Removal Of Zinc Research Articles

Simultaneous adsorption of phosphate and zinc by lanthanum modified zeolite

Lanthanum modified zeolite (LMZ) has been proven to be an effective inactivation agent for lake internal phosphorus load control. However, its performance in the co-sequestration of P and heavy metal is still unclear. Thus, simultaneous adsorption of phosphate and zinc by LMZ was investigated in this study, and its co-inactivation performance in sediment was also verified. Separate adsorption capacities of LMZ for phosphate and zinc were 2.31 and 0.367 mmol/g, respectively. In co-adsorption scenario, removal rate of zinc (0.15 mmol/L) increased from 73.53 to 84.60% when co-existing phosphate increased from 0.097 to 0.48 mmol/L (pH 6.5), while zinc had an inapparent impact on phosphate adsorption. Furthermore, an increase of background NaCl concentration in the system inhibited zinc removal by 25%, indicating that part of zinc was physically adsorbed by the zeolite fraction of LMZ. XPS and Raman spectra suggested that phosphate in the simultaneous adsorption system was innerspherically adsorbed by lanthanum oxide component of LMZ, while zinc was adsorbed by forming both outer-sphere complex and inner-sphere complex. Part of zinc could chelate with the adsorbed phosphate, forming phosphate bridged ternary complex and enhancing zinc removal. Finally, a lab-scale inactivation experiment showed that simultaneous stabilization of P and zinc in sediment could be achieved by dosing 5% weight percentage LMZ, making it a promising inactivation agent in the future. • Simultaneous adsorption of phosphate and zinc by lanthanum modified zeolite (LMZ) was investigated. • Zinc adsorption was enhanced by co-existing phosphate, while phosphate adsorption was not influenced by zinc. • LMZ is a promising agent for the simultaneous inactivation of P and zinc in sediment.

Wood ash amended biochar for the removal of lead, copper, zinc and cadmium from aqueous solution

Heavy metals in motorway adjoined aqueous environments have increased at an alarming rate over recent years. This increase has been primarily attributed to anthropogenic activities such as the increase of motor vehicle use. Current remediation techniques, such as balancing ponds have the potential to leave toxic residue with the associated removal costs often proving prohibitive. In this study biochar and wood ash amended biochar were evaluated as remediators of inorganic vehicular pollutants found in motorway runoff, specifically Pb, Cu, Zn and Cd. Biochar from European larch ( Larix decidua (L.) Karst.) was produced via fast pyrolysis-gasification (485–530 °C for 90 s) and amended with wood ash post pyrolysis. Pristine larch biochar (BC), larch biochar cold mixed with wood ash (WA) and larch biochar sintered with wood ash (WAS) were studied to evaluate metal immobilisation mechanisms and maximum removal capacities. This study demonstrates that the amendment of biochar with wood ash increases Pb, Cu, Zn, and Cd immobilisation by an order of magnitude compared to BC. The addition of wood ash increases pH whilst adding minerals causing precipitation. Precipitation and ion exchange dominate metal immobilisation and were not correlated to surface area. Sustainability of feedstock, low feedstock/production costs and maximum measured contaminant removal (61.5 mg/g, 38.9 mg/g, 12.1 mg/g and 10.2 mg/g for Pb, Cu, Zn and Cd respectively) indicate that wood ash amended biochar is a viable option to immobilise Pb, Cu, Zn and Cd from motorway runoff. • The addition of wood ash to biochar increased metal removal by an order of magnitude. • Immobilisation is correlated to pH. • Increased pH and the presence of minerals drive precipitation. • Precipitation and ion exchange dominate immobilisation. • Wood ash amended biochar could remove heavy metals from motorway runoff.

Zinc removal from highly acidic and sulfate-rich wastewater in horizontal sub-surface constructed wetland.

