Electroplating Industry Wastewater Research Articles

Sorption capacity of Eichhornia crassipes (Mart.) Solms for zinc removal from electroplating industry wastewater.

Various industrial operations in the dye, fertilizer, pesticide, battery, mining, and chemical industries have been associated with releasing heavy metals in wastewater, such as lead, zinc, copper, arsenic, cadmium, chromium, nickel, and mercury. These metals are dangerous to aquatic life as well as to humans, who may consume them directly or indirectly. Therefore, before being released into open water and land resources, it is necessary to minimize the concentration of toxic ions below the discharge limit. This study used Eichhornia crassipes (Mart.) Solms to remove zinc from wastewater from the electroplating industry in a constructed wetland. Experimental investigations were conducted for removing zinc ions from electroplating industry wastewater using various process parameters such as nutrient dosages, dilution ratios, potential of hydrogen ions, biomasses, and contact times. The outcome of this study revealed that the maximum zinc removal percentage in electroplating industrial wastewater was found for the optimum nutrient dosages of 60g, dilution ratios of 10, potential hydrogen ion levels of 8, and biomass amounts of 100g. The maximum zinc removal by Eichhornia crassipes (Mart.) Solms was found to be 88.3 ± 0.6 and 93.4 ± 0.4% at the optimum parameter values for the electroplating industry wastewater and the aqueous solution, respectively, against the optimum contact time of 22days. This study suggests using this phytoremediation technology to remove all pollutants from industrial wastewater in general, not just wastewater from the electroplating industry.

Trapping of heavy metal ions from electroplating wastewater with phosphorylated double-shelled hollow spheres

The mesoporous multi-shelled hollow structures are promising for trapping of non-degradable heavy metal ions in wastewater but difficult to synthesize. We successfully demonstrated a simple strategy for the construction of mesopore windows on double-shelled α-Fe2O3 hollow spheres. A step-by-step proof of concept synthesis mechanism has been revealed by using mainly electron microscopy and thermogravimetric analysis. We proved that mesopore windows are indispensable to realize the complete surface coverage of phosphonate ligands on α-Fe2O3 double-shelled hollow spheres. The phosphonic groups inherently coordinated with Ni(II) and Cu(II) ions and formed complexes of high stability. Importantly, owing to the structural merits, the phosphorylated double-shelled hollow spheres selectively removes Ni(II) and Cu(II) at wider sample pH range with a high capacity of 380 mg g−1 and 410 mg g−1, respectively. In addition, no significant decrease in the removal efficiency was observed under high salt matrix. For electroplating industry wastewater, the novel structure performs simultaneous Ni(II) and Cu(II) removal, thus producing effluent of stable quality that meets local discharge regulations.

Synthesis, characterization and application of novel green chelating PE-TH resin in the removal of toxic metals from industrial effluents

One of the world's most serious environmental issues is water contamination produced by toxic metal ions from industrial wastewater. Heavy metal contamination has posed a severe threat to human health and the environment due to its toxicity. To investigate this issue, water contaminated by industrial waste must be rectified with paramount importance. The necessity of generating innovative, environmentally safe remedies to ensure the security of human life and environment is recognized by green chemistry. The purpose of the present research is to synthesize the novel plant-based green chelating resin to trap toxic metal ions from industrial wastewater. The Psyllium Epichlorohydrin Tyrosin Hydroxamate (PE-TH) resin is prepared by crosslinking Psyllium with Epichlorochydrin and Tyrosine amino acid. The total ion exchange capacity (Q) obtained for PE-TH resin is 5.780meq/g. The adsorption coefficient ‘Kd' is obtained by employing the batch adsorption method. The PE-TH resin proved to be very efficient in removing predominantly Cu (II) and Ni (II) ions from the electroplating industry wastewater. The pH range of 7-7.5 produced significant elimination of Cu (II) and Ni (II). The PE-TH resin satisfactorily adsorbs Cu (II) and Ni (II) metal ions from electroplating industry effluents. The newly synthesized PE-TH resin is easy to prepare and is eco-friendly, cost-effective and biodegradable green chelating agent to remove toxic metals ions efficiently from industrial effluents.

