Plating Industry Wastewater Research Articles

A study of continuous-flow electrocoagulation process to minimize chemicals dosing in the full-scale treatment of plastic plating industry wastewater

A continuous-flow electrocoagulation unit was used to replace the existing chemical coagulation in plastic plating industry wastewater treatment plants, aiming to enhance pollutant removal and cost efficiency. This study was conducted at an on-site wastewater treatment plant, with the electrocoagulation process monitored for nine consecutive months. A novel electrocoagulation unit equipped with multi-rod helical systems (i.e., made of an iron anode and a stainless-steel cathode) was used in this study, with the treatment flow adjusted to optimize the operational costs. The results indicate that energy consumption can be maintained at 7200 kWh/month while achieving >99 % removal of heavy metals (Cr, Ni, and Cu), with removal rates of 78.64 ± 0.13 mg/L.day (Cr), 105.47 ± 0.07 mg/L.day (Ni), and 38.30 ± 0.09 mg/L.day (Cu). The chemical cost was reduced by approximately 50 %. Furthermore, an over 50 % reduction in sludge production was achieved, with the acid and alkaline by-products entirely recycled. Compared to the previously applied chemical coagulation, electrocoagulation can reduce operational costs from US$ 6.11 to US$ 2.87 per m3 of wastewater treated. These results confirm that electrocoagulation can be optimized and implemented to replace conventional chemical coagulation.

Enhanced Adsorptive Removal of Cr (VI) from Plating Industry Wastewater Using CoFe2O4/CTAB Magnetic Nanocomposites

Enhanced Adsorptive Removal of Cr (VI) from Plating Industry Wastewater Using CoFe2O4/CTAB Magnetic Nanocomposites

Removal of Copper (II) from Mining Waste Water by Adsorption onto Activated Carbons Produced from Hazelnut Shell

Mining wastewater is one of the most important environmental problems today because of the heavy metal ions they contain. Wastewaters containing heavy metal pollution are generally acidic waters with low BOI (Biochemical oxygen demand) value. Various processes such as mineral processing waste disposal, illegal mining, domestic waste disposal, and others result in the release of heavy metals into the waters. One of the heavy metals that cause problems in terms of environmental pollution is copper. Copper metal is commonly found in metal and metal plating industry wastewater. Although metal industry wastewater is low in quantity, they are toxic waste. For this reason, industrial wastewater must be treated before being discharged into the receiving environment. In this study, the amount of Cu in wastewater of the mining operation in Gümüşhane was determined. Heavy metal pollution was eliminated with an adsorbent produced from agricultural biowaste. It has been tried to determine the amount of adsorbent, contact time, and treatment efficiency of wastewater at different pHs of activated carbon produced by chemical activation. As a result, an average of 88.7% efficiency was obtained with activated carbon activated with KOH, while 22,4% copper removal efficiencies were obtained with raw material (hazelnut shell) used without activation. It was determined that the appropriate working pH was 5,0; the amount of adsorbent was 0.05 g and Qmax 121,2. As a result, in this study, very low-cost adsorbents were produced using waste hazelnut shells, and a biotechnological approach was proposed to clean copper-containing wastewater.

Feasibility assessment of humidification–dehumidification and adsorption water treatment processes for real-time treatment of plating industry wastewater

A plating solution is typically diluted because Zn-Ni-plated iron substrates with hydrophobic characteristics result in a larger amount of water drag-in from the preceding rinse than the plating solution drag-out. The diluted plating solution is discarded because of its reduced plating efficiency. However, its disposal can have substantial economic and environmental impacts. The aim of this study was to concentrate a diluted plating solution through the humidification–dehumidification (HDH) and adsorption water treatment (AWT) processes to assess its reusability in the electroplating process and establish the feasibility of these processes. The HDH product contained many contaminants (total dissolved solids > 521 ppm) such as heavy metals, chemical compounds, and ions. Moreover, the concentrated plating solution obtained using HDH did not satisfy the required standards in terms of plating efficiency and corrosion resistance. This was demonstrated by the hull cell test. In contrast, the AWT product showed a remarkable absence of contaminants, making it a suitable alternative to degreasing as a pre-treatment before electroplating. The hull cell test results obtained employing the concentrated plating solution derived from the AWT process indicated a 12 % increase in the plating efficiency and demonstrated effective corrosion resistance. Furthermore, the AWT process exhibited a low specific energy consumption (1.87 kWh/m3) compared with the HDH process (5.16 kWh/m3). To conclude, the AWT process has distinct advantages in terms of water quality, plating efficiency, and specific energy consumption. This establishes its effectiveness for treating plating solutions.