This study demonstrated the successful use of a laboratory-scale baffled horizontal constructed wetland substituted with mixed organic media for zinc removal from high acidity (∼610 mg L-1 as CaCO3), sulfate-rich (∼1,300 mg L-1) wastewater. The wetland was planted with Typha latifolia. The mean zinc concentration in the influent was gradually increased from 0.56 ± 0.02 mg L-1 to 5.3 ± 0.42 mg L-1. The mean zinc concentration in the outflow was 0.22 ± 0.19 mg L-1, which accounted for 95% zinc removal throughout the study. However, total zinc uptake by the plants was 533 mg kg-1, accounting for only 1.2% of total zinc removal; therefore, major zinc retention occurred within wetland media (83%). The overall activity and specific sulfidogenic activity decreased at the end of the study to 1.43 mg chemical oxygen demand removed per mg of TVS per day and 0.60 mg sulfate reduced per mg of TVS per day, respectively. Additionally, 16S rRNA sequencing revealed major dominant phyla present: Firmicutes (36%), Proteobacteria (16%), Actinobacteria (8.8%), Planctomycetes (7.8%), Chloroflexi (3.5%), Acidobacteria (1.9%) and Fibrobacteres (1.5%).

Effect of aqueous extract of Artemisia herba-alba on functional sperm parameters of male rats

Artemisia species have a high economic value in several fields, as food plants and as antihelminthic and antimalarial in medicine Many of the species of Artemisia have found their way into folklore medicine. In Libya commonly referred to as wormwood also called Alshih, the genus Artemisia is represented in Libya by seven species namely A. arborescens L, A. campestris L, A. glutinosa, A. herba-alba, A. judaica, A. monosperma and A. variabilis. This study, for the first time, documented the effects of an aqueous extraction of Artemisia Herba-Alba in the rat investigating male reproductive functions. From the results obtained, it is evident that the herbal extract in the low dose (10mg/kg) had a beneficial effect on all parameters, with the exclusion of sperm morphology. In this regard, active compounds present in the plant might have caused an increased production of serum testosterone which resulted in the enhancement of sperm quality in the rat. Another explanation for the increase in sperm functionality might have been induced by the presence of components within the plant of Artemisia Herba-Alba causing the efficient removal of zinc from spermatozoa enabling them to reach optimal motility. It is also possible that these two explanations given above could have occurred simultaneously, thereby enhancing the positive effects observed within this study. This study indicated that the traditional use of this herbs has effects on male reproductive health.

A GREEN METHOD FOR THE REMOVAL OF ZINC(II) IONS FROM WASTEWATER USING MODIFED BIOPOLYMERS

Zinc pollution in wastewater is a global problem because it is highly toxic. Zinc is commonly used in industries that transfer the water containing zinc directly into water sources, leading to pollution. Exposure to a high level of zinc causes major health problems. This study evaluated the adsorption of zinc ions from aqueous system using modified biopolymers of chitosan by crosslinking with sulphates using the batch adsorption method; the concentration was determined using atomic absorption spectrophotometry. The sulphate cross-linked chitosan (SCC) was characterised by several method. The effects of various experimental parameters such as pH, contact time, concentration, adsorbent dosage and temperature were investigated. Under the optimised conditions, the percentage efficiency for the removal of zinc(II) was up to 85%. Freundlich and Langmuir isotherms were used to analyse the equilibrium adsorption data along with kinetic studies. Various thermodynamic parameters have also been reported.

Separation of zinc and iron from secondary manganese sulfate leachate by solvent extraction

Purification of concentrated manganese sulfate solution by solvent extraction is discussed in this paper. The use of bis(2-ethylhexyl)hydrogen phosphate(D2EHPA) and bis(2,4,4-trimethylpentyl)phosphinic acid (BTMPPA) was studied in removal of impurities from zinc electrowinning anode sludge leachates. Over 99% of zinc and iron were removed by both extractants at around pH3 in two mixer-settlers operating in continuous countercurrent mode at a solvent-to-feed (S/F) ratio of 0.43 and T = 22 ± 1 °C. BTMPPA had higher selectivity for zinc and iron over manganese than D2EHPA under all experimental conditions. Extraction of manganese was typically below 10% and can be limited by crowding the extractants, since the fraction of manganese in both loaded extractants was decreased by decreasing organic to aqueous volumetric ratio (O/A). A significant amount of the co-extracted Mn was recovered by selective stripping with 0.5 M sulfuric acid. Extraction by BTMPPA was more sensitive to pH adjustment than extraction by D2EHPA. Increasing the mean residence time in mixer from 3.6 min to6.0 min improved the removal of zinc and iron with BTMPPA but the change in residence time had little or no effect on zinc and iron removal with D2EHPA.

Central Composite Design for Adsorption of Pb(II) and Zn(II) Metals on PKM-2 Moringa oleifera Leaves.