ELIMINATION OF HEXAVALENT CHROMIUM ION FROMELECTROPLATING INDUSTRIAL WASTEWATER USING LOCALLYAVAILABLE ADSORBENTS

Human made activities such as industrial practices have released large amount of waste waters into the environment, this has led to the existence of various emerging contaminants (which areexisting in the wastewaters) in the environmental parts. In the process of removing them fromdifferent parts of the environment, method of adsorption is used, this method is proved to be mosteconomical and reliable. In this study, sugarcane bagasse and groundnut shell has been used anadsorbents for the removal of Cr (VI) from electroplating industry waste water, this metal ion isknown to be potentially carcinogenic and mutagenic in nature. Batch experiments and Adsorption isotherms tests were carried out to study the adsorption characteristics of chromium. The removal efficiency of Cr (VI) from wastewater has been compared with different sorption parameters with two adsorbents. The effect of adsorbent dose, contact time and pH were analyzed using batch experiments. The isotherm models were studied to check the suitability of the sorption data of ion with sugarcane bagasse and groundnut shell. Column analysis has been done to check the removal efficiency under different bed depth and initial metal concentration. It is found that under optimum conditions, maximum reduction of Cr (VI) was observed to be 70.12% and 91.28% for sugarcane bagasse and groundnut shell respectively. In isotherm studies, Langmuir isothermmodel best fits for sugarcane bagasse sorption data with a value of R2=0.992 and Fruendlich modelts best to the sorption data of Cr (V I) by groundnut shell with value of R2=0.942. In the columnanalysis, the removal efficiency increases with the increase of bed depth whereas removal efficiency decreases with the increase of metal concentration. The study showed that groundnutshell (maximum removal is 91.40%) is more efficient than sugarcane bagasse (maximum removalis 78.13%).

SEM and XRD for removal of heavy metals from industrial wastewater and characterization of chicken eggshell.

Heavy metal toxicity due to industrial wastewater has been a threat to the environment for the past many decades, especially in developing countries. Electroplating Industry wastewater containing heavy metals can become a serious environmental pollutant if not treated appropriately. Present study investigated the removal of nickel and chromium ions from electroplating wastewater using calcined hen eggshells because of it high removal capability, little cost and easy approachability. Characterization of the adsorbent such as proximate analysis, surface charge, X-ray diffraction, and surface area was done prior to adsorption process. Batch adsorption experiment was performed to study the effect of different parameters such as adsorbent dose, contact time, temperature, and pH for adsorbent. Removal percentage of both heavy metals was checked by using calcined eggshell as adsorbent. Comparison was made between nickel and chromium to identify the most effective removal efficacy. It was concluded that utilization of natural waste was found suitable, easier, cost operative and environmental approachable for removal of heavy metals from industrial wastewater. RESEARCH HIGHLIGHTS: To use ecofriendly approach for the treatment of industrial wastewater. To used calcined eggshell as adsorbents for removing metal concentration from industrial wastewater. To find the metal removal potential of calcined eggshell under various environmental conditions like dosage, contact time, temperature, and pH. To checking the efficacy of calcined eggshell.

Effectiveness of Adsorbents Chicken Eggshells and Cassava Skin to Reduce Pollutants in the Electroplating Industry

The electroplating industry has toxic content that is toxic to living things and the environment. This study aims to examine the values of Cu and Cr levels in the electroplating industry based on variations in adsorbent weight comparison. Adsorbents used are chicken eggshell and cassava skin with a contact time of 90 minutes. Adsorbent comparison used is 20:10, 25:10, and 30:10. After processing by applying the adsorbent system in the electroplating industry wastewater obtained the results of research it appears that the comparison of the weight of adsorbents influenced the decline of Cu and Cr metals with a decrease in Cu by 0.003 mg/l or with the efficiency of 99.43% and a decrease in Cr by 0.962 mg/l or with an efficiency of 95.44%.

Palm kernel fatty acid distillate-based bulk liquid membrane for Cu(II) separation: Design and its operating parameters

This study focus on the development of palm kernel fatty acid distillate (PKFAD) based on a bulk liquid membrane (BLM) as a green membrane for the separation of Cu(II) from wastewater. PKFAD was used as a sole membrane solution without the addition of extractant and/or modifier, which reduced the consumption of hazardous chemicals and favoured the environment. The effects of design (number of stirrer blades and baffles) and operating (stirring speed, buffer solution concentration, and operating time) parameters on the simultaneous extraction and stripping of Cu(II) across PKFAD-based BLM, as well as its overall recovery were investigated to get optimal metal ions recovery. To examine the practical applicability, the selectivity of PKFAD-based BLM in separating Cu(II) was tested using electroplating industry wastewater. The results showed high percentages of extraction (93%), stripping (94%), recovery (87%), and enrichment factor (1.74) of Cu(II) using the best design (four stirrer blades and no baffles) and operating (stirring speed of 220 rpm, buffer solution concentration of 0.2 M, and operating time of 7 h) parameters of PKFAD-based BLM. The separation factor values of ≥1 for Cu(II) over the coexisting metal ions from actual electroplating wastewater have been accomplished with PKFAD-based BLM. Hence, PKFAD-based BLM is a potential BLM with a sole green membrane phase for separating Cu(II) selectively from wastewater.

