Electroless Nickel Plating Wastewater Research Articles

Synthesis and properties of multi-porous multi-doped nano-Na3V2(PO4)3@C materials from electroless nickel plating wastewater

Synthesis and properties of multi-porous multi-doped nano-Na3V2(PO4)3@C materials from electroless nickel plating wastewater

Highly efficient nickel recovery from industrial wastewater via synergistic electrodeposition and electrocatalytic oxidation technique

This study was conducted to address water pollution concerns entwined with electroless nickel plating (ENP) industry. Its principal endeavor centers on the development and application of an innovative single-compartment technique to proficiently treat spent ENP baths. The research demonstrated the recovery of Nickel (Ni) from wastewater through synergistic interactions between electrocatalytic oxidation and electrodeposition processes. Electrochemical tests used a direct current power supply in constant current mode, with the positive pole on IrO2/Ti mesh and negative pole on stainless steel. Zero-valent nickel recovered on the electrodes was conclusively identified via SEM, XRD, and EDS analyses. This work carefully examined the impact of initial pH, initial Ni ion concentration, and current density (CD) on electrochemical recovery efficiency. The findings suggest that higher current densities positively influence the Ni recovery ratio. Additionally, through meticulous experiments, the viability of this approach for treating spent ENP baths has been confirmed. An impressive 98.88% recovery of Ni was achieved under specific conditions: CD 4.5 mA cm−2, experimental time 180 min, pH 4.5, electrodes spacing 1.5 cm, temperature 55 °C, and a dilution factor 10 times. The study demonstrated the process for Ni recovering from ENP wastewater through direct oxidation and subsequent decomposition, leading to liberation of free Ni ions. The recovered substance, identified as zero-valent nickel, adheres to the electrodes. The method employed in this research is described by its cost-effectiveness, user-friendliness, and low energy consumption. As a result, this study makes valuable contributions to both wastewater remediation and the sustainable utilization of Ni resources.

Efficient simultaneous removal of nickel, phosphorus and COD from electroless nickel plating wastewater by three dimensional electrodialytic system

The simultaneous removal of nickel (Ni), phosphorus (P) and chemical oxygen demand (COD) from electroless Ni plating (ENP) wastewater by a three-dimensional electrodialysis (3D ED) system with graphite as the third electrode was investigated in this study. Compared to conventional two-dimensional electrodialysis (2D ED) system a significantly higher removal efficiency of complexed Ni, P and COD was achieved. The optimal process conditions were determined as dilution factor of 20, voltage of 20 V, treatment time of 10 h and particle electrode addition of 3 %, with removal rates of 95.8 %, 97.7 %, and 91.8 % for Ni2+, total phosphorus (TP) and COD, respectively. The decomplexed Ni2+ was recovered in the form of Ni(OH)2. Additionally, the mechanisms of enhanced ENP wastewater treatment was discussed and analyzed through SEM-EDS and XPS on solid and liquid products prior to and after treatment. This study provides crucial theoretical and practical support for the application of electrochemical technology in the treatment of ENP wastewater. It also offers new insights for achieving resource-efficient wastewater treatment and environmentally friendly electroplating industries.

Performance and oxidation mechanism of VUV photo–Fenton in simultaneous removal of Ni-EDTA and hypophosphite: decomplexation, low-valent phosphorous oxidation and DFT calculation

The photo–Fenton process offers a promising alternative for the oxidation of complex heavy metals. However, the potential influence of coexisting substrates may be overlooked. The •OH radicals generated in the photo–Fenton process ensure superior oxidation ability. In this study, we used a vacuum ultraviolet (VUV) light-assisted photo–Fenton (VPF) process to explore its performance in the synergistic oxidation of Ni-ethylenediaminetetraacetic acid (EDTA) and coexisting hypophosphite, typical pollutants in electroless nickel plating (ENP) wastewater. Based on electron spin resonance (ESR) and DMSO-probing results, •OH was the predominant reactive oxygen species, and VPF possessed the highest •OH concentration compared to other photochemical processes under identical conditions (pH, Fe, H2O2). Enhanced •OH generation in VPF was attributed to various photochemical reactions, including photo–Fenton, UV/H2O2, and VUV/H2O. Consequently, VPF exhibited efficient Ni-EDTA decomplexation and hypophosphite oxidation. Notably, the evolution and rate-limiting steps during hypophosphite oxidation were demonstrated by experimental results and density functional theory calculations. Hypophosphite was initially oxidized to phosphite, which subsequently oxidized to phosphate. The oxidation of phosphite could be considered the rate-limiting step as it exhibits higher energy barriers than hypophosphite oxidation. Adequate •OH generation in the VPF process could overcome this energy barrier, indicating its potential for application in pollutant removal and resource recovery from ENP wastewater.

