폐수유입속도가 48 L/day이상에서 완전혼합상태를 유지하지 못하여 안정적인 운전이 가능한 PBCC가 적합하였다. Cu용액의 유입속도 및 농도별 Cu 제거능력은 유입속도 12 L/day 및 유입농도 10 mg/L일 때 Cu용액 처리량이 가장 뛰어났으나 경제적인 부분을 검토한 결과 유입속도 24 L/day 및 유입농도 100 mg/L가 적절할 것으로 판단되었다. 처리단계별 Cu 제거능력은 컬럼을 연속식으로 배열하는 것이 Cu 제거효율이 높았다. 중금속 종류별 제거능력은 Pb, Cr의 처리효율이 높았고 Cu용액 이외의 다른 중금속 용액들도 Cu와 동등한 수준 이상의 처리효율을 나타내었다. Lab-scale의 PBCC 시스템을 27배 규모로 scale-up한 large-scale PBCC 시스템의 Cu 제거능력은 138 L로 lab-scale의 5 L와 비교하였을 때 동등한 수준을 유지하였다. 따라서 중금속 처리를 위한 최적 폐미역 활용 생물흡착시스템은 PBCC 시스템인 것으로 판단되나, 실제 중금속 폐수에 본 최적시스템을 적용하기 위해서는 중금속 폐수 특성에 따른 적용성 연구가 추가로 진행되어야 할 것으로 판단된다. BACKGROUND: Heavy-metal pollution represents an important environmental problem due to the toxic effects of metals, and their accumulation throughout the food chain leads to serious ecological and health problems. METHODS AND RESULTS: Optimum conditions in continuous-flow stirred tank reactor (CSTR) and packedbed column contactor (PBCC) using brown seaweed biosorbent were investigated. Under optimum conditions from both lab-scale biosorbent systems, removal efficiency of copper (Cu) in a large-scale PBCC system was investigated. Removal capacity of Cu using brown seaweed biosorbent in a lab-scale CSTR system was higher than that in a lab-scale PBCC system. On the other hand, over 48 L/day of flow rate in Cu solution, removal efficiency of Cu in a lab-scale PBCC system was higher than that in a lab-scale CSTR system. Optimum flow rate of Cu was 24 L/day, optimum Cu solution concentration was 100 mg/L. Removal capacity of Cu at different stages was higher in the order of double column biosorption system > single column biosorption system. Under different heavy metals, removal capacities of heavy metal were higher in the order of Pb > Cr > Ni > Mn <TEX>${\geq}$</TEX> Cu <TEX>${\geq}$</TEX> Cd <TEX>${\fallingdotseq}$</TEX> Zn <TEX>${\geq}$</TEX> Co. Removal capacity of Cu was 138 L in a large-scale PBCC system. Removal capacity of Cu a large-scale PBCC system was similar with in a lab-scale PBCC system. CONCLUSION(s): Therefore, PBCC system using brown seaweed biosorbent was suitable for treating heavy metal wastewater.

Enhanced coagulation for treating slightly polluted algae-containing surface water combining polyaluminum chloride (PAC) with diatomite

The feasibility of using raw diatomite for advanced treatment of slightly polluted algae-containing surface water was investigated in this study. Results demonstrated that the addition of diatomite is advantageous due to reduction of the polyaluminum chloride (PAC) dose required for satisfactory treatment of algae and improvement of the removal efficiency of natural organic material and heavy metals in surface water. The use of diatomite as a coagulant aid improves interparticle bridging thus incorporating the cells into flocs more efficiently, producing settleable flocs of greater density, size and strength. The enhanced coagulation has a wide working pH range and is less sensitive to environmental temperature. It has also been found that adding diatomite at the same time or before PAC enhances algae removal. The removal efficiency for UV254 was improved by 8.3–24.4% by combining PAC and diatomite. At the diatomite dosing rate of 1500 mg/L, the removal efficiency of Cu 2+, Pb 2+ and Cd 2+ reached 57.5%, 83.7% and 22.2% respectively. It is concluded that the enhanced coagulation through the combination of PAC and diatomite, as coagulant aid and adsorbent, is more effective and efficient than traditional coagulation for economic treatment of slightly polluted algae-containing surface water.

