Recovery Of Cadmium Research Articles

A novel method for clean and efficient separation and recovery of silver and cadmium from silver-cadmium alloy

A novel method for clean and efficient separation and recovery of silver and cadmium from silver-cadmium alloy

Continuous recovery of tellurium and cadmium from simulated CdTe leachates using a fixed-bed-column adsorption system

Rare element resource (Te) loss and heavy metal (Cd) pollution, derived from waste photovoltaic CdTe cells, have attracted considerable attention in the cleaner production and environmental protection field. However, there are several technical barriers in conventional adsorption strategies for the continuous recovery Te(Ⅳ) and Cd(Ⅱ) due to single-component recovery, inefficient adsorbent utilization and less automation. Herein, this work presented a fixed-bed-column adsorption system for the continuous adsorption recovery of tellurium and cadmium from a simulated CdTe leachate using functional sludge-based adsorption fillers (LDO/SF and EDTA@LDH/SF) that prepared from water-processing sludge via hydrothermal synthesis, thermal activation and surface modification technologies. Breakthrough curves were analyzed for adsorption columns, considering initial concentration, flow rate, and filler height, with parameters evaluated using the Thomas and BDST models to determine the optimal separation parameters. During the continuous adsorption process, the column adsorption system with the filler layer height of 4 cm and liquid delivery rate of 1 mL/min can be used for continuous separation of more than 1000 mL of a simulated CdTe leachate and exhibits adsorption efficiencies of more than 96% and 82% for Te(Ⅳ) and Cd(Ⅱ), respectively. More importantly, the elution procedure was used to treat the column adsorption system with ion adsorption acceptances of 83% and 90% for Te(Ⅳ) and Cd(Ⅱ), respectively. Meanwhile, the functional sludge-based fillers demonstrated great regeneration and recycling capabilities, thus maximizing the utilization of adsorbents and saving treatment costs. This study has established a robust technical solution for the continuous recovery of tellurium and cadmium from simulated leachates, providing a practical framework for evaluating the efficiency of adsorption filler columns in actual applications.

Cadmium recovery from acid leachates of Tunisian phosphoric acid purification residues.

The management of cadmium-rich sludges, which are pollutant residues from the phosphorus industry, including the valorization of these sludges through the selective recovery of heavy metals, is a promising prospect. However, there is still a need to develop recovery methods that are both optimized for efficiency, cost-effectiveness, and environmentally friendly. This study aims to enhance cadmium extraction from the polymetallic sludge by optimizing the processes of sulfuric acid (SA) leaching and sodiumsulfide precipitation. Key parameters including SA concentration, temperature, solid/liquid ratio, and stirring velocity were optimized to maximize the heavy metals extraction. Over 90% of the Cd and Zn present in the sludge were successfully extracted. Subsequently, investigates the selective precipitation of metal sulfide from acidic leachates (pH < 2), focusing particularly on cadmium. Through the optimization of chemical precipitation parameters (Na2S concentration, temperature, and reaction time), more than 99% of the cadmium was selectively recovered as CdS. The precipitates underwent analysis for mineralogy, chemistry, purity, and particle size. XRD analyses indicated CdS formation in "Greenockite" and "Hawleyite" forms, confirmed by SEM-EDS data, revealing fine powder consisting of micro and nanoparticles (< 0.5 µm) with varied spherical shapes.

Recovery of cadmium, lead, strontium and zinc from jarosite waste by using a combinatory approach of bioleaching and acid leaching

ABSTRACT Metallurgical processes commonly generate substantial volumes of hazardous waste, and the extraction of zinc is no exception, yielding a byproduct known as jarosite. This study aims to establish an environmentally conscious and economically viable method for recuperating residual metals from jarosite waste. Comprehensive morphological and physico-chemical characterisation of jarosite was performed using XRD, FTIR, SEM and EDS. To facilitate the selective biorecovery of cadmium, lead, strontium and zinc, Shewanella putrefaciens was employed. The efficacy of biorecovery was systematically assessed using both solid-state and liquid-state leaching methodologies. The results indicate that liquid-state leaching outperformed solid-state leaching for all four heavy metal ions. Notably, biotreated jarosite demonstrated markedly superior metal recovery (Cd, Pb, Sr and Zn) compared to non-biotreated jarosite. This investigation advocates for a hybrid approach, involving bioleaching followed by acid treatment, as a more efficacious strategy for the sustainable recovery of heavy metals from jarosite-like waste. These findings not only underscore the potential of environment-friendly biorecovery techniques but also offer a promising avenue for enhancing the ecological sustainability of waste management practices within the metallurgical industry.