Treatment of electroplating industry wastewater: a review on the various techniques.

Water pollution by recalcitrant compounds is an increasingly important problem due to the continuous introduction of new chemicals into the environment. Choosing appropriate measures and developing successful strategies for eliminating hazardous wastewater contaminants from industrial processes is currently a primary goal. Electroplating industry wastewater involves highly toxic cyanide (CN), heavy metal ions, oils and greases, organic solvents, and the complicated composition of effluents and may also contain biological oxygen demand (BOD), chemical oxygen demand (COD), SS, DS, TS, and turbidity. The availability of these metal ions in electroplating industry wastewater makes the water so toxic and corrosive. Because these heavy metals are harmful to living things, they must be removed to prevent them from being absorbed by plants, animals, and humans. As a result, exposure to electroplating wastewater can induce necrosis and nephritis in humans and lung cancer, digestive system cancer, anemia, hepatitis, and maxillary sinus cancer with prolonged exposure. For the safe discharge of electroplating industry effluents, appropriate wastewater treatment has to be provided. This article examines and assesses new approaches such as coagulation and flocculation, chemical precipitation, ion exchange, membrane filtration, adsorption, electrochemical treatment, and advanced oxidation process (AOP) for treating the electroplating industry wastewater. On the other hand, these physicochemical approaches have significant drawbacks, including a high initial investment and operating cost due to costly chemical reagents, the production of metal complexes sludge that needs additional treatment, and a long recovery process. At the same time, advanced techniques such as electrochemical treatment can remove various kinds of organic and inorganic contaminants such as BOD, COD, and heavy metals. The electrochemical treatment process has several advantages over traditional technologies, including complete removal of persistent organic pollutants, environmental friendliness, ease of integration with other conventional technologies, less sludge production, high separation, and shorter residence time. The effectiveness of the electrochemical treatment process depends on various parameters, including pH, electrode material, operation time, electrode gap, and current density. This review mainly emphasizes the removal of heavy metals and another pollutant such as CN from electroplating discharge. This paper will be helpful in the selection of efficient techniques for treatment based on the quantity and characteristics of the effluent produced.

Electroplating wastewater treatment

This paper considers the applicability of complex titanium coagulants in the treatment of electroplating industry wastewater. Complex titanium coagulants were found to significantly outperform the conventional coagulants containing aluminium or iron compounds in terms of decreasing the concentration of suspended matter (insoluble forms of metals). The average effective dose of complex titanium reagents was 1.5 to 2.0 times lower than that of conventional reagents. Complex titanium reagents proved to be more efficient for removing copper compounds from wastewater after copper plating with complex ammoniumtartrate electrolytes. When compared with aluminium salts, the residual concentration of copper ions and the effective dose of titanium reagents were significantly lower. Due to forming easily soluble complexes with organic ligands and due to hydrolysis inhibition, iron salts did not prove efficient. The authors proved that the use of complex titanium coagulants helps intensify (by more than 20%) sedimentation and filtration of coagulation slurries. This, in turn, will help to significantly raise the efficiency of wastewater treatment facilities and make them more compact. Combined with low consumption of reagents, this can help make wastewater treatment processes a lot more cost-effective. The research data obtained suggest that complex titanium reagents can be efficiently used for treatment of acid-base and copper-bearing wastewater generated by the electroplating industry.

