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This study aims to determine the sorption isotherms of three tropical woods from Cameroon to understand the conditions for their use and drying. The equilibrium moisture contents were experimentally determined using saturated salt solutions. Some anatomical parameters were also measured to assess the influence of the structure of these woods on their sorption behaviour. Among the sorption models tested, the Guggenheim-Anderson-de Boer model is the one that best fits the experimental points. Our results also reveal a strong correlation between EMCs and the size and number of anatomical parameters. Indeed, up to 40°C, Sipo which has the lowest wood density and larger vessel sizes and rays, contains more water at equilibrium that the two other woods. When temperatures increase above 50°C, Sapelli becomes more hygroscopic due to the expansion of its lumen cells. These findings highlight the need for specific data on the sorption behaviour of Central African woods, to efficiently manage their drying and use. [ABSTRACT FROM AUTHOR]

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This study aimed to determine the desorption isotherms and the thermodynamic properties of taioba leaves. For this, gravimetric-static method was used to determine the equilibrium moisture content (EMC) and water activity of taioba leaves at nine storage and drying temperatures (5–80 °C). The proximate composition was also determined. The Clausius-Clapeyron and Gibb's-Helmholtz equations were used to determine the net isosteric heat of desorption and differential entropy, respectively. The enthalpy-entropy compensation theory was also investigated. The relationship between water activity and equilibrium moisture content was best described by GAB model (R a d j 2 ≥0.987; χ2.105≤3.126; RMSE≤0.006) for the whole range of relative moistures and temperatures. The sigmoid-shaped type II was predominant at all temperatures. The net isosteric heat of desorption decreased from 8907.62 to 1120.15 J/mol as the moisture content increased. The linear relationship between enthalpy and entropy endorsed the enthalpy-entropy compensation mechanism in which T B > T hm , thus, an enthalpy-driven process. The free Gibbs energy was less than zero spontaneous (ΔG Bstorage = −728.79 J/mol and ΔG Bdrying = −1217.20 J/mol), indicating that water desorption is spontaneous. The spreading pressure varied from 0.001 to 0.05 J/m2 for all temperatures studied. The water surface area tended to decrease with increasing temperature, ranging from 185.71 to 251.97 m2/g. Therefore, this study provided an understanding of the water desorption properties of taioba leaves, contributing to the development of storage and drying practices. [ABSTRACT FROM AUTHOR]

Milled olive stones are evaluated as a biosorbent for the removal of heavy metals such as Cd (II), Cu (II), Pb(II) and Cr(VI) from aqueous effluents. To this end, thermodynamic and kinetic studies for single and multimetal systems are performed through batch equilibrium isotherms. The biosorbent was characterized by elemental and FTIR analysis and scanning electron microscopy. The effect of the different parameters, such as contact time, pH, amount of adsorbent and initial metal concentration, on the sorption process is also investigated. The maximum removal percentage for 1 mg L−1 of cadmium, copper, and lead was 77.4%, 80.5%, and 94.5%, respectively, at pH 6 with 5 g L−1 of sorbent. In the case of Cr(VI), a removal percentage of 46% was obtained in 2 h at pH 2 using a larger amount of sorbent (10 g L−1) and an initial concentration of 2 mg L−1. Equilibrium data were analyzed by applying different adsorption isotherm models, resulting in—a good agreement with—the Langmuir model with maximum capacities of 0.557, 0.3 and 0.581 mg g−1 for Cu(II), Cd(II) and Pb(II), respectively, whereas for Cr(VI), the Temkin model provided the best fit with a maximum capacity of 2.34 mg g−1. The kinetic data fitted well into the pseudo-second-order model which allowed the adsorption rate constants to be calculated. Cd(II) resulted to have the highest kinetic constant, followed by Cu(II), Cr(VI) and Pb(II). The results showed that milled olive stones can be used as a biosorbent for the removal of these metals from aqueous solutions. Article Highlights: Trace concentrations of Cu(II), Cd(II), Pb(II), and Cr(VI) were adsorbed by olive stones. Removals of 77.4%, 80.5 and 94.5% were obtained for Cu(II), Cd(II), or Pb(II) at pH 6. For Cr(VI), a removal percentage of 46% was obtained at pH 2 with 10 g L−1 of sorbent. Langmuir isotherm model was fitted to Cu(II), Cd(II), and Pb(II) adsorption isotherm data. Cd(II) has the highest pseudo-second-order kinetic constant, followed by Cu(II), Cr(VI) and Pb(II). Milled olive stone is an effective and cheaper biosorbent to remove toxic metals. [ABSTRACT FROM AUTHOR]