Removal of chelated Cu(II) from aqueous solution by adsorption–coprecipitation with iron hydroxides prepared from microelectrolysis process

Iron hydroxides prepared from microelectrolysis process were applied to remove EDTA-chelated copper from aqueous solution through adsorption–coprecipitation. To eliminate the occurrence of adverse reactions, Fe(II)-rich effluent of microelectrolysis was pretreated by continuously flushing N 2 for 15 min to eliminate dissolved oxygen, then iron hydroxides were generated in less than 30 s. The experimental results showed that Fe(II) yields could achieve 530.00–748.00 mg/L after 60-min operation of microelectrolysis process at the initial pH of 2.0–2.3. The uptake rate of Cu(II) by iron(II) hydroxides was so rapid under nitrogen-aerated condition that 100% of Cu(II) was removed within only 5 min at an initial Fe(II) concentration of 374.0 mg/L. However, Cu(II) would desorb from iron hydroxides when iron(II) hydroxides were gradually oxidized into iron(III) hydroxides by oxygen, indicating that iron(II) hydroxide had much higher adsorptive capacity for chelated Cu(II) than iron(III) hydroxide. In addition, iron(II)/(III) hydroxides prepared from microelectrolysis process exhibited a higher removal efficiency of Cu(II) than iron hydroxides prepared from FeSO 4·7H 2O, especially under air-aerated condition. This research provided a novel method for efficient removal of both Cu(II) and EDTA from Cu(II)-chelated wastewater.

Purification of Some Heavy Metals from Paper-Making Wastewater by Reed of Shuangtai Estuary Wetland

Abstract Through sampling reed in Shuangtai estuary wetland in April, 2009 and simulation test in Shenyang Agricultural University, we analyze the removal efficiency of Cu, Zn, Pb and Cd during different growth period of reed and distribution of them in various parts of reed. The results show that the removal efficiency is best in jointing stage, the removal of Pb largest with 21% increase and 30% in sprout and exhibition leaf period, the removal of Zn largest with 53% and 29% increase in jointing stage and the maturity period, the removal of Cd largest with 40% increase in the different growing season. The absorption amount of Cu, Zn, Pb and Cd in roots of reed reaches maximum during the growth, followed by in stems and in leaves. Absorptive capacity in the whole plant for Cu, Zn, Pb and Cd exists extremely significant difference ( p Zn > Cu > Cd. The absorption in root is higher than in stems and in leaves ( p p > 0.05).

Copper Removal in Tequila and Ethyl Alcohol by Cementation

In this paper results of copper removal in ordinario and ethyl alcohol by cementation using an iron rod as a sacrifice anode are presented. Experiments were performed in ordinario containing copper without controlling pH and in an acetate buffer. Concentration before and after cementation were determined by atomic absorption spectroscopy. The highest removal efficiency of Cu (II) in ethyl alcohol and ordinario without buffer occurs at pHs of 4.8 and 3.3 respectively, with 49% removal in both cases. On the other hand, the highest removal percentage of Cu(II) in ethyl alcohol and ordinario at buffered conditions and pHs of 4.9 and 3.0 are 52.1 and 61.1% respectively, the major removal efficiency appears at more acidic pHs because iron has a major facility to oxidize in acidic pH.