Biosorption is a very effective technique to eliminate the heavy metals present in the wastewater that utilize nongrowing biomass. The adsorption ability of the Periyakulam-2 (PKM-2) variety of Moringa Oleifera leaves (MOLs) to eliminate Pb(II) and Zn(II) ions from an aqueous solution was examined in this work. Fourier transform infrared (FTIR) spectroscopy, field-emission scanning electron microscopy, energy-dispersive X-ray (EDX) analysis, X-ray powder diffraction, and Brunauer–Emmett–Teller methods were used to characterize the PKM-2 variety of MOLs. The set of variables consists of the metal ion initial concentration, a dosage of the adsorbent, and pH were optimized with the help of the response surface methodology to get maximum metal removal efficiency of lead and zinc metals using the PKM-2 MOL biosorbent. A maximum Pb(II) removal of 95.6% was obtained under the condition of initial concentration of metal ions 38 mg/L, a dosage of the adsorbent 1.5 g, and pH 4.7, and a maximum zinc removal of 89.35% was obtained under the condition of initial concentration of metal ions 70 mg/L, a dosage of the adsorbent 0.6 g, and pH 3.2. The presence of lead and zinc ions on the biosorbent surface and the functional groups involved in the adsorption process were revealed using EDX and FTIR analysis, respectively. The adsorption data were evaluated by employing different isotherm and kinetic models. Among the isotherm models, Langmuir’s isotherm showed that the best fit and maximum adsorption capacities are 51.71 and 38.50 mg/g for lead and zinc, respectively. Kinetic studies showed accordance with the pseudo-second-order model to lead and zinc metal adsorption. Thermodynamic parameters confirmed (ΔG° < 0, ΔH° < 0, and ΔS° > 0) that the sorption mechanism is physisorption, exothermic, spontaneous, and favorable for adsorption. The results from this study show that the MOL of the PKM-2 type is a promising alternative for an ecofriendly, low-cost biosorbent that can effectively remove lead and zinc metals from aqueous solutions.

Mechanism of interaction and removal of zinc with lignocellulosic adsorbents, closing the cycle with a soil conditioner

Batch experiments were performed to remove Zn2+ by adsorption process using organic residuals (pistachio, peanut, and almond) as an adsorbent. The adsorbents were characterized by FTIR spectra, SEM images, and elemental analysis. Optimum adsorption of Zn2+ was obtained at pH 6 with a contact time of 45 min at room temperature with 1.0 g adsorbents. The adsorption of Zn2+ was found to well describe Langmuir isotherm model and a pseudo-second-order rate equation. The maximum adsorption capacity of pistachio, peanut, and almond is as follows; 59.52 mgg-1, 54.64 mgg-1, and 51.81 mgg-1, respectively. Functional groups on shell surfaces can cooperate with metal ions in many ways such as electrostatic interaction, ion exchange, complex formation, and diffusion. This study has shown that pistachio, peanut, and almond shell can be used for reducing Zn2+ from aqueous solutions as an eco-friendly, low-cost adsorbent. The end-product containing organic compounds and zinc can be used as a soil conditioner. Furthermore, the usage of the organic shell as a sorbent for the capturing of zinc from contaminated water ensures both the technical advantage and cost-effectiveness for the sustainable environmental management concept.

Copper and Zinc Removal Efficiency of Two Reactive Filter Media Treating Motorway Runoff—Model for Service Life Estimation

The predominant techniques used for road runoff treatment are sedimentation and filtration. In filtration systems, the ability of the media to adsorb the contaminants is a finite process. Consequently, construction, operation and maintenance managers of such systems should know in advance the service life, i.e., when the used medium should be replaced, and associated costs of operation and maintenance. A batch experiment followed by a packed bed reactor (PBR) experiment addressed the kinetics of the studied media argon oxygen decarburization slag (AOD) and Polonite, followed by the development of a 1D-model to describe the change of concentration of Cu and Zn within time. The batch test results showed that Cu and Zn adsorption followed the Freundlich isotherms for AOD and Polonite. Those results coupled with the linear driving force model and the developed model resulted in good agreement between the PBR results and the simulation. The model was capable to predict (i), the service life at the hydraulic load of 0.18 m/h for AOD (Cu: 395 d; Zn: 479 d) and Polonite (Cu: 445 d; Zn: 910 d), to show (ii) the profile concentration in the PBR within time and the gradient of the concentration along the height of the reactor.