The Evaluation of Cellulose Acetate Capsules Functionalized for the Removal of Cd(II).

Cellulose acetate is derived from cellulose and has the characteristics of biodegradability and reusability. So, it has been used for the elimination of toxic compounds capable of producing different diseases, such as cadmium, that result from human and industrial activity. For this reason, capsules functionalized with Cyanex 923 were prepared and characterized by FTIR spectroscopy, Energy Dispersive X-ray Spectroscopy (EDX), and SEM. The functionalized capsules were used for removing and recovering Cd(II) by modifying variables such as HCl concentration in the extraction medium and carrier content in the capsules, among others. The extraction of cadmium from battery leachates and the three isotherm models, Langmuir, Freundlich, and Dubinin Radushkevich, were also tested to model the cadmium removal process. The results showed a favorable physical sorption with a good capacity for extraction and the possibility of reusing the capsules for up to seven cycles without a decrease in the percentage of cadmium recovery.

Evaluation of the effects of L-cysteine addition on the bioleaching of zinc and cadmium from sphalerite flotation concentrate

The primary zinc ore in the world is sphalerite, and roasting-leaching-electrowinning (RLE) is the most typical method of processing. This method has different disadvantages, and bioleaching is an alternative and eco-friendly method for sphalerite treatment. The major drawback of bioleaching is its slow kinetics. In this study, an evaluation of the effects of L-cysteine addition on the bioleaching of zinc and cadmium from a concentrate of sphalerite was investigated in the presence of mixed cultures of mesophilic and moderately thermophilic microorganisms. The results showed that L-cysteine addition increased the dissolution rates of zinc and cadmium while reducing them at higher concentrations. The optimal conditions were achieved by using 0.1 g/L of L-cysteine in mesophilic cultures with zinc recovery of 73.92% and cadmium recovery of 81.45%, respectively. Similarly, zinc recovery was 92.54% in thermophilic cultures, while cadmium recovery was 88.66%. Field emission scanning electron microscopy (FE-SEM) and X-ray diffraction (XRD) analyses have detected the formation of jarosite and elemental sulfur on sphalerite surfaces in mesophilic conditions, as well as ammoniojarosite and elemental sulfur in moderately thermophilic conditions. Fourier transform infrared (FTIR) spectroscopy was employed to identify molecular structures and functional groups on the surface of bioleached residues in mesophilic and moderately thermophilic conditions. To assess the environmental risk of residues, a combination of synthetic precipitation leaching procedure (SPLP) and toxicology characteristic leaching procedure (TCLP) methods were used.

In-situ adsorption-conversion recovery of heavy metal cadmium by natural clay mineral for multi-functional photocatalysis

Pollutant purification, waste recycle and efficient utilization of mineral resources are three main subjects in the environmental fields, while it is hard to achieve simultaneously. Here, we developed a sustainable “adsorbent-to-photocatalyst” strategy for recovering Cd2+ into CdS photocatalyst with clay minerals to simultaneously address the above issues. By comparing the adsorption ability of three natural clay minerals, including sepiolite, attapulgite (ATP) and halloysites, ATP is screened out as a cost-effective adsorbent for the removal of heavy metals Cd2+ from waste water, and then serves as a substrate to allow Cd2+ to be converted into CdS nanoparticles in situ on its surface. The as-prepared CdS/ATP composite materials show multi-functional photocatalytic applications, which are effective in removing heavy metals Cr(VI), tetracycline hydrochloride and killing harmful pathogens in water under visible light. It is demonstrated that the excellent adsorption capacity and production of large number of active species (electrons, holes, hydroxyl radicals and superoxide radicals) are the main reasons for the efficient catalytic activity of CdS/ATP. This study provides a novel reference for the development direction of highly efficient integrated design strategy of heavy metals recovery and high-performance photocatalyst fabrication with cost-effective natural clay minerals.