Heavy Metal Removal from Shooting Range Soil by Hybrid Electrokinetics with Bacteria and Enhancing Agents

This study presents a method for heavy metal removal from a shooting range soil by a newly suggested hybrid technology. Active bioaugmentation was performed using Acidithiobacillus thiooxidans in the bioleaching step, and each test was sequentially combined with acid-enhanced and EDTA-enhanced electrokinetics. The results of the bioleaching processes indicated that S-oxidizing bacteria enhanced the mobility of heavy metals in the soil, based on their chemical forms. This process improved the final removal efficiencies of Cu and Zn in the hybrid electrokinetics. In the case of Pb, however, anglesite (PbSO(4)) has been easily formed in the bioleaching step from sulfate, a byproduct of S oxidation. Despite the potential negative effect on combining acid-enhanced electrokinetics, this problem was overcome by the application of an electrokinetic EDTA injection. Moreover, this method showed enhanced removal efficiency for Pb (92.7%) that was superior to that of an abiotic process. This hybrid method of EDTA-enhanced bioelectrokinetics demonstrated an adequate removal efficiency of heavy metals, especially Pb, with lower power consumption and eco-friendly soil conditions.

Extraction separation of Cu(II) and Co(II) from sulfuric solutions by hollow fiber renewal liquid membrane

Extraction separation of Cu(II) and Co(II) from sulfuric wastewater is studied with hollow fiber renewal liquid membrane (HFRLM) technique. The organic solution of LIX 984N in kerosene is used as the liquid membrane phase to selectively separate and concentrate Cu(II) from aqueous solution; and the extractant of CYANEX 272 is used as carrier to remove and concentrate Co(II) from aqueous solution. In the selective separation process, LIX 984N has good selectivity on Cu(II); the interactions among metal ions can be negligible; the pH in the feed aqueous solution has significant influence, while the influence of hydrogen ion concentration in the stripping phase is slight. The removal efficiency of Cu(II) increases with the increasing flow rate on lumen side, while decreases with the increasing flow rate on shell side. The results of lab-scale cascade experiments show that the HFRLM technique is a promising treatment method for simulated sulfuric wastewater containing copper and cobalt with separation factor higher than 100. The Cu(II) and Co(II) concentrations in the raffinate are lower than 0.50 mg L −1 and 1.0 mg L −1, respectively, which are both below the standard of wastewater discharge in China. Based on the surface renewal theory, resistance-in-series model and mass balance law, a corresponding mass transfer mathematical model is developed; and the calculated results are in good agreement with experimental data.

Removal of heavy metal ions from aqueous solution by electrocoagulation using a horizontal expanded Al anode

The performance of a batch cell with a horizontal expanded Al-anode in removing Cu2+ and Cr from a hexavalent chromium solution by electrocoagulation from separate solutions was examined. The effect of electrolysis time, current density, pH, initial pollutant concentration and NaCl concentration on the removal efficiency of Cu2+ and Cr has been investigated. The results revealed that as current density increases the removal efficiency of Cu2+ increases, while in the case of Cr it increases up to a certain limit, then remains approximately constant. The optimum pH is from 4 to 6 and 3.5 for Cu2+ and Cr removal, respectively. The removal efficiency of Cu2+ increases as NaCl increases, but in the case of Cr it decreases. COD measurements showed that a 66.67% reduction of COD has been obtained at the optimum conditions of Cu2+ removal. Energy consumption was calculated for both heavy metals at different current density and NaCl concentration. At the optimum condition an energy consumption of 43 kWh is required for the removal of one kg of Cu2+ ions; a value of 145 kWh is required for the removal of one kg of Cr. The difference in behavior between Cu2+ removal and Cr removal was explained on the basis that cathodic reduction of Cr6+ to Cr3+ which controls the rate of Cr removal.