Degradation of 1,4-dioxane from water and plating industry wastewater using electrochemical batch and plug flow reactors

Degradation of 1,4-dioxane from water and plating industry wastewater using electrochemical batch and plug flow reactors

Removal of Ni(II) and Cr(VI) Ions From Electroplating Wastewater Using Ferrous Sulfate

Background: In this study, the ferrous sulfate was used to remove Cr(VI) and Ni(II) ions from a real Ni-Cr plating industry wastewater. Methods: This is an applied study. The type of sampling was composite by three 5 L containers. Wastewater chemical and physical characteristics were measured in accordance with the standard methods. The concentration of un-removed metal ions was estimated by ICP-OES. The Jar test was used to carry out the chemical coagulation experiment. The results indicated that the rate of removal depended on the pH of 1.5-11, the diverse contact time of 30-120 min, and the coagulant measurement ranging from 0.5-2 g/l. Results: The optimum removal of Cr(VI) ions was observed at a pH of 7 up to 83.88% in 0.5 g/l of coagulant for 40 min. While the optimum removal of Ni(II) ions was found at a pH of 5 up to 56.33 % in 0.5 g/l of coagulant for 40 min. The scanning electron microscopy results revealed the difference between the coagulant surface while coagulation. Also, the Energy-Dispersive X-ray spectroscopy (EDX) analysis showed the presence of Cr(VI) and Ni(II) ions on the surface of the ferrous sulfate after coagulation. Conclusion: Ultimately, the results indicated that ferrous sulfate could be an operative chemical coagulant to remove Cr(VI) and Ni(II) ions from the plating industry wastewater, especially for Cr(VI) particles. The results of this study can be a useful guide to the real plating industry wastewater treatment operators.

Competitiveness in removing copper, zinc and chromium trivalent in plating industrial effluent by using hydroxide precipitation versus sulphide precipitation

Plating industry wastewater is one of the processes that may contain various types of heavy metals. The most common heavy metals that mostly found are copper, nickel, cadmium, chromium, silver, zinc, and lead. In this study, three types of metals which are copper, zinc and chromium trivalent were removed using hydroxide precipitation and sulphide precipitation. Both performances of the method were observed and compared. A jar test was used to determine the optimum pH, coagulant dosage and precipitant dosage. The coagulant and precipitant used in this experiment was ferric chloride (FeCl3), poly aluminium chloride (PAC), sodium hydroxide (hydroxide precipitant) and sodium sulphide (sulphide precipitation) respectively. In order to remove chromium trivalent, sodium metabisulfite was used to reduce chromium hexavalent to chromium trivalent. Based on the result, hydroxide precipitation can remove 86.61% of copper, 99.81% of zinc and 99.99% of chromium trivalent. While, for sulphide precipitation, 93.91% of copper, 99.37% of zinc and 99.99% of chromium trivalent were removed. Therefore, sulphide precipitation can remove better mixed heavy metals, thus it also produces less total suspended solid compared to hydroxide precipitation.

Decomplexation of Cu(II)/Ni(II)-EDTA by ozone-oxidation process.

In this study, ozone-oxidation was used to treat synthetic chemical plating solution containing Cu(II)/Ni(II)-EDTA solution to realize the purpose of decomplexation. The effects of solution pH, initial concentration of Cu(II)/Ni(II)-EDTA, the molar ratio of EDTA to Cu(II)/Ni(II), and the coexistence of Cu(II)/Ni(II) on their removal efficiencies were investigated. The degradation of EDTA-Cu(II) and EDTA-Ni(II) were mainly attributed to OH oxidation, and the removal rates of Cu(II)/Ni(II) depend on the complete decomplexation. The removal rates of Cu(II) and Ni(II) was affected by the pH of solution, and the optimal pH was found to be 7-9; nevertheless, their removal rates can still be up to 90% even in acidic pHs of 3~5. When the molar ratio of EDTA to Cu(II)/Ni(II) increased from 1:1 to 3:1, the kinetics of metal ion removal rate declined from 0.0788 and 0.1139 min-1 to 0.0250 and 0.0271 min-1. The synergistic effect was found in the Cu(II)/Ni(II) blended system due to the higher catalytic capability and the lower complexation affinity toward EDTA for Ni(II). In summary, ozone oxidation can be considered as an effective technology to realize the complete decomplexation of Cu(II)/Ni(II)-EDTA that contained in chemical plating industry wastewater. Graphical Abstract.