Recovery of nickel, phosphorus and nitrogen from electroless nickel-plating wastewater using bipolar membrane electrodialysis

Electroless nickel-plating (ENP) wastewater is challenging to treat because of its complex composition. This study used bipolar membrane electrodialysis (BMED) to remove and recover Ni2+, NH4+, total phosphorus (TP) and NO3− from ENP wastewater. The results show that current density significantly affects ion removal and recovery, current efficiency, specific energy consumption and ion migration velocity. When the current density was 20 mA/cm2, the removal ratios of Ni2+, NH4+, TP and NO3− were 100%, 98.6%, 99.3% and 100% after 14 h, respectively, and their recovery ratios were 92.6%, 75.5%, 94.5% and 90.6%, respectively. The removal kinetics analysis showed that the removal of Ni2+, NH4+, TP and NO3− was consistent with the zero-order kinetics process. The current efficiency variated from 42.5% to 39.0% and 37.7%, and the specific energy consumption decreased from 1.67 to 1.38 and 1.32 kW h/mol with the equipped wastewater compartments increased from one to two and three in a BMED system. Post treatment, Ni2+ was recovered as Ni(OH)2, with a purity of 82.6% (commercial Ni(OH)2 purity = 90%). TP was recovered as struvite with a purity of 95.3%, and the physicochemical properties of the obtained struvite were similar to commercial struvite. NH4+ was recovered as (NH4)2SO4 and NH3•H2O. Therefore, BMED is an effective method to recover Ni2+, TP and NH4+ from ENP wastewater.

Cu-mediated optimization of PbO2 anodes for electrochemical treatment of electroless nickel plating wastewater

Effective removal of Ni(Ⅱ)-organic complexes from electroless nickel plating wastewater remains a challenge by conventional industrial effluent treatment processes. In this study, electrochemical oxidation using a PbO2 anode is proposed for effective decomplexation of Ni-organic complexes. The electrode quality and electrocatalytic capability of the PbO2 anode is shown to be greatly affected by the nature of the PbO2 active layer that is formed during the electrodeposition process with the current density, cathode material and electrolyte constitutions all exerting an influence on the Pb deposition behavior. Our investigations reveal that the presence of Cu2+ in the electrolyte can precisely control the amount of elemental Pb formed with Pb cathodic reduction and deposition prevented as a result of preferential Cu0 deposition. The doping of PbO2 with Cu significantly improved the morphology and electrocatalytic performance of the PbO2 deposit. Ni-citrate and TOC removal percentages of 83 % and 55 % respectively were achieved with the optimal Cu-doped PbO2 anode with 73 % of the Ni recovered at the cathode at a relatively low specific energy consumption of 12.7 kWh m−3. A possible mineralization pathway of Ni-citrate by the PbO2 anodic oxidation process is proposed.

Recovery of nickel from electroless nickel plating wastewater based on the synergy of electrocatalytic oxidation and electrodeposition technology.

Nickel exists primarily as a stable complex in electroless nickel plating wastewater, and the Ni recovery from it cannot be achieved solely through electrodeposition. As the electrocatalytic oxidation has excellent oxidation potential to break down the complex, an efficient and stable electrochemical system using the synergy of electrocatalytic oxidation and electrochemical deposition technology was developed for the recovery of nickel from electroless nickel plating wastewater. In the present study, the effects of initial pH, current density, and initial nickel ion concentration on the treatment performance of the electrochemical system was investigated. The highest Ni recovery (94.84%) and total organic carbon removal (63.94%) were achieved at a current density of 83.3mA/cm2 , initial pH of 3.0, and initial Ni concentration of 0.01 M. At the same time, the recovered nickel product was confirmed by scanning electron microscopy, energy dispersive X-ray, X-ray powder diffraction, and X-ray photoelectron spectroscopy. Furthermore, the electrochemical system displayed good stability and economic benefits, thereby suggesting its excellent application potential for the treatment of electroless nickel plating wastewater. PRACTITIONER POINTS: An efficient and stable electrochemical system was developed for the recovery of nickel from electroless nickel plating wastewater. In an acidic medium, the nickel recovery rate and TOC removal ratio were 94.84% and 63.94%, respectively. The system displayed good stability, thereby suggesting its excellent application potential for the treatment of nickel plating wastewater.