Biological treatment of heavy metals removal from Sewage

A sample of the bread yeast Saccharomyces cerevisiae strain was taken from the local markets in the city of Mosul and grown on the appropriate medium for it in order to test its ability to remove some heavy metals. Concentrations for each metal ph and three temperatures The grown bread yeast was able to remove both zinc and lead alone and remove them both. The highest removal of zinc was 1.99 ppm , and lead was 0.5 ppm. It was noted that the removal rate increased according to the two minerals together, as the temperature was 10 and 25 The best value for pH is 4 and 9

Clay–fly ash geopolymer characterisation and application for the removal of lead and zinc

This research aims to enhance the adsorption capacity of local clay using a fly-ash-based geopolymer representing active–passive liner materials. Clay–fly ash geopolymers were synthesised from mixtures containing 40, 50 and 60% fly ash to the total solid mass and then activated by 8, 10 and 12 M sodium hydroxide (NaOH) solutions. Batch experiments were conducted for the removal of lead (Pb), lead (II), and zinc (Zn), zinc (II), from leachate at an ambient temperature of 24°C after a 90 min contact time. Then, for the clay–fly ash geopolymer exhibiting the best adsorption capacity, the effects of contact time, initial concentration of solutes and curing time on its adsorption capacity were thoroughly studied. The best performance for the adsorption of lead (II) and zinc (II) occurred with the lowest percentage – that is, 60% – of clay in the synthesised geopolymers due to the diminished competitor ion concentration released by the alkali activation of clay. There, moreover, existed a notable correlation between the porosity and adsorption capacity of the adsorbents to develop the eminent adsorption of the heavy metals, particularly for lead (II) removal. The study of Langmuir and Freundlich isotherms also showed that the adsorption of lead (II) is described by homogeneous surfaces, while heterogeneous surfaces characterise zinc (II) removal. This refers to the different adsorption process for the removal of zinc (II).

Removal of zinc, lead and nickel from contaminated soil by electro-kinetic technology under the influence of washing and buoyance forces with different purging solutions

ABSTRACT The effects of the washing process, purging solution, and buoyance force (inclined topography action) on the effectivity of the electro-kinetic method used to remediate of a silty clay loam and natural soils contaminated with Zn, Pb and/or Ni were investigated by applying 12 different experiments. The results revealed that the washing process and buoyance force can cause a small increase in the Zn removal efficiency (≤ 31%) when compared with non-washing approach using distilled water purging solution. Using 0.1 M of EDTA solution for the soil contaminated with listed metals in combination with washing can lead to significant increase in the removal efficiencies with percentages not greater than 58.4, 60.68 or 42.8%, respectively. In the presence of EDTA, however, the majority of metals passed through the soil media to the anode area. In contrast, these metals are accumulated near the cathodic region in the presence of distilled water. The results demonstrated that the buoyance force (resulted from inclination angle of 30°) with EDTA had adverse influence on the metal profile along the treated soil. Finally, the results certified that EDTA in electro-kinetic process coupled with soil washing is a new hybrid technique which achieved Pb removal efficiency from natural soil reached to 58% by improving the solubilization and transport of metal ions.

Removal of Cadmium, Nickel, and Zinc from aqueous solutions by activated carbon prepared from corncob - waste agricultural materials

Adsorption of zinc (Zn), cadmium (Cd), and nickel (Ni) from aqueous solutions by corncob (CC) and granular activated carbon prepared from corncob (GACC) were carried out. Synthetic solutions of Cd, Ni, and Zn at 3.0 ppm each were used to perform the adsorption process. A batch pattern was used to determine the kinetics as well as the adsorption isotherm parameters. The obtained results using either both the CC and GACC separately were found to be matched with the Langmuir isotherm model. Furthermore, the breakthrough study was conducted using GACC. The overall results indicated that the breakthrough curve for Cd, Ni, and Zn is the reverse of their adsorption, as demonstrated by R2 and kinetic constant (K) values.

Simultaneous high-efficiency removal of sulfamethoxazole and zinc (II) from livestock and poultry breeding wastewater by a novel dual-functional bacterium, Bacillus sp. SDB4.