Removal of F–53B as PFOS alternative in chrome plating wastewater by UV/Sulfite reduction

Chrome mist suppressants are key chemicals used in the chrome plating industry to reduce exposure of workers by inhalation to airborne chromic acid pollution. Perfluoroalkyl sulfonated compounds are excellent mist suppressants, thanks to their chemical stability and surface activity. Therefore, despite mounting evidence for their persistence, bioaccumulation and toxicity, it is likely that such chemicals will continue to be used for the foreseeable future because of their importance and lack of alternatives. The present study is aimed at assessing the feasibility of advanced reduction as an effective technology to treat chrome plating industry wastewater. In particular, wastewater containing a chlorinated polyfluorinated ether sulfonate (i.e. F–53B), an alternative to perfluorooctanesulfonate (PFOS) used to prepare chrome mist suppressant in China, was treated by UV-activated sulfite. Results demonstrates that in ultrapure water F–53B can be easily degraded within 1 min—much faster than PFOS. Stoichiometric fluoride recovery was also achieved, confirming significant defluorination of the pollutant. Such superior reducibility was due to the presence of chlorine atoms, as corroborated by quantum chemical calculations. F–53B degradation was also achieved in chrome plating industrial wastewater, which yielded results were slower than those achieved in the laboratory nonetheless obtained complete abatement within 60 min. These results suggest that the proposed advanced reduction process is one of the safest options to control PFAS discharge in the environment and reduce the related risks to ecosystems.

Palladium Recovery through Membrane Capacitive Deionization from Metal Plating Wastewater

The potential application of membrane capacitive deionization (MCDI) for recovery of palladium (Pd) ions from catalyst solution wastewater generated from the plating industry was investigated in this study. Several major issues were explored in this work to verify the suitability of MCDI for Pd recovery from a practical perspective: adsorption and desorption efficiencies, desorption mechanisms into high concentration of Pd concentrate, and its sustainability in long-term operation. The lab-scale MCDI operation achieved satisfactory and highly competitive Pd removal (99.07–99.94% removal with 1.42–1.52 of Pd selectivity over ammonium ions) showing that Pd can be effectively collected from plating industry wastewater. A high concentration of Pd concentrate (64.77 and 919.44 mg/L of Pd from the 10 and 100 mg/L Pd containing catalyst solution, respectively) was obtained through successive five operation cycles of adsorption/desorption phases. However, it is significant to note that the desorption efficiency w...

PENGARUH JENIS PELARUT DAN SENYAWA PENGEMBAN TERHADAP EFISIENSI PEMISAHAN LOGAM PERAK DENGAN TEKNIK MEMBRAN CAIR BERPENDUKUNG

Silver metal found in the metal plating industry wastewater, industrial process photography and X-ray film process. Wastes that still lack the metallic ions of silver if thrown in the water without further treatment would endanger the life of organisms, mainly bacteria, plants and living things, as silver metal is a metal that is toxic in dissolved form. One separation technique can be used with supported liquid membrane (SLM) technique. This study aimed to identify the type of solvent and carrier compound to percent transport of silver metal from the feed phase to phase receivers with SLM techniques. This type of research used in this study was an experimental research in the laboratory. Percent transport of metal ions Ag + with techniques SLM had done by varying the type of solvent was n-hexane, kerosene, toluene and chloroform to dissolve the compound carrier TBP and D2EHPA with each concentration 1 M. The concentration of the metal ions Ag+ in phase receiver after separation techniques SLM was measured by Atomic Absorption Spectrophotometer (AAS) at a wavelength of 328.1 nm, then the calculated percent metal Ag+ ion transport. Based on the results showed that the percent of the silver metal transport centipede on the use of solvent n-hexane and chloroform, with transport by 33.9% percent. While the percent of the highest transport to the use of compounds that was using the carrier of carrier compound TBP, with transport by 33.9% percent.