New titanium phosphates were synthesized and tested as potential sorbents for europium from aqueous solutions. The experiments were undertaken in the concentration region 50–2000 mg L −1 at pH 5 without and with background electrolyte. The uptake data were determined by γ-spectroscopy with 152 Eu as tracer and fitted by the Langmuir, Freundlich and Temkin models. The new materials showed high sorption capacities (up to 259.6 mg g −1 ) as derived from the Langmuir equation. Investigation of the sorption kinetics took place at 293, 303, 313 and 323 K. It was demonstrated that Eu-sorption proceeds very fast and described by pseudo-second-order kinetics while the rate constant and activation energy were calculated. Infrared and Raman spectroscopy, scanning electron microscopy and X-ray diffraction were applied for the sorbents characterization. Leaching tests were performed to assess the environmental compatibility of the loaded sorbent as well as desorption tests. The obtained data indicated that the interaction of the synthesized titanium phosphates with the Eu-solutions is a complex phenomenon based on ion exchange and formation of inner-sphere complexes. [ABSTRACT FROM AUTHOR]

In this study, a novel composite material was synthesized by impregnating titania coated silica microsphere functionalized with potassium ferrocyanide in calcium alginate for highly efficient uptake of Cs isotopes from aquatic environment. In order to enhance the stability of silica microsphere, titania was coated over silica microsphere by using sol-gel process. To enhance the exchange capacity of titania coated silica microsphere for Cs, it was functionalized with potassium ferrocyanide. The whole assembly was impregnated in calcium alginate in order to remove the 134+137 Cs from potable water without altering drinking water quality parameters. Experiments were conducted by spiking the groundwater and seawater in the concentration range of 1000–50,000 BqL −1 . Removal efficiency of more than 99% and 97% were observed in case fresh water and marine environment respectively. Sorption capacity of the material was evaluated by using stable Cs. Maximum sorption of Cs was seen at the pH range 7.5–8.5 and the equilibrium time required for the removal of Cs was 24 h. Kinetic models and adsorption isotherm equations (Langmuir & Freundlich) were used to fit the experiment data for describing the sorption process. The maximum sorption capacity of the beads is 23.55 mg g −1 in case of stable Cs and the sorption follows the Langmuir isotherm. From the kinetic study it was observed that the reaction is following the pseudo first order kinetic equation. [ABSTRACT FROM AUTHOR]

Basic laws of static ion exchange of copper cation (II) zinc from aqueous caustic by natural mineral kaolinite were investigated. Quantitative characteristics of sorption process of copper ions and zinc were obtained. The sorption capacity of kaolinite was studied at temperatures of 298, 318, and 333K (mmol/g): for copper ions of 0.55 (at 298K) 0.60 (318K), 0.70 (333K), and for zinc ions of 0.38 (298K), 0.45 (318K), 0.53 (333K). The nature of interaction between the sorbate and sorbent is established. Balance of copper and zinc ions exchange on kaolinite by method of isotherms creation was investigated. It is established that isotherms belong to Lengmuir isotherms and according to BET classification they have the I type at copper ions sorption, and the IV type at zinc ions sorption. It is shown that the sorption parameter of interaction (K) characterizes the energy of interaction of copper ions with the sorbent. [ABSTRACT FROM AUTHOR]

Various azodyes containing one or more sulfonic groups were removed from aqueous solutions by biosorption on untreated wood shavings from Picea abies. The sorption kinetics was described by the pseudo-first-order (PFO), pseudo-second-order (PSO) and modified pseudo-n-order (MPnO) equations, from which the MPnO model provided the best fit to the experimental data. The surface reaction was identified as a rate-limiting step governing the dye sorption on wood shavings, but a mixed kinetics (with a significant role of diffusional processes) may occur in certain stages of the dye sorption process. The removal efficiencies differed markedly in dependence on the dye structure. Although electrostatic interactions play certainly a significant role in the sorption of sulfonic dyes, the differences in the sorption efficiencies may be explained as a result of different hydrophobic interactions that occur between less-polar parts of the dye molecule (aromatic rings) and hydrophobic domains in the wood matrix. With some limitations, the sorption behavior of the azodyes can be predicted from their structural parameters using the Gibbs energy of hydration as an estimator. [ABSTRACT FROM AUTHOR]

A composite sorbent (MGMA) was synthesized by coating a magnetite core with glycidyl methacrylate-based polymer, further grafted with diethylenetriamine (DETA). The absence of coercivity and remanence in VSM analysis confirms that the material has super paramagnetic properties that make it readily separable from the liquid phase applying external magnetic field. The sorbent (MGMA-DETA) was tested for Hg(II) recovery from aqueous solutions (of increasing complexity). The separation of Hg(II) from multi-metal solutions was tested at different pH values. The impact of counter ions on metal sorption was also tested at different pHs. Sorption mechanisms explained the different effects of counter ions (in relation with metal speciation) and also the relative selectivity of the sorbent for Hg(II) over other base metals. Uptake kinetics and sorption isotherms were modeled with the pseudo-second order rate equation and the Langmuir equation, respectively. The thermodynamic parameters have been calculated. The sorbent was successfully tested for Hg(II) removal from two industrial effluents (from chlor-alkali industry and from mercury-oxide manufacturing). The sorbent could be recycled for at least 4 cycles of sorption/desorption. This means that the magnetic sorbent is a promising material for the efficient and selective removal of mercury from complex solutions. [ABSTRACT FROM AUTHOR]