Preconcentration of Zinc, Cadmium, and Mercury(II) Ions on a Polymeric Modified Adsorbent Based on a Highly Basic ARA-8p Anionite and a Rhodanine Derivative

We studied the conditions for the adsorption of zinc, cadmium, and mercury(II) ions on a modified adsorbent based on an ARA-8p highly basic anion exchange resin and a Rhodanine derivative, 5-(4-carboxyphenyl-azo)rhodanine (ARA-8p-p-KBAR), in a batch mode. The values of pH, phase contact time, and adsorbate concentration at which the maximum recovery of zinc, cadmium, and mercury(II) ions was achieved were determined. The adsorption capacity of the adsorbent for the adsorbed ions was determined from the obtained adsorption isotherms. The calculated value of the free energy shows that adsorption proceeds with the formation of an ionic bond. Eluents were selected to ensure the quantitative desorption of zinc, cadmium, and mercury(II) ions. The interfering effect of macrocomponents and trace elements of water was studied; zinc, cadmium, and mercury(II) ions were quantitatively adsorbed by this adsorbent from a solution of a complex composition. A procedure was developed for the adsorption–atomic-absorption determination of zinc, cadmium, and mercury(II) ions in various water samples.

High-Value Recovery of the Iron via Solvent Extraction from Waste Nickel-Cadmium Battery Sulfuric Acid Leachate Using Saponified D2EHPA

A significant amount of iron from the waste nickel-cadmium (Ni-Cd) battery sulfuric acid leachate seriously hinders the separation and recovery of nickel and cadmium. Therefore, an efficient and economical way to remove iron from this leachate is desired. This paper demonstrated the efficient iron extraction from a simulated Ni-Cd battery sulfuric acid leachate with saponified Di (2-ethylhexyl) phosphoric acid (D2EHPA). The iron-loaded D2EHPA was then stripped with oxalic acid and the iron was recovered in the form of iron oxalate. This process realizes the efficient separation and high-value recovery of iron. The results showed that the saponification of the D2EHPA greatly promoted the extraction of iron from the Ni-Cd battery sulfuric acid leachate. Under suitable conditions, the iron’s single-stage extraction rate was more than 95%, and the iron’s single-stage stripping rate was more than 85%. Moreover, the iron’s extraction rate was more than 99% after two theoretical extraction stages, and the stripping rate was 95.6% after two theoretical stripping stages. The slope analysis determines that five molecules of D2EHPA were combined with one molecule of Fe3+ in the extraction process. The FT-IR analysis shows that the extraction mechanism of Fe3+ using the saponified D2EHPA is a cation exchange. These results can help guide the industrial separation and recovery of iron from the waste Ni-Cd battery sulfuric acid leachate.

The selective and sustainable separation of Cd(II) using C6MImT/[C6MIm]PF6 extractant

Cadmium has been classified as a kind of human carcinogens, and has a strong mobility in the water environment and this can result in serious harm to human health and environmental safety. Here, a new selective and efficient extraction-recovery strategy for Cd purification is provided by using C6MimT/[C6Mim]PF6 as the green extractant. Due to the high compatibility between C6MimT and [C6Mim]PF6, C6MimT-Cd was efficiently separated from the aqueous phase. When the concentration of Cd(II) was 1000 mg/L, the extraction rate could reached 99.9 %. By comparing [C6MIm]BF4 with [C6MIm]PF6, the hydrophobicity restrained the ion exchange between cation and Cd and significantly reduced the loss of extractant. The extracted Cd(II) was separated in the form of precipitation after stripping. The extraction system of C6MimT/[C6Mim]PF6 was stable after several extraction-stripping cycles. The extraction of Cd(II) by C6MimT/[C6Mim]PF6 system mainly realized by forming a neutral and extractable cadmium complexes between Cd(II) and thione. Based on the natural complexation mechanism between metal and C6MImT, Cd exists as obvious competitive advantage in coordination with C6MimT compare to Pb, Zn, Mg, Cr, Fe. This work overcomes the problems of extractant loss and organic pollution caused by volatile or ion exchange, which can only reduce environmental hazards, but also promote the recovery of cadmium and other valuable resources.

Dry biorefinery conversion of cadmium-contaminated rice grain and straw to ethanol with complete collection and recycling of cadmium

Cadmium contaminated rice should be carefully treated by considering two aspects: full recovery of cadmium without risks of emission to environment, and energy balance between input and consumption. Separate treatment of rice grain and rice straw not only generates cadmium contained wastewater but also produces solid residue with livestock feed potentials. This study investigated a dry biorefining treatment to convert whole rice biomass (both grain and straw) into bioethanol at a reasonable energy balance and without solids residue potentials. The cadmium contained wastewater was significantly reduced and further completely evaporated into cadmium-free steam for recycled use in the treatment. The cadmium contained lignin solids were completely burned to evaporate the wastewater. The final cadmium content in combustion ash was enriched by 5–7 folds compared to raw rice biomass. The simulation showed that the heat generation from lignin residue combustion compensated for the energy requirement of wastewater evaporation. This study provides a fully converged treatment method of cadmium contaminated rice biomass on both cadmium and energy consumption with value added bioethanol production.