The complex mixtures of antibiotics and heavy metals are commonly existed in livestock and poultry breeding wastewater. Effective and simultaneous removal of these toxic compounds by microorganisms, especially single strains, remains a considerable challenge. In this study, a novel functional strain SDB4, isolated from duck manure and identified as Bacillus sp., has been shown to possess high removal capabilities for both sulfamethoxazole (SMX) and Zn2+. The maximum removal efficiency achieved 73.97% for SMX and 84.06% for Zn2+ within 48 h in the single pollution system. It has great potential for eliminating SMX along with Zn2+, 78.45% of SMX and 52.91% of Zn2+ were removed in the 20 mg·L-1 SMX and 100 mg·L-1 Zn2+ binary system. Furthermore, the SMX-biotransformation capability of SDB4 was enhanced at low concentrations of Zn2+ (below 100 mg·L-1). The SMX biotransformation and Zn2+ adsorption data fitted well with the pseudo-first-order kinetic model, indicating that the two pollutants were in accordance with the same removal rule. N4-acetyl-SMX was identified as the main stable transformation product during SMX removal. FTIR analyses revealed that OH, NH2, C=O, C-N/N-H, and C-O-C played major roles in the adsorption of Zn2+. Our study of the dually functioning strain SDB4 provides a potential application for the simultaneous biological removal of antibiotics and heavy metals.

Kinetic study of real landfill leachate treated by non-thermal plasma (NTP) and granular sequential batch reactors (GSBR)

The biological treatment of landfill leachate is a challenging process due to the high concentration of chemical oxygen demand (COD), nitrogen compounds, and other toxic compounds. Furthermore, nitrification inhibition may occur in landfill leachate due to the high concentration of free ammonia and inhibitors, such as poisonous compounds. Accordingly, this study aimed to use non-thermal plasma and aerobic granules to reduce organic loading rate and heavy metals of landfill leachate. We used a plasma reactor with a working volume of 0.5 l, quartz material for the pretreatment process. According to the results, the plasma reactor was most efficient in removing metals as well as d quasi-metals (e.g., arsenic, antimony, selenium, cobalt, iron, strontium, and silver) and least efficient in the removal of nickel, zinc, aluminum, and manganese. Our findings indicated that the COD removal efficiency decreased from 100% to 98%, from 93.5% to 89.18%, and from 92% to 88%, for 20%, 50%, plus 100% leachate, and three hydraulic retention times (6, 4.5, and 2.1 h), respectively. The amount of organic matter removal was a function of concentration and followed the second-order kinetic (R2 > 0.9) and Stover-Kincannon models (R2 > 0.97). Thus, it could be concluded that aerobic granules could effectively reduce e the organic load, COD, and heavy metals entering a GSBR reactor. Due to the good efficiency of the plasma reactor and GSBR, so we proposed full- scale studies at the landfill site for heavy metal and organic loading reduction. It also presents a new subject of research and concludes with an outlook on future investigation topics, such as different contaminants in leachate of landfills from different areas.

EVALUATION OF REMOVAL OF HEAVY METALS WITH PHYTOMASS ANNUAL HERBS WHEN USING VARIOUS FERTILIZER SYSTEMS

Under the conditions of a lysimetric experiment on podzolic chernozem, it was found that the use of dolomite flour contributed to a decrease in the mobility of metals and their translocation into crop products, which was reflected in a decrease in their removal relative to the background. The use of mineral fertilizers by increasing the yield of phytomass contributed to an increase in the removal of copper, zinc, lead and cadmium from the soil. The largest total removal of copper, zinc, lead and cadmium with the phytomass of annual grasses (8,035 mg/m2) is observed when using a mineral fertilizer system, and the smallest removal of the indicated metals is observed when using lime without manure (5,092 mg/m2).

Laboratory-Scale Bio-Treatment of Real Arsenic-Rich Acid Mine Drainage

Acid mine drainage (AMD) still represents a huge environmental problem. Technical and scientific breakthroughs are still needed to decrease environmental damages, treatment cost, and waste production associated with AMD. The feasibility of combining continuously fed anaerobic sulfate-reducing bioreactor with downstream iron oxidation step was tested, at a laboratory scale, with two types of real arsenic-rich AMD waters from the site of Carnoulès (France), that differed in acidity (pH 3.3 and 4.0), arsenic (As, 18 and 174 mg.L−1), and metal concentrations. Iron remained in solution, while up to 99% of As was precipitated as amorphous orpiment in the anaerobic sulfate-reducing bioreactor. Zinc (Zn) precipitation was also observed, up to 99%; however, the efficiency of Zn precipitation was less stable than that of As. The anaerobic bioreactor presented a stable bacterial community including a Desulfosporosinus-related sulfate reducer. When the effluents from the anaerobic process step were treated in a laboratory aerobic bioreactor, iron was oxidized efficiently. The feasibility of efficient orpiment bio-precipitation coupled with downstream iron oxidation was shown, thus opening the perspective of a low-cost combination of treatment steps for the removal of arsenic, zinc, and iron in As-rich AMDs.