Processing of electroplating industry wastewater through dual chambered microbial fuel cells (MFC) for simultaneous treatment of wastewater and green fuel production

Microbial fuel cells (MFC) provide a breakthrough development for wastewater treatment combined with electricity production. Though, MFC applications are restricted in laboratory scale level. Present study an effort has been made to employ the electroplating industrial wastewater as feedstock in dual chambered anaerobic microbial fuel cell for organic content removal as well as energy production. The ultimate goal of this research is to analyze the effect of organic load (OL) on removal of organic matter and power production. The maximum removal efficiency of total, soluble oxygen demands (TCOD, SCOD) and total suspended solids (TSS) of about 87%, 79% and 72% respectively was obtained at the OL of 1.5 gCOD/L. The maximum power and current density of about 260 mW/m2 (6.2 W/m3) and 364 mA/m2 was also recorded at a same OL of 1.5 gCOD/L. From the above findings proposed that utilization of high strength organic wastewater in MFC could pave the way to handle the problem of electroplating industries as well as minimize a small portion of energy demand.

Quaternary amine synthesized ionic polymer for efficient removal of Cr(VI) in waste water

A series of imidazolium-based ionic polymer (ImIP2Br, ImIP3Br and ImIP4Br) were successfully prepared by quaternization reaction of 1,4-dimethyl bromide benzene, 1,3,5-tri(bromomethyl), 1,2,4,5-tetramethyl and 1,3,5-tri(1H-imidazol-1-yl)benzene. The as-prepared ImIP2Br, ImIP3Br and ImIP4Br ionic polymers were characterized by SEM, STEM, FTIR, TG and solid-state 13C NMR measurement. In the aqueous solution of [imidazolium] to [Cr] 1:1, the removal rate of Cr(VI) by ImIP4Br was 98.4%, which was much higher than that of ImIP2Br, ImIP3Br. In addition, the ImIP4Br was applied for efficient removal of Cr(VI) for extremely low concentration of Cr(VI) solution and electroplating industry wastewater by anion exchange. Finally, a series of experimentals studies were performed to study the enrichment of hexavalent chromium and evaluate the recycling and reproducibility of ImIP4Br. The result showed the concentration of the residual Cr(VI) is only 0.09 mg L−1, which is lower than the permissible limit of Cr(VI) discharge (0.10 mg L−1) according to the regulations of the US Environmental Protection Agency. For the actual electroplating wastewater, the adsorption efficiency of ImIP4Br for Cr(VI) is over 99.8%, despite the competitive adsorption of other ions in the solution. In a word, ImIP4Br shows outstanding enrichment ability, good regenerative ability and superior recyclability for removal of Cr(VI). The combination of promising removal performances endows ImIP4Br with great promises for capture and separation of Cr(VI) from contaminated water systems.

Investigation on the removal of bivalent cadmium ions from aqueous solution and treatment of industrial wastewater using new alumina interfaced biocarbon

The presence of heavy metals in water and wastewater is becoming a severe environmental and public health concern. It may contribute variety of adverse environmental and human health effects due to their acute and chronic exposure through air, water and food chain. They are released into the aquatic environment from many industrial activities. The present research paper deals with the adsorption capacity of the biocarbon material produced from the leaves of Lawsonia inermis plant. The biocarbon was prepared by the H2SO4 activation process. The adsorption capacity of the biocarbon was evaluated by considering the effect of various parameters such as pH of the solution, biocarbon dose, contact time, and initial metal ions concentration and to optimize the conditions for maximum adsorption. The metal ion uptake capacity of the biocarbon was tested in the stimulated wastewater containing bivalent cadmium ions. The maximum uptake of 97.85% of the Cd (II) metal ions was observed at the equilibrium time of 3.0 hours at a dose of 3.0 g and at the pH of 4.5 in the stimulated wastewater. In the real sample analysis, electroplating industry wastewater is used for the removal of cadmium (II) ions. The results indicate that 95.16% of ions were effectively removed at the same experimental conditions. It is also further noted that the metal sorption capability of the adsorbent is higher with rising concentration of metal ions in the solution. The percentage of adsorption of the metal ions was also significantly increased with rise of temperature of the wastewater.

Review on the treatment of electroplating industry wastewater by electrochemical methods

Fate and health exposure linked with pollutants in water are one of the major environmental protests. Electroplating wastewater involves toxic pollutants, which are harmful to living organisms. During the last two decades, advanced oxidation processes (AOP’s) for effectively decontaminate water have drawn great attention. Among various AOP’s, electrochemical technologies appear to be the most promising methods for removing organic pollutants from industrial wastewater. The main objective of this review is to study the feasibility of electrochemical methods for the treatment of electroplating effluents and also found that the rate of toxic pollutants removal was significantly influenced by different anode materials.