Water-assisted-mechanical activation of copper pyrometallurgical tailings for molybdenum leaching and selective removal of environmentally-hazardous elements

Fayalite-rich and elemental crystalline blockade of copper pyrometallurgical slag flotation tailings (CSFT) make it difficult to dispose of safely and limits high-value reutilization. Water-assisted milling, a waste-free method, is exploratively employed for activation of CSFT and to improve elemental leachability. In comparison to traditional milling, water-assisted milling reduces the time required for amorphous transition and amorphous nano-mesoporous materials were obtained in 4 h-activated CSFT (SBET increased to 12.25 m2·g−1 from 0.99 m2·g−1; pore size: 2–50 nm). Formation and re-removal of strongly-bound water promoted the hydration expansion of mineral particles and generation of tetrahedral or octahedral silicon defects and vacancies, which provided a large number of active sites and effectively promoted the rapid diffusion and transfer of ions. Water-assisted milling improves the leachability of high-value-added Mo (from 53.09 to > 95 %). During the water-assisted milling process, the dissociation and REDOX reaction of Mo were accelerated by the co-effect of reactive metals (Ca and Al) and the electron migration in the friction environment. This procedure exposed and morphologically changed Mo, facilitated the separation of the iron phase from Mo, and enhanced its solubility in diluted H2SO4 agents. The separation and leaching recovery of high-toxicity arsenic (As) and cadmium (Cd) was enhanced and a preliminary process was proposed for selective leaching of As (>96.99 %) and Cd (96.15 %) by NaOH solution.

Hybrid carbonaceous adsorbents based on clay and cellulose for cadmium recovery from aqueous solution.

The current work describes the synthesis of carbonaceous composites via pyrolysis, based on CMF, extracted from Alfa fibers, and Moroccan clay ghassoul (Gh), for potential use in heavy metal removal from wastewater. Following synthesis, the carbonaceous ghassoul (ca-Gh) material was characterized using X-ray fluorescence (XRF), Scanning Electron Microscopy coupled with Energy Dispersive X-ray (SEM-EDX), zeta-potential and Brunauer-Emmett-Teller (BET). The material was then used as an adsorbent for the removal of cadmium (Cd2+) from aqueous solutions. Studies were conducted into the effect of adsorbent dosage, kinetic time, initial concentration of Cd2+, temperature and also pH effect. Thermodynamic and kinetic tests demonstrated that the adsorption equilibrium was attained within 60 min allowing the determination of the adsorption capacity of the studied materials. The investigation of the adsorption kinetics also reveals that all the data could be fit by the pseudo-second-order model. The Langmuir isotherm model might fully describe the adsorption isotherms. The experimental maximum adsorption capacity was found to be 20.6 mg g-1 and 261.9 mg g-1 for Gh and ca-Gh, respectively. The thermodynamic parameters show that the adsorption of Cd2+ onto the investigated material is spontaneous and endothermic.

Removal of toxic cadmium (II) from zinc sulfate solution with zinc powder enhanced by ultrasound: Kinetics and mechanism

Currently, removing cadmium (II) from zinc sulfate electrolytes using zinc powder presents several problems, such as the agglomeration and encapsulation of the zinc powder, which leads to increased consumption of the zinc powder and poor removal performance. To overcome this limitation, ultrasound is used to assist the replacement of the zinc powder to remove cadmium (II) from zinc sulfate electrolytes. Compared with conventional replacements, the ultrasonic-assisted replacements reduce the reaction time from 120 to 40 min, the reaction temperature from 60 to 55 ℃, and the required amount of zinc powder from 5 to 3 g/L. Under the same process conditions, the replacement rate of cadmium (II) is increased from 68.9 to 98.7 %. According to kinetic studies, ultrasound reduces the required activation energy for replacement from 34.77 to 16.83 kJ/mol, which significantly reduces the energy barrier of the cadmium precipitation. In addition, ultrasound can remove the reaction layer between the zinc powder and cadmium (II), thus accelerating the chemical reaction rate. The kinetic behavior changes when the initial cadmium (II) concentration is in the range of 800–1200 mg/L in conventional experiments, and 1600–2000 mg/L in ultrasound experiments. The characterization of the purification slags confirms that ultrasound can refine particles, improve the replacement rate of cadmium (II), and significantly reduce the consumption of the zinc powder. The ultrasound-enhanced purifying technology of zinc sulfate electrolytes with zinc powder is of great significance for zinc electrowinning and comprehensive recovery of cadmium.