Selection of adsorbents for treatment of leachate: batch studies of simultaneous adsorption of heavy metals

The simultaneous adsorption of copper (Cu), cadmium (Cd), nickel (Ni), and lead (Pb) ions from spiked deionized water and spiked leachate onto natural materials (peat A and B), by-product or waste materials (carbon-containing ash, paper pellets, pine bark, and semi-coke), and synthetic materials (based on urea-formaldehyde resins, called blue and red adsorbents) or mixtures thereof was investigated. The adsorbents that gave the highest metal removal efficiencies were peat A, a mixture of peat B and carbon-containing ash, and a mixture of peat A and blue. At an initial concentration of 5 mg/l for each metal, the removal of each species of metal ion from spiked water and spiked leachate solutions was very good (>90%) and good (>75%), respectively. When the initial concentration of each metal in the solutions was twenty times higher (100 mg/l), there was a noticeable decrease in the removal efficiency of Cu2+, Cd2+, and Ni2+, but not of Pb2+. Langmuir monolayer adsorption capacities, qm, on peat A were found to be 0.57, 0.37, and 0.36 mmol/g for Pb2+, Cd2+, and Ni2+, respectively. The order of metal adsorption capacity on peat A was the same in the case of competitive multimetal adsorption conditions as it was for single-element adsorption, namely Pb2+ > Cd2+ ≥ Ni2+. The results show that peat alone (an inexpensive adsorbent) is a good adsorbent for heavy metal ions.

Characterization of Manganese Oxide and the Adsorption of Copper(II) and Lead(II) Ions from Aqueous Solutions

The characterization and sorption properties of manganese oxide towards Cu(II) and Pb(II) ions from aqueous solution were investigated. Scanning electron microscope (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and infrared (IR) analyses were used to characterize the manganese oxide. Parameters affecting the adsorption of Cu(II) and Pb(II) ions, such as the adsorbent dosage, the ionic strength of the solution, the contact time, the solution pH, the initial metal ion concentration and the temperature, were investigated. The binding of Cu(II) and Pb(II) ions to manganese oxide was highly dependent on the pH of the solution, with the extent of adsorption increasing as the pH of the system increased. The uptake of both Cu(II) and Pb(II) ions was found to increase with temperature. Furthermore, the removal efficiency of Cu(II) and Pb(II) ions from aqueous solution increased with increasing adsorbent dosage and decreased with ionic strength. The adsorption equilibrium and adsorption kinetics of Cu(II) and Pb(II) ions onto manganese oxide were studied. The adsorption process was spontaneous and exothermic, with the order of affinity being Pb(II) > Cu(II). The same behaviour was observed during competitive adsorption, viz. adsorption from a binary solution of the ions concerned.

Extraction of heavy metal from sewage sludge using ultrasound-assisted nitric acid

The effects of nitric acid concentration and sonication time on the removal efficiencies of heavy metals from sludge were investigated. Nitric acid concentrations were varied from 0 to 0.65 M and sonication time from 0 to 20 min. The extracted metals Cu, Zn, and Pb were determined. The results indicated that the removal efficiencies of Cu, Zn, and Pb increased with increases in nitric acid concentration and sonication time. The optimal nitric acid concentration for heavy metals extraction was 0.325 M, while a maximal sonication time of 20 min resulted in maximal heavy metals removal efficiencies. The removal efficiencies of Cu, Zn and Pb reached 9.5%, 82.2%, and 87.3%, respectively, at the optimal concentration of nitric acid assisted by ultrasound for 20 min. Additionally, the residual contents of Zn and Pb in sludge met Chinese legal standards, while Cu was not significantly removed regardless of the nitric acid concentrations and sonication time. The order of heavy metal removal efficiencies was Pb > Zn > Cu. During heavy metal extraction, contribution proportions of ultrasonication and nitric acid to the extraction were 18–22% and 78–82%, respectively. Ultrasound alone was not effective enough to remove heavy metals from sludge and the role played by nitric acid predominated over that of ultrasound. However, ultrasound was synergistic with nitric acid when these were used together to extract heavy metals from sludge. Possible mechanisms of heavy metal extraction are also discussed.