Electrochemical decomposition of fluorinated wetting agents in plating industry waste water

Electrochemical decomposition of fluorinated surfactants (PFAS, perfluorinated alkyl substances) used in the plating industry was analyzed and the decomposition process parameters optimized at the laboratory scale and production scale of a 500-liter reactor using lead electrodes. The method and system was successfully demonstrated under production conditions to treat PFAS) with up to 99% efficiency in the concentration range of 1,000-20,000 μg/l (1 ppm-20 ppm). The treatment also reduced hexavalent chromium (Cr(6+)) ions to trivalent chromium (Cr(3+)) ions in the wastewater. If the PFAS-containing wastewater is mixed with other wastewater streams, specifically from nickel plating drag out solution or when pH values >5, the treatment process is ineffective. For the short chain PFAS, (perfluorobutylsulfonate) the process was less efficient than C6-C8 PFAS. The process is automated and has safety procedures and controls to prevent hazards. The PFAS were decomposed to hydrogen fluoride (HF) under the strong acid electrochemical operating conditions. Analytical tests showed no evidence of organic waste products remaining from the process. Conventional alternative PFAS removal systems were tested on the waste streams and compared with each other and with the-E-destruct (electrochemical oxidation) process. For example, ion exchange resin (IX resin) treatment of wastewater to complex and remove PFAS was found to be seven times more efficient when compared to the conventional activated carbon absorption (C-treat) process. However, the E-destruct process is higher in capacity, exhibits longer service life and lower operating costs than either IX or C-treat methods for elimination of PFAS from these electroplating waste streams.

TREATMENT OF WASTEWATER FROM CHROME PLATING INDUSTRY BY ION EXCHANGE METHOD

In the present work an attempt has been made to evaluate the efficiency of removal Cr(VI) from chrome plating industry wastewater by using fresh and reconditioned strong base anion exchanger Tulsion A-27(MP). The Experimental data is evaluated by plotting breakthrough curves and by employing Bohart-Adams Model. The maximum removal (80%) of Cr(VI) from plating wastewater is obtained at 14cm column bed height and flowrate 1mL/min for 1144.39mg/L of influent Cr(VI) concentration. The breakthrough curves for reconditioned and fresh resins indicates that breakthrough occurs early with decrease in bed height, increase in flow rate and influent Cr(VI) concentration. Regeneration of exhausted resin is also studied by using 2M NaCl and 2M HCl.

Optimization of Nickel Removal from Electroless Plating Industry Wastewater using Response Surface Methodology

Optimum pH and coagulant dosage for chemical precipitation in wastewater treatment plants is conventionally obtained through repeated jar test. In this research, optimization of the performance of polyacrylamide in the treatment of industrial wastewater was carried out using response surface methodology. The individual linear and quadratic effect of coagulant dosage and pH on the degree of removals of nickel, total suspended solids, Chemical Oxygen Demand and turbidity were investigated. The optimum pH and polyacrylamide dosage were found to be 10.5 and 1.6 ml/L respectively and the optimum percentage nickel removal was 96.9%. The model used in predicting the precipitation process gave a good fit with the experimental variables and hence the suitability of response surface methodology for the optimization of polyacrylamide performance.

The potential of Sedum alfredii Hance for the biosorption of some metals from synthetic wastewater

The capacity of a terrestrial Zn/Cd hyperaccumulator Sedum alfredii Hance to purify water polluted by Zn, Cd, Cu and Pb along with their removal pathway was investigated. S. alfredii Hance was grown in synthetic wastewater in 2.5-L capacity containers contaminated with (mg L −1) 19.20 Zn, 11.24 Cd, 3.27 Cu and 0.53 Pb, respectively. The supplied metal concentrations were comparable with those in plating industry wastewater. After a growth period of 7 days the average removal rates for Zn, Cd, Cu and Pb, were 94.07%, 82.33%, 96.03% and 69.61% respectively. Both root surface adsorption and absorption contributed to metal uptake. Root surface adsorption accounted for 67.74%, 24.03%, 66.53% and 70.77% of the total respective Zn, Cd, Cu and Pb, removal by S. alfredii. Addition of heavy metals stimulated the growth of S. alfredii over the control (without any addition of heavy metals) that might cause enhanced metal removal from wastewater. These results indicated promising potential of S. alfredii for remediation of a mixture of heavy metals containing wastewater. Rhizospheric microorganisms, root exudates and metal adsorption on the root surface of S. alfredii might be possible contributors in phytoremediation of Zn, Cu and Pb from wastewater.