Green synthesis of silicon dioxide nanoparticles and L arginine@silicon dioxide nano- composites using cellulose of Zizyphus Spina-Christi along with biological evaluation

ABSTRACT. The recent research focused on the green synthesis of silicon dioxide nanoparticles, SiO2@Cellulose of Zizyphus Spina-Christi nanocomposites, and L-Arginine@SiO2@Cellulose of Zizyphus Spina-Christi nanocomposites using cellulose of Zizyphus Spina-Christi as a new green polymeric surfactant. The structures of nanoparticles and nanocomposites were characterized by different spectroscopy and microscopy techniques. Nanoparticles and nanocomposites were utilized to determine the concentration of chromium, cadmium, and lead in COVID-19 patients using double-vortex-ultrasonic assisted surfactant enhanced dispersive liquid-liquid microextraction. Mean recoveries of chromium, cadmium, and lead were obtained in the range of 86-98% with relative standard deviations below 4%. The advantages of the proposed method are green and novel polymer surfactant with low detection limit. Finally, antibacterial activities were investigated. The maximum inhibition zone of L-Arginine@SiO2@Cellulose of Zizyphus Spina-Christi nanocomposites was obtained for Staphylococcus Aureus (21.9±0.4 mm). L-Arginine@SiO2@Cellulose of Zizyphus Spina-Christi nanocomposites have low cytotoxicity against MCF-7 cancer cells. These results indicated the potential ability of L-Arginine@SiO2@Cellulose of Zizyphus Spina-Christi nanocomposites in the determination of metal concentrations in biological samples along with good antibacterial properties and cytotoxic properties.&#x0D; &#x0D; KEY WORDS: Green synthesis, Cellulose of Zizyphus Spina-Christi, Silicon dioxide nanoparticles, COVID-19, Biological activity&#x0D; &#x0D; Bull. Chem. Soc. Ethiop. 2023, 37(2), 265-276. &#x0D; DOI: https://dx.doi.org/10.4314/bcse.v37i2.2

Enhanced removal of cadmium from wastewater by electro-assisted cementation process: A peculiar Cd reduction on Zn anode

Cadmium recovery from wastewater is important to prevent water pollution and add value to the circular economy. Cementation is a widely applied method for Cd removal but this process is found less efficient. Herein, a novel electro-assisted cementation process is proposed, which enables effective Cd removal and recovery from Zn processing wastewater. Under optimal conditions, 98.5 % of dissolved Cd was removed and recovered having 94.1 % purity. More importantly, a peculiar Cd reduction on the Zn anode was observed and the mechanism is explained based on the electrochemical test and experimental results. By applying a cell potential of 0.5 V, the negative surface potential of Zn and its localized dissolution facilitated Cd deposition on the Zn anode by suppressing H2 generation. Moreover, in contrast to the conventional cementation process, the formation of Cd dendritic structures on the Zn anode avoided full surface coverage, thus resulting in high cementation efficiency. In summary, this process presents great potential for the efficient removal of Cd from wastewaters and the findings offer new insights into the enhancement mechanism of electro-assisted cementation.

Enrichment of lead and cadmium from water using [formula omitted] nanoparticles/alginate beads: Optimization and determination of significant factors and interaction using response surface methodologies

The optimization, determination of significant factors and interactions between factors of the solid phase extraction method for the enrichment of lead and cadmium in water using P−ZrO2CeO2ZnO nanoparticles/alginate beads was evaluated using Half factorial and Taguchi designs as response surface methodologies in this study. Methods. The beads were characterized using Fourier Transform Infra-Red spectroscopy, Brunauer-Emmet-Teller analysis, Scanning Electron Microscopy and Powder X-ray Diffraction. The amount of adsorbent (50, 100, 150 mg), sample volume (10, 50, 100 mL), eluent volume (10 mL), sample pH (3, 6, 9), eluent concentration (0.5, 1.0 and 2.0 M) and sample flow rate 2 rpm and eluent flow 3 rpm were used during the optimization experiments. The Half factorial design was used to screen for the most significant variables and the Taguchi design was then used to optimize the screened significant variables. Findings The sample volume was the most significant variable for cadmium recovery at p = 0.05. Interactions were noted between sample volume and sorbent dosage, sample volume and pH as well as sorbent dosage and pH. The method was validated by spiking cadmium and lead into borehole and well water samples. The recoveries for metal ions ranged from 57.0 -147.70% for cadmium and 33.12–116.5% forlead, limits of detection were 0.0297 ng/L for cadmium and 0.1022 ng/L for lead. This method exhibits potential for the enrichment of lead and cadmium from water samples.