Intense removal of Ni (Ⅱ) chelated by EDTA from wastewater via Fe3+ replacement–chelating precipitation

Efficient removal of Ni (Ⅱ) chelated by ethylenediaminetetraacetic acid (EDTA) from wastewater remains an important but challenging environmental problem. Therefore, a novel strategy of Fe3+ replacement–chelating precipitation was proposed to remove Ni (Ⅱ) chelated by EDTA from simulated Ni-EDTA wastewater and real electroless nickel plating wastewater. The strategy was proved to be thermodynamically feasible by DFT calculation. Regardless of the simulated Ni-EDTA wastewater or the real electroless nickel plating wastewater, the residual nickel in the wastewater was less than 0.1 mg/L that satisfied the discharge standard after being treated under optimal conditions using this strategy. Moreover, the strong acidity and Fe3+ could increase the proportion of free Ni2+ in Ni-EDTA wastewater, thereby enhancing the Ni removal efficiency. Additionally, the total amount of EDTA in wastewater was basically unchanged, since the structure of EDTA was not destroyed by this strategy, while its chemical form changed from Ni-EDTA complex to Fe3+-EDTA complex. Furthermore, the mechanism was systematically studied by electronic structure analysis, solution chemistry, UV-Vis spectral, FT-IR spectral and X-ray photoelectron spectroscopy. At last, this strategy is a promising approach and it can provide a reference for the treatment of other similar heavy metal wastewater.

Decomplexation of Ni(II)-citrate and recovery of nickel from chelated nickel containing electroplating wastewater by peroxymonosulfate with nickel

In this work, Ni(II) was used as peroxymonosulfate (PMS) activator for decomplexation of Ni(II)-citrate, and subsequently applied for the decomplexation of chelated nickel in the electroless nickel plating wastewater. Effect of the co-existed substances (HCO3−, HPO32−, H2PO2−, and P2O74−) on the decomplexation of Ni(II)-citrate were evaluated. Interestingly, except for H2PO2−, the presence of HCO3−, HPO32−, and P2O74− enhanced the decomplexation efficiency of Ni(II)-citrate via promoting the decomposition of PMS. Based on the radical quenching experiments and electron spinning resonance (ESR) spectra analysis, OH, SO4‐, and 1O2 were the primary reactive species involved in the decomplexation reaction process. Furthermore, after the decomplexation of the electroless nickel plating wastewater by PMS, the recovery of nickel was successfully achieved via adsorption coupled with electrodeposition, and 93.1% nickel recovery could be accomplished with initial Ni(II) eluent concentration of 32.5 g/L. Therefore, this study provides a green and promising approach for the application of advanced oxidation processes based on PMS activation, and has the potential to convert recoverable resources into value-added products from electroplating wastewater.

Electrochemical Ni-EDTA degradation and Ni removal from electroless plating wastewaters using an innovative Ni-doped PbO2 anode: Optimization and mechanism