High total and bioavailable concentrations of As in soils represent a potential risk for groundwater contamination and entry in the food chain. The use of organic amendments in the remediation of As-contaminated soils has been found to produce distinct effects on the solubility of As in the soil. Therefore, knowledge about As adsorption-desorption processes that govern its solubility in soil is of relevance in order to predict the behaviour of this element during these processes. In this paper, the objective was to determine As adsorption and desorption in four different soils, with and without compost addition, and also in competition with phosphate, through the determination of sorption isotherms. Batch experiments were carried out using three soils affected differently by previous mining activity of the Sierra Minera of La Unión-Cartagena (SE Spain) and an agricultural soil from Segovia province (central Spain). Adsorption was higher in the mining soils (and highest in the acidic one) than in the agricultural soils, although the latter were not affected negatively by organic matter or phosphate competition for sorption sites. The results show that As adsorption in most soils, both with and without compost, fitted better a multimolecular layer model (Freundlich), whereas As adsorption in competition with P fitted a monolayer model (Langmuir). Moreover, the use of compost and phosphate reduced the adsorption of As in the mining soils, while in the agricultural soils compost increased their low adsorption capacity. Therefore, the use of compost can be a good option to favour As immobilisation in soils of low adsorption, but knowledge of the soil composition will be crucial to predict the effects of organic amendments on As solubility in soils and its associated environmental risk. [ABSTRACT FROM AUTHOR]

We have studied the pH and the temperature effects on copper ions' adsorption on natural and treated clays from Algeria. The clay was also treated to improve the adsorption capacity. X-ray diffraction identified montmorillonite and kaolinite as major clay minerals. The Langmuir adsorption model was used for the mathematical description of the adsorption equilibrium and the equilibrium data adhered very well to this model. The treated and natural clay had a monolayer adsorption capacity equal to 15.40 and 12.22 mg/g, respectively, at pH value of 6.5 and temperature 20 ° C, the adsorption isotherms could be fitted with Langmuir isotherms, and the coefficients indicated favorable adsorption of Cu(II) on the clays. Determination of the thermodynamic parameters, H, S, and G showed that the adsorption process was spontaneous and exothermic accompanied by a decrease in entropy and Gibbs energy. Results of this study will be useful for future scale-up for using this material as a low-cost adsorbent for the removal of Cu(II) from wastewater. [ABSTRACT FROM AUTHOR]

The potential effect of urban particulate matter (PM) accumulation on metal sorption onto two contrasting soils (Chernozem and Fluvisol) was investigated in a batch sorption experiment. While the Freundlich isotherms did not indicate any effect of PM addition to the soils, the Langmuir isotherm allowed us to estimate the potential behaviour of the PM in the soil. The PM added to the Chernozem did not lead to substantial changes in sorption of Cd, Cu, Mn, Ni, Pb, and Zn. On the contrary, the presence of PM in the Fluvisol increased the number of potential sorption sites in the soil. However, the results of the approximation showed a lower affinity of Cd, Mn and Ni for the Fluvisol and a better stability and a lower bioavailability of these elements in the Chernozem. In the case of Pb and Cu, no significant changes were observed in PM-enriched soils regardless of the soil properties. [ABSTRACT FROM AUTHOR]

The sorption isotherm of porous building material is basic information needed for the design and maintenance of materials. The equilibrium moisture content (EMC) method is used to determine this physical property. In this study, the equilibrium relative humidity (ERH) method was used to determine the adsorption data for autoclaved aerated concrete at seven temperatures and found that the ERH method could be used to determine the sorption data within a short time. Comparing with previous published data, no significant difference could be found at humidity >20%. Two different sizes of samples (small and large) revealed the same EMC data throughout the whole relative humidity (RH) range. The Oswin equation was the best ERH model for adsorption isotherm data. A temperature term could be incorporated into model for the adsorption data. Sorption isotherm data for other building materials could be determined with the ERH method. [ABSTRACT FROM AUTHOR]