Selective Recovery of Cadmium, Cobalt, and Nickel from Spent Ni–Cd Batteries Using Adogen® 464 and Mesoporous Silica Derivatives

Spent Ni–Cd batteries are now considered an important source for many valuable metals. The recovery of cadmium, cobalt, and nickel from spent Ni–Cd Batteries has been performed in this study. The optimum leaching process was achieved using 20% H2SO4, solid/liquid (S/L) 1/5 at 80 °C for 6 h. The leaching efficiency of Fe, Cd, and Co was nearly 100%, whereas the leaching efficiency of Ni was 95%. The recovery of the concerned elements was attained using successive different separation techniques. Cd(II) ions were extracted by a solvent, namely, Adogen® 464, and precipitated as CdS with 0.5% Na2S solution at pH of 1.25 and room temperature. The extraction process corresponded to pseudo-2nd-order. The prepared PTU-MS silica was applied for adsorption of Co(II) ions from aqueous solution, while the desorption process was performed using 0.3 M H2SO4. Cobalt was precipitated at pH 9.0 as Co(OH)2 using NH4OH. The kinetic and thermodynamic parameters were also investigated. Nickel was directly precipitated at pH 8.25 using a 10% NaOH solution at ambient temperature. FTIR, SEM, and EDX confirm the structure of the products.

Magnetic solid-phase extraction based on the Carbonized cotton fabric/zeolite imidazolate framework-71/Fe3O4/polythionine followed by atomic absorption spectrometry for cadmium monitoring in water, tomato and cabbage samples

Carbonized cotton fabric/zeolite imidazolate framework-71/Fe3O4/polythionine (CCF/ZIF-71/Fe3O4/PTh) was fabricated, characterized, and applied as efficient magnetic sorbent in magnetic solid-phase extraction (MSPE) of cadmium from water and food samples before determination by flame atomic absorption spectrometry (FAAS). This modification of carbonized cotton fabric led to making a great surface area and porosity, increase extraction efficiency, and acceptable selectivity. The characterization of this proposed sorbent was performed by X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), and Fourier transform-infrared (FT-IR) spectroscopy analysis techniques. The impact of several analytical parameters including pH, sorbent dosage, time of extraction, desorption condition, chelating agent concentration, the amount of salt and effect of potentially interfering ions on the selectivity and extraction recoveries of cadmium, were evaluated and optimized. In this proposed methodology, the limit of detection (LOD), the limit of quantification (LOQ), and relative standard deviation (RSD, n = 3) were found to be 0.21 ng mL−1, 0.6 ng mL−1 and lower than 3.0%, respectively. The validation and accuracy of the new advanced procedure were confirmed by applying the proposed procedure for certified reference materials (SRM1570A). Eventually, CCF/ZIF-71/Fe3O4/PTh can be utilized as a selective sorbent, for the rapid, accurate and sensitive determination of Cd (II) in the samples.

Evaluation of a Causative Species of Harmful Algal Blooming, Prorocentrum triestinum, as a Sustainable Source of Biosorption on Cadmium

Biosorption is an effective method for removing heavy metal ions from wastewater. In the current study, the biosorption capacity of a microalgae Prorocentrum triestinum strain AD1 was investigated for cadmium removal. The efficient biomass concentration was found to be 5 g/L. Based on the Langmuir adsorption model, the maximum adsorption capacity (qmax) value of cadmium removal was found to be 0.0196 mmol/g. The investigation results of the AD1 biosorption kinetics showed that the effective contact time on biosorption was 3 h, and the adsorption kinetics fitted well with the pseudo-second-order model. The optimum pH of biosorption was found to be 5. On the other hand, HCl could act as an efficient desorbent for cadmium recovery from AD1, with an optimum concentration of 0.01 M. These results suggest that the biomass of P. triestinum has great potential for the removal of cadmium from wastewater as an efficient biosorbent.