UV/TiO2 and UV/TiO2/chemical oxidant processes for the removal of humic acid, Cr and Cu in aqueous TiO2 suspensions

The objective of this study was to investigate the treatment efficiency of UV/TiO2 and UV/TiO2/chemical oxidant processes for the removal of humic acid and hazardous heavy metals in aqueous TiO2 suspensions. The reaction rate (k) of humic acid and hazardous heavy metals by UV/TiO2 was higher than that of UV illumination alone or TiO2 alone. The removal efficiency for humic acid and Cr(VI) at acid or neutral pH values was higher than that at basic pH values. However, the removal efficiency for Cu(II) at acid pH values was smaller compared with that at neutral or basic pH values. The reaction rate (k) of humic acid and hazardous heavy metals in the TiO2 concentration range of 0.1–0.3 g l−1 increased with increasing TiO2 dosage. However, amounts higher than a TiO2 dosage of 0.3 g l−1 reduced the removal efficiency for humic acid and hazardous heavy metals because of the shielding effect on the UV light penetration in the aqueous solution caused by the presence of excessive amounts of TiO2. The addition of oxidants to the UV/TiO2 system showed an increase in degradation efficiency for the treatment of humic acid and hazardous heavy metals. The optimal concentration of oxidants was: H2O2 50 mg l−1, O3 20 g m−3 and K2S2O8 50 mg l−1, respectively. The degradation efficiency of UV/TiO2/oxidant systems for the removal of humic acid and hazardous heavy metals was much greater when H2O2 was used as the oxidant.

Application of ferrate(VI) in the treatment of industrial wastes containing metal-complexed cyanides: A green treatment

Ferrate(VI) was employed for the oxidation of cyanide (CN) and simultaneous removal of copper or nickel in the mixed/complexed systems of CN-Cu, CN-Ni, or CN-Cu-Ni. The degradation of CN (1.00 mmol/L) and removal of Cu (0.095 mmol/L) were investigated as a function of Fe(VI) doses from 0.3-2.00 mmol/L at pH 10.0. It was found that Fe(VI) could readily oxidize CN and the reduction of Fe(VI) into Fe(III) might serve efficiently for the removal of free copper ions. The increase in Fe(VI) dose apparently favoured the CN oxidation as well as Cu removal. Moreover, the pH dependence study (pH 10.0-13.0) revealed that the oxidation of CN was almost unaffected in the studied pH range (10.0-13.0), however, the maximum removal efficiency of Cu was obtained at pH 13.0. Similarly, treatment was carried out for CN-Ni system having the initial Ni concentration of 0.170 mmol/L and CN concentration of 1.00 mmol with Fe(VI) dose 2.00 mmol at various pH values (10.0-12.0). Results showed a partial oxidation of CN and partial removal of Ni. It can be observed that Fe(VI) can partially degrade the CN-Ni complex in this pH range. Further, Fe(VI) was applied for the treatment of simulated industrial waste/effluent waters treatment containing CN, Cu, and Ni.

Coupled removal of organic compounds and heavy metals by titanate/carbon nanotube composites

The objective of this study was to fabricate 1-dimensional (1-D) nanocomposite materials with high aspect ratios and specific surface areas for the coupled degradation of refractory organic compounds and heavy metals. The 1-D nanomaterials were composed of various ratios of carbon nanotubes (CNT) and titanate nanotubes (TNT) (CNT/TNT). Alkaline hydrothermal method was used to fabricate TNT under various hydrothermal conditions. The morphology changed from nanoparticles/nanosheets, nanotubes, nanowires and then to nanoribbon as the hydrothermal temperatures increased from 60 to 230 degrees C. In addition, the CNT/TNT nanomaterials have a good capability toward heavy metal adsorption. The Langmuirian maximum adsorption capacities of nanomaterials were in the range 83-124 mg/g for Cu2+ and 192-588 mg/g for Pb2+, which is superior to that of CNT. The removal efficiency of Cu2+ by CNT/TNT decreased when 40 mg/L MX5B was due to the complexation of MX5B with Cu2+. Results obtained in this study clearly show the 1-D CNT/TNT nanomaterials are a promising nano-adsorbent for coupled removal of organic as well as heavy metal ions in solution.