Removal of Zinc and Chromium from industrial wastewater using water hyacinth (E. crassipes) petiole, leaves and root powder: Equilibrium study

Abstract Water hyacinth (Eichhornia crassipes) is known for its rapid invasive growth on surface of water bodies which inturn cause many ill-effects on biodiversity. The current study was performed on the remediation of Zinc and Chromium metal ions from Electroplating Industry Wastewater (EIW) using dried biomass of aquatic macrophyte – water hyacinth. The potential of powdered parts of (leaves, petiole, root) water hyacinth was studied through influential parameters such as biosorbent dosage, initial concentration of heavy metals, initial pH and contact time. Batch adsorption studies were conducted followed by column studies. Biosorbent prepared from root showed maximum Zinc (Zn) removal of 98.9% and stem showed Chromium (Cr) removal of 96.4% respectively. The obtained data was fit into equilibrium studies ie. Freundlich and Langmuir isotherms. Equilibrium studies confirmed the conformity of the adsorption isotherms to Langmuir and Freundlich isotherms for the stem sample in removal of Chromium and the root sample was found to conform to the Langmuir isotherm in removal of Zinc.

Copper removal kinetic from electroplating industry wastewater using pulsed electrodeposition technique

ABSTRACT This study presents a kinetic determination of copper removal from a real jewelry industry wastewater, with removal reaching 82.49% at 37°C, using fast galvanic pulse electrochemical technique in a process lasting 115 min. In the temperature range from 20 to 40°C, the mathematical model of the pseudo-first-order irreversible rate equation, with a correlation coefficient of 0.99, described the process behaviour. In this same temperature range, the Arrhenius’ equation described the system, in which the temperature increase favoured the reaction kinetics. The scanning electron microscope (SEM), with energy-dispersive X-ray detector (EDX), X-ray photoelectron spectroscopy (XPS) results, and the mathematical model fitting at the temperatures of 10 and 50°C indicated the formation of copper oxide I.

Autonomous pH control by reinforcement learning for electroplating industry wastewater

The electroplating industry, due to steps such as pickling, generates acid pH wastewater. Its treatment is important for environmental preservation and the future recovery of metals. Therefore, the main objective of this work was the development of an autonomous pH controller for electroplating industry liquid effluents, based on fully automated Reinforcement Learning (RL). In order to do that, a Continuous Stirred-Tank Reactor (CSTR) neutralization simulator, and an adapted Particle Swarm Optimization (PSO) algorithm to automate the choice of RL hyperparameters were developed. The controller was developed and validated when it stabilized the effluent's pH in a neutral range in different scenarios during the regulatory and servo operations better than a Proportional Integral Derivative (PID) controller. The development of autonomous wastewater pH control systems in coated surface treatment units is a significant advancement, as it reduces human intervention and allows the monitoring of variability associated with the electroplating industry.

Anticorrosive Zn–Ni alloys: An alternative for the treatment of electroplating industry wastewater

Substrate protection coatings are widely applied in the industry. Zn–Ni alloys have less potential for corrosion, thus preserving the steel substrate by corroding first. In this sense, this study used nickel-rich electroplating industry wastewater to produce Zn–Ni alloys under different conditions, analyzing the zinc sulfate concentration, electric current density, and rotating cathode in the deposition. The nickel removal kinetics showed a reversible and first-order behavior. The alloys with a composition of 2 wt.% nickel, according to energy-dispersive X-ray spectroscopy analysis, were more anti-corrosive with polarization resistance of 1276.7 Ω cm2, than the alloys containing 5 wt.% nickel. Electrochemical impedance spectroscopy proved that alloys containing 2 wt.% nickel were more resistant to corrosion and indicated the formation of a porous oxide layer. Besides, the micrographs of the alloys containing 2 wt.% nickel showed homogeneity without cracks and nodular grains, unlike the alloys with 5 wt.% nickel, which had cracks and were heterogeneous. The X-ray diffraction diffractograms showed different structures according to the amount of Ni. Thus, the deposition of metals from wastewater is an alternative to conventional treatments and avoids the use of synthetic baths.