In this work, a novel Ni-doped PbO2 anode (Ni-PbO2) was prepared via a co-electrodeposition method and used to remove Ni-ethylenediaminetetraacetic acid (Ni-EDTA) from solutions typical of electroless nickel plating wastewater. Compared with a pure PbO2 electrode, Ni doping increased the oxygen evolution potential as well as the reactive surface area and reactive site concentration and reduced the electron transfer resistance thereby resulting in superior Ni-EDTA degradation performance. The 1% Ni-doped PbO2 electrode exhibited the best electrochemical oxidation activity with a Ni-EDTA removal efficiency of 96.5 ± 1.2%, a Ni removal efficiency of 52.1 ± 1.4% and an energy consumption of 2.6 kWh m−3. Further investigations revealed that 1% Ni doping enhanced both direct oxidation and hydroxyl radical mediated oxidation processes involved in Ni-EDTA degradation. A mechanism for Ni-EDTA degradation is proposed based on the identified products. The free nickel ion concentration initially increased as a result of the degradation of Ni-EDTA complexes and subsequently decreased as a consequence of nickel electrodeposition on the cathode surface. Further characterization of the cathode deposits by X-ray diffraction and X-ray photoelectron spectra indicated that the deposition products were a mixture of Ni0, NiO and Ni(OH)2 with elemental Ni accounting for roughly 80% of the deposited nickel. Results of this study pave the way for the application of anodic oxidation processes for efficient degradation of Ni-containing complexes and recovery of Ni from nickel-containing wastewaters.

Decomplexation removal of Ni(II)-citrate complexes through heterogeneous Fenton-like process using novel CuO-CeO2-CoOx composite nanocatalyst.

A novel CuO-CeO2-CoOx nanocatalyst was prepared for heterogeneous Fenton-like reaction to break the Ni2+-chelate into free Ni2+ in electroless nickel plating wastewater, followed by separation of Ni2+ in an insoluble form. The composite nanocatalysts prepared by co-precipitation method were characterized by XRD, TEM, and XPS, et al. Its catalytic activity as Fenton-like reagent was evaluated by the removal efficiency of Ni(II)-citrate after decomplexation and postprecipitation treatment. Subsequently, the effects of operating parameters on the decomplexation efficiency of the nanocatalysts were investigated including calcination temperature of catalysts, H2O2 concentration, catalyst dosage, initial pH and reaction temperature. Under optimized condition, the Ni(II)-citrate complexes (C0 = 1.0 mM) achieved the complete decomplexation (>99.9%) within 60-min reaction using 0.3 g/L of CuO-CeO2-CoOx calcined at 450 °C and 75 mM of H2O2 at pH 3.0 under 50 °C of reaction. Then, Ni2+ after decomplexation could be completely removed by the subsequent precipitation at pH 11.0. In addition, the life test of CuO-CeO2-CoOx catalyst indicated that, after recycled 10 times, its activity for decomplexation of Ni(II)-citrate decreased no more than 8%. As a result, this new heterogeneous Fenton-like process is promising for decomplexation and purification of electroless nickel plating wastewater as a sludge reduction technology.

Environmental impacts assessment of industrial wastewater treatment system using electroless nickel plating and life cycle assessment approaches

Wastewater treatment systems have been designed to minimize the environmental impacts of discharging untreated wastewater in natural aquatic systems. Different wastewater treatment options have different performance characteristics and different direct impacts to the environment. The main aim of this study is to assess and quantify the environmental impacts of an electroless nickel plating wastewater treatment plant in Skudai, Johor Bahru, Malaysia. A life cycle assessment method, based on the international organization for standardization 14040 series framework, was used to assess the environmental impacts of the selected wastewater treatment plant. The ReCiPe life cycle impact assessment method attached to GaBi 4 software was used to assess the environmental impact of the selected industrial wastewater treatment plant. The results show that the existing chemical treatment process had the highest environmental impacts in terms of climate change with 1552.89 kg of CO2 and terrestrial acidification of 5.79 kg SO2 equivalent compared to the physical and biological treatment processes. Hence, two different scenarios, one utilizing chitosan and the other wet air oxidation (WAO) process, were formulated to reduce the environmental impacts of the conventional chemical wastewater treatment process. The impacts on the climate change using chitosan and WAO scenarios were both seen to have less than 110 kg CO2-equivalent emissions compared to the existing chemical process.