Zinc and cadmium adsorption from wastewater using hydroxyapatite synthesized from flue gas desulfurization waste.

The purpose of this work is to produce an alternative cost-effective adsorbent to remove zinc and cadmium from wastewater using hydroxyapatite (HAP) synthesized with hydrothermal method from FGD (Flue gas desulfurization) waste generated by two different coal power plants. The effects of FGD type (Cayırhan and Orhaneli) and molar ratio (H3PO4/CaSO4) (0.6-4.79) on HAP synthesis were investigated. Afterwards, effects of the adsorbent dose (1-2 g/L), heavy metal concentration (30, 40, 50 mg/L) and contact time (1, 2, 3, 4 h) on zinc and cadmium adsorption yield from synthetic wastewater using produced HAP were examined. FGD waste and synthesized FGD-HAP were characterized by X-Ray Diffraction (XRD), Fourier Transformed Infrared Spectroscopy (FT-IR), Scanning Electron Microscope (SEM) and Brunauer-Emmett-Teller (BET) instruments. The zinc and cadmium concentration was studied by Inductively coupled plasma atomic emission spectroscopy (ICP-AES). Maximum zinc adsorption capacity of the Cayırhan FGD-HAP was 49.97 and 49.99 mg/L, Orhaneli FGD-HAP was 49.96 and 49.99 mg/L, for 1 g/L and 2 g/L adsorbent dose, respectively, for 50 mg/L heavy metal concentration and 4 h contact time. Maximum cadmium adsorption capacity of the Cayırhan FGD-HAP was 39.98 and 39.99 mg/L, Orhaneli FGD-HAP was 40 and 39.99 mg/L, for 1 g/L and 2 g/L adsorbent dose, respectively, for 40 mg/L heavy metal concentration and 4 h contact time. Adsorption yields were calculated between 98.53% and 100%. The adsorption data were well explained by a second-order kinetic model, and the Freundlich isotherm model fits the equilibrium data. The adsorption results demonstrated that FGD's waste is an effective source to synthesize HAP, which is used as an adsorbent for zinc and cadmium removal from wastewater due to high adsorption capacity.

Zinc Removal Mechanisms with Recycled Lignocellulose: from Fruit Residual to Biosorbent then Soil Conditioner

Zinc Removal Mechanisms with Recycled Lignocellulose: from Fruit Residual to Biosorbent then Soil Conditioner

Biosorption potential of brown algae, Sargassum polycystum, for the removal of toxic metals, cadmium and zinc.

In this research work, the biosorption potential of brown algae, Sargassum polycystum, was investigated for the removal of toxic metals, cadmium (Cd) and zinc (Zn), under controlled environmental conditions. The biosorbent prepared from the S. polycystum was characterized by Brunauer-Emmett-Teller (BET), scanning electron microscope (SEM) and Fourier transform infrared spectroscopy (FTIR) techniques. The optimal conditions identified using Box-Behnken design (BBD) for Cd removal were pH: 4.65, biosorbent mass: 1.8 g/L and shaking speed: 76 rpm. For zinc, the optimum values were pH: 5.7, biosorbent mass: 1.2 g/L and shaking speed: 125 rpm, respectively. The equilibrium uptake of the metals, Cd and Zn, was evaluated by isotherm models. The Langmuir isotherm proved to be an excellent fit confirming single layer of sorption. The maximum Cd and Zn uptakes achieved were 105.26 mg/g and 116.2 mg/g respectively. The kinetics of Cd and Zn biosorption onto brown algae Sargassum polycystum, follows pseudo-second order. The thermodynamic parameters were determined, and the sorption process was found to be feasible. Desorption studies of Cd and Zn were performed, and the bio sorbent reproduced appreciable efficiency for five successive cycles of sorption-desorption process using HCl.