An alternative method of removing Cr (VI) from aquatic solution using chemically modified cone biomass and Fomitopsis pinicola

We report the adsorption of Cr (VI) ions from aqueous solution by forest waste. Two adsorbents were prepared from cone biomass and Fomitopsis pinicola. To study the kinetics of both were used three particular size (<0.5, 0.5-1, 1-2 mm). It was found that adsorbents chemically modified with a HCl (activation 2mol/L, activated for 60 min) demonstrated better Cr(VI) removal capabilities as compared to pure adsorbents in terms of their adsorption rate. The optimum conditions for removal of Cr(VI) were found to be particular size <0,5 mm, pH=1, contact time 10 min, adsorbent dosage 20g/L, concentration of Cr(VI) 100 mg/L, temperature 25 ± 1°C, rpm 200. The percent removal at these optimum conditions was found to be 100 % for both biosorbents. The Langmuir model fitted the equilibrium data better than the Freundlich isotherm. The maximum uptake capacities for 40.98 mg/g and 45.05 mg/g for cone biomass and Fomitopsis pinicola, respectively. To study the effect of other ions on the Cr (VI) removal by both biosorbents, electroplating industry wastewater was collected from an industry. Overall, the experimental results suggest that cone biomass and Fomitopsis pinicola could be used as low cost alternative adsorbents for the treatment of low concentration Cr (VI) containing wastewater.

Bioremediation Using Bacillus subtilis and Saccharomyces cerevisiae to Reduce Chromium in Electroplating Liquid Waste

&lt;p&gt;The electroplating industry produces liquid waste containing a small number of heavy metals but is toxic. Wastewater containing chromium (Cr) absorbed into the soil will affect soil fertility. Waste management is needed so that the abiotic and biotic environment is not poisoned by Cr. Bioremediation using bacterial and fungal microbes are applicable to reduce Cr levels in electroplating liquid waste. The purpose of this research was to investigate the reduction level of Cr in electroplating liquid waste through bioremediation using &lt;em&gt;Bacillus subtilis&lt;/em&gt; and &lt;em&gt;Saccharomyces cerevisiae&lt;/em&gt;. Laboratory experiments were conducted using variations in microbial concentrations (10&lt;sup&gt;2.5 &lt;/sup&gt;cells ml&lt;sup&gt;-1&lt;/sup&gt; and 10&lt;sup&gt;5&lt;/sup&gt; cells ml&lt;sup&gt;-1&lt;/sup&gt;), variations in microbial types (&lt;em&gt;Bacillus subtilis&lt;/em&gt; bacteria, &lt;em&gt;Saccharomyces cerevisiae&lt;/em&gt; fungi, and mixtures of both microbes), and variations in incubation time (6, 12, and 24 hours). The initial Cr concentration and the results of the bioremediation process were determined by measuring the absorbance and the Cr levels using Atomic Absorption Spectrophotometry (AAS). Based on experiments, the use of &lt;em&gt;Bacillus subtilis &lt;/em&gt;10&lt;sup&gt;2.5&lt;/sup&gt; cells ml&lt;sup&gt;-1&lt;/sup&gt; with a 24-hour incubation time reach the highest percentage reduction in Cr (88.96%), followed by 12-hours incubation time (84.73%), and 6-hours incubation time (79.21%). Furthermore, the use of a microbial mixture of &lt;em&gt;Bacillus subtilis&lt;/em&gt; and &lt;em&gt;Saccharomyces cerevisiae&lt;/em&gt; 10&lt;sup&gt;2.5&lt;/sup&gt; cells ml&lt;sup&gt;-1&lt;/sup&gt; with 6-hours, 12-hours and 24-hours incubation time was able to reduce the levels of Cr respectively by 77.46%; 80.18% and 83.04%. Next, &lt;em&gt;Saccharomyces cerevisiae&lt;/em&gt; 10&lt;sup&gt;5&lt;/sup&gt; cells ml&lt;sup&gt;-1&lt;/sup&gt; with 6-hours, 12-hours, and 24-hours incubation time was able to reduce levels of Cr in a row by 50.17%; 52.35% and 55.63%. The results of this study indicate that the bioremediation process using the microbial &lt;em&gt;Bacillus subtilis&lt;/em&gt; and &lt;em&gt;Saccharomyces cerevisiae&lt;/em&gt; is proven to reduce the levels of Cr in the electroplating industry wastewater. The highest reduction results were achieved on the use of 24-hour incubation time and the use of &lt;em&gt;Bacillus subtilis&lt;/em&gt; with a concentration of 10&lt;sup&gt;2.5&lt;/sup&gt; cells ml&lt;sup&gt;-1&lt;/sup&gt; at 88.96%.&lt;/p&gt;

New organizational principles of combined treatment of the electroplating industry wastewater

New organizational principles of combined treatment of the electroplating industry wastewater