Solvent extraction of nickel ions from electroless nickel plating wastewater using synergistic green binary mixture of D2EHPA-octanol system

A study on the synergistic green solvent extraction of nickel ions from real electroless nickel plating wastewater using an organic phase containing a binary mixtures of Di (2-ethylhexyl) phosphoric acid (D2EHPA) and octanol in palm oil was conducted. The effects of diluent composition, synergist, carrier and stripping agent types and its concentrations were experimentally investigated and the optimum conditions were determined. Results revealed that both D2EHPA and octanol acted as a carrier and synergist, respectively. A significant synergistic effect occurred when the octanol helped destroy the dimer structure of D2EHPA for cation exchange mechanism with nickel ions, hence improving the nickel ions extraction up to 90% with the maximum distribution ratio of 8.8 under optimum condition of 0.7M D2EHPA and 15% (v/v) octanol in palm oil. Afterwards, the stripping experiment showed that nickel ions could be recovered from the loaded mixture of carrier using 1.0M nitric acid solutions. Besides, the slope analysis method showed that the nickel ions were extracted from weak acidic electroplating feed solution as nickel-D2EHPA-octanol complex and recovered as nickel nitrate complex in the stripping phase. Thus, it can be concluded that the green synergistic formulation containing binary mixtures of D2EHPA-octanol system is one of the promising approaches as well as a green and efficient separation method for nickel ions extraction from the real electroless nickel plating wastewater.

Decorating Waste Cloth via Industrial Wastewater for Tube‐Type Flexible and Wearable Sodium‐Ion Batteries

To turn waste into treasure, a facile and cost-effective strategy is developed to revive electroless nickel plating wastewater and cotton-textile waste toward a novel electrode substrate. Based on the substrate, a binder-free PB@GO@NTC electrode is obtained, which exhibits superior electrochemical performance. Moreover, for the first time, a novel tube-type flexible and wearable sodium-ion battery is successfully fabricated.

A sensing behavior synergistic liquid–liquid extraction and spectrophotometric determination of nickel(II) by using 1-(2ˊ,4ˊ-dinitro aminophenyl)-4,4,6-trimethyl-1,4-dihydropyrimidine-2-thiol: Analysis of foundry and electroless nickel plating waste water

ABSTRACTWe report the sensing behavior of liquid–liquid extraction of nickel(II), which has been selectively determined from contaminated water samples by a simple UV-visible spectrophotometer. The method is based on synergistic extraction of nickel(II) by 1-(2ˊ,4ˊ-dinitro aminophenyl)-4,4,6-trimethyl-1,4-dihydropyrimidine-2-thiol [2ˊ,4ˊ-dinitro APTPT] with pyridine. Nickel(II) reacts with 2ˊ,4ˊ-dinitro APTPT and forms a green-colored complex at pH 9.2. In addition, the Ni(II) ions were detected with the naked eye with the ligand. The absorbance of the coloured complex was measured at 660 nm and the colored complex is stable for more than 48 h even in the presence of other competing ions. The system obeyed Beer’s law in the concentration range of 5–50 μg mL−1 of nickel(II) and the optimum range evaluated by Ringbom’s plot method is 10–40 μg mL−1 with an excellent linearity and a correlation coefficient of 0.999. The molar absorptivity and Sandell’s sensitivity of the extractive species were found to be 1.64 × 103 dm3 mol−1 cm−1 and 0.0585 μg cm−2 in the presence of pyridine, and 7.4 × 102 dm3 mol−1 cm−1 and 0.78 μg cm−2 in the absence of pyridine, respectively. The composition of nickel(II)-2ˊ,4ˊ-dinitro APTPT-pyridine was established by the slope ratio method, the mole ratio method and Job’s method of continuous variation. It was found that the metal:ligand:synergent (M:L:Sy) ratio is 1:2:2. To assess the precision and accuracy of the developed method, determinations were carried out at n = 5. The relative standard deviation of all measurements does not exceed 0.16%. Excellent selectivity was found towards the Ni(II) ion due to a specific complex formation between the Ni(II) ion and the organic ligand. In the extraction of Ni(II), several affecting factors, including the solution pH, ligand concentration, equilibrium time, initial Ni(II) ion concentration and foreign ions, were investigated and the applicability of the method was checked by the analysis of synthetic mixtures and alloys. The developed method was successfully used for the determination of nickel(II) from waste water effluents from the foundry region and the nickel plating industry (Kolhapur city). The results obtained by the developed method were also confirmed by AAS. We claimed from this study that Ni(II) could be successfully determined by the spectrophotometric method developed in the current work. The present work is obviously much simpler than the conventional method comprising multistep processes.