Organic matter and heavy metal removals from complexed metal plating effluent by the combined electrocoagulation/Fenton process

In the present study, the treatment of metal plating wastewater containing complexed metals originating from the nickel and zinc plating process by electrocoagulation (EC) using stainless steel electrodes was explored. In order to improve the organic matter removal efficiency, the effect of H(2)O(2) addition to the electrocoagulation (the combined EC/Fenton process) application was investigated. For this purpose, a wide range of H(2)O(2) concentrations varying between 15 and 230 mM was tested. All EC and EC/Fenton processes were performed at an initial pH of 2.6 and at an optimized current density of 22 mA/cm(2). Although up to 30 mM H(2)O(2) addition improved the EC process performance in terms of organic matter abatement, the highest COD and TOC removal efficiencies were obtained for the combined EC/Fenton process in the presence of 20 mM H(2)O(2). Nickel and zinc were completely removed for all runs tested in the present study after pH adjustments. At the optimized operation conditions, the combined EC/Fenton process proved to be an alternative treatment method for the improvement of organic matter reduction as well as complexed metal removal from metal plating industry wastewater.

Removal of copper(II) by adsorption onto peanut hull carbon from water and copper plating industry wastewater

Activated carbon prepared from peanut hull (PHC), an agricultural waste by-product, has been used for the adsorption of Cu(II) from aqueous solution. The adsorption obeyed Langmuir adsorption isotherm. The applicability of Lagergren kinetic model has also been investigated. Quantitative removal of Cu(II) from a solution containing 20 mg/L Cu(II) by 0.9 g PHC per litre was observed in the pH range 4.0 to 10.0. The suitability of PHC for treating copper plating industry wastewater was also testea. A comparative study with a coal based commercial granular activated carbon (GAC) showed that the adsorption capacity (Q o) of PHC was 18 times larger than that of GAC.

Removal of nickel(II) from aqueous solution and nickel plating industry wastewater using an agricultural waste: Peanut hulls

Activated carbon prepared from peanut hulls (PHC), an agricultural waste by-product, has been used for the adsorption of Ni(II) from aqueous solution. The process of uptake obeys both Freundlich and Langmuir adsorption isotherms. The applicability of Lagergren kinetic model has also been investigated. Quantitative removal of Ni(II) from 100 mL aqueous solution containing 20 mg/L Ni(II) by 85 mg PHC was observed over a pH range of 4.0 to 10.0. The suitability of PHC for treating nickel plating industry wastewater was also tested. A comparative study with a commercial granular activated carbon (GAC) showed that PHC is 36 times more efficient compared to GAC based on Langmuir adsorption capacity (Q O).

Recycling of ‘waste’ FE(III)/CR(III) hydroxide for the removal of nickel from wastewater: Adsorption and equilibrium studies

Effects of Ni(II) concentration, agitation time, temperature and pH on adsorption of Ni(II) on Fe(III)/Cr(III) hydroxide, a waste by-product from fertilizer industry, have been investigated. The percent adsorption increased from 55 to 69% with increase in temperature from 20 to 40°C and from 32 to 77% with increase in pH from 3.7 to 7.5 and from 38 to 79% with decrease in Ni(II) concentration from 100 to 25 mg/L. The equilibrium data fit well with the Langmuir isotherm and the adsorption capacity was found to be 21.0 mg/g at 30°C. Thermodynamic parameters such as free energy change (ΔG°), enthalpy change (ΔH°) and entropy change (ΔS°) were evaluated. The adsorption rate constant was higher at lower concentration of Ni(II) and at higher temperature. Desorption studies show that 70% of Ni(II) can be desorbed from the adsorbent at pH 4.0. The adsorbent was tested using nickel plating industry wastewater and the maximum percent removal was 97.

Waste Fe(III)/Cr(III) hydroxide as adsorbent for the removal of Cr(VI) from aqueous solution and chromium plating industry wastewater

Fe(III)/Cr(III) hydroxide, a waste material from the fertilizer industry, has been used for the adsorption of Cr(VI) from aqueous solution, over a range of initial metal ion concentrations (5–30 mg litre −1), agitation times (1–180 min), adsorbent dosages (100–1200 mg per 50 ml), temperatures (24, 29 and 38°C) and pH values (4·5–10). The adsorption of Cr(VI) increased with the initial concentration of Cr(VI) and with temperature. The process of uptake follows both the Langmuir and the Freundlich isotherm models. The applicability of Lagergren and empirical kinetic models has also been investigated. Almost quantitative removal of Cr(VI) at 10 mg litre −1 in a 50-ml solution by 500 mg of adsorbent was found at an equilibrium pH of 5·6. The efficiency of chromium removal was also tested using wastewater from the chromium plating industry.