희생전극을 이용한 무전해 니켈 도금 폐수의 전기분해처리 최적화

The effluent limit of nickel from electroplating wastewater has been strengthened from 5 mg/L to 3 mg/L from 2014. However, currently applied treatment process for nickel plating wastewater is unable to meet the effluent limit, most of the treatment concept conducted by treatment plant is dilution with other metal bearing wastewater. This can cause very significant impact to the environment of nickel contamination. With this connection, the feasibility test has been conducted with the use of electrolysis by using sacrificial electrodes. Experiments were conducted in synthetic and electroless nickel plating wastewater. Optimal condition of current density, pH were derived from the synthetic wastewater. It was found that the removal efficiency of nickel exceeded 94% at the operation condition of at pH 9 and the current density of 1~2 mA/cm. At this conditions, the iron sludge was generated very low amount. However, it was unsuccessful to meet the effluent limit by applying these treatment conditions to the real electroplating wastewater. This can be explained due to the matrix effect of other metals and anions contained real electroplating wastewater. From the result of further study, the optimal conditions for the real wastewater treatment were found out to be at pH 9, current density 6~7 mA/cm, for 5 minutes of operating time. At these conditions, 88% removal of nickel was achieved, which results the residual nickel concentration was below 3 mg/L.

Simultaneous removal of nickel and phosphorus from spent electroless nickel plating wastewater via calcined Mg–Al–CO3 hydroxides

This picture shows the different adsorption mechanisms of CLDHs for electroless nickel plating wastewater with low and high ionic concentrations.

Study of nickel recovery and organic compound reduction from electroless nickel plating wastewater

Study of nickel recovery and organic compound reduction from electroless nickel plating wastewater

Application of Fered-Fenton and chemical precipitation process for the treatment of electroless nickel plating wastewater

Electroless nickel plating wastewaters commonly contain the citrate chelating complex and the coexisting hypophosphite, which is a scavenger of hydroxyl radicals, typically lowers the catalytic efficiency of H2O2 by Fe2+ in Fenton reaction. Hence, in this work, the Fered-Fenton method was adopted to remediate the citrate, and then alkaline precipitation was utilized to remove the freed nickel ions. The chemical oxidation demand (COD) of citric acid could be efficiently reduced by approximately 95% using 1080mM H2O2 (dosed in continual mode) and 20mM ferrous ions at a current density of 190Am−2 ([citric acid]=100mM and [Ni]=100mM). Meanwhile, 99.9% of the nickel that was liberated from the chelation of citric acid was removed by the cathodic deposition and the sequential precipitation. The hypophosphite did not significantly influence the COD or nickel removal efficiency. Finally, those optimal conditions for the successful management of simulated electroless plating wastewater consisted of citric acid and nickel ions coexisting with hypophosphite were then used to demonstrate the treatment of real wastewater (45,000ppm COD and 8000ppm nickel ions). The high COD removal, 93%, from the effluents of the electroless nickel plating process verified that the Fered-Fenton process can be practically applied.

無電解ニッケルめっき老化液処理への還元晶析法の適用 反応挙動に対する種晶比表面積の影響

In this study, Ni2+ removal from electroless nickel plating wastewater (A. co., Ltd.) by reduction crystallization was investigated, to make clear the effect of seeds specific surface area on the Ni2+ removal characteristics. Although the main reaction in this research is the same as the one in electroless nickel plating, the authors have proposed reduction crystallization in which wastewater from electroless nickel plating contacts with suspended nickel powder, to remove and recover Ni2+. The results could be obtained on the relationship between the pH change profile and recovery efficiency in the reaction process, in which nickel powders having various specific surface area were used as seeds. Experimental results were discussed, considering surface conditions of grown nickel and the behavior of produced fines. With a constant 10% NaOH solution feed rate, the pH profile changed in the process of Ni2+ reduction, by changing the specific surface area of seeds, which means that Ni2+ removal efficiency was affected by the specific surface area of seeds. When constant pH7 was maintained, higher removal efficiency (0.99; Ni2+ concentration in the treated water 2.5×10-2g·dm-3) could be obtained, although the specific surface area of Ni seed powder varied. Specific surface of seeds, based on the roughness of seed crystal, was suggested to be an effective factor on the Ni metal coating behavior on the seed surface and also the phenomena of fines production in the process of Ni deposition.