Moisture sorption isotherms of persimmon leaves were determined at 20, 30 and 40 °C using the standard gravimetric static method over a range of relative humidity from 0.06 to 0.9. The experimental sorption curves were fitted by seven equations: Henderson, Halsey, Smith, Oswin, BET, GAB and Caurie. The Halsey, Smith, GAB and BET models were found to be the most suitable for describing the sorption curves. The isosteric heat of sorption of water was determined from the equilibrium data at different temperatures. It decreased as moisture content increased and was found to be a polynomial function of moisture content. [ABSTRACT FROM AUTHOR]

Abstract: Unfired clay masonry has a high potential to regulate indoor humidity and therefore create healthier living environments. The measurement of such potential on various building materials has received increasing attention and has generated the Moisture Buffering Value (MBV) concept. This work experimentally explored various conditions affecting the measurement and calculation of the buffering potential. Measurements of MBV and steady state properties (water vapour permeability and sorption isotherms) were performed on 18 samples, Compressed Earth Blocks (CEB) and Stabilised Compressed Earth Blocks (SCEB). It is quantitatively shown how the variability of experimental conditions in the dynamic measurement can change the obtained MBV (MBVpractical). The calculated buffering potential (MBVideal) is equally affected by the variability of the steady state properties measurements. A good agreement between calculated and measured MBV was observed for most samples when reducing this variability which was shown by using a DVS (Dynamic Vapour System) system to obtain the sorption isotherms of the material. [Copyright &y& Elsevier]

Abstract: The application of low cost materials in wastewater treatment has recently attracted great interest; fly ash and slag have improved high performance as a low cost material and have been used as a potential adsorbent for removal of phosphate, heavy metals and organic pollutants in wastewater treatment. Batch adsorption experiments were performed in order to evaluate phosphate removal efficiency of slag and fly ash. The effect of various operating variables, i.e. initial pH, adsorbent dose, initial metal ion concentration, and adsorption time of phosphate using the slag and fly ash, has been studied. The sorption process was relatively fast and equilibrium has been reached at 30min contact time and the maximum removal percentage was achieved at an adsorbent loading weight of 0.5gm/100ml. Phosphate removal ratio using slag and fly ash was 93% and 95%, respectively, under the batch test conditions. The overall uptake for the slag was maximum at pH 5 and at pH 7 for fly ash. The sorption data were represented using Freundlich and Langmuir parameters, where the sorption data were better represented by the Freundlich isotherm than by the Langmuir. The optimized method was applied for phosphate removal from wastewater of Proctor and Gamble (P&G) Company for household products. The achieved phosphate removal efficiency was 96.15% and 96.9% using slag and fly ash respectively. [Copyright &y& Elsevier]

Abstract: Poly(d,l-lactide-co-glycolide) (PLGA) and polyvinyl alcohol (PVA) were used to prepare the electrospun fibers membranes (EFMs) by electrospinning, respectively. These EFMs were used to adsorb perfluorooctane sulfonate (PFOS) from aqueous solution. The sorption kinetics and isotherms of PFOS on EFMs were investigated. The pseudo-first-order model (PFOM) can well describe the sorption kinetics of PFOS on these two types of EFMs. The experimental results show that the sorption capacities of PFOS on PLGA and PVA EFMs are 77.29 and 337.77μg·g-1, respectively. The main sorption mechanisms of PFOS on PLGA EFMs are pore-filling. Moreover, hydrogen bonding interactions exist in the sorption processes of PFOS on PVA EFMs. [Copyright &y& Elsevier]

Abstract: In this study, three of the main physical properties of green roofs were experimentally investigated to determine some of the key green roof modeling parameters. First, the thermo-physical properties of green roofs were characterized by correlating the thermal conductivity of the substrate with the water content for different substrates and maximum water capacities. Next, the moisture storage was characterized using the dynamic vapor sorption technique to determine both the sorption and desorption isotherms for three different temperatures as well as the moisture buffer capacity. Third, the micro-structural properties of green roof substrate were characterized using mercury intrusion porosimetry to measure the porosity range of the substrate and to compare this porosity range with different concrete porosities. In addition to these characterizations, the evapotranspiration term, which is very important in the water balance, was measured. The few studies found in literature provide the expression of the evapotranspiration term for a watered grass and vegetated areas on a large scale. In this study, this term is expressed for the experimentally studied green roof complex (substrate + vegetation). The ultimate objective of these experiments is to estimate the parameters used as input data in the developed green roof model to evaluate the energy performance of a building. [Copyright &y& Elsevier]

Abstract: This work presents a study on the reuse of spent bleaching earth (SBE). The SBE waste was regenerated by impregnation in NH4Cl solution followed by heat treatment at 400°C and washing with 1M HCl. The regenerated material (RSBE) was used in the treatment of a basic textile dye solution. Results showed that the adsorption phenomenon governing this process was best described by the Langmuir model. The adsorption kinetic process was found to follow a pseudo second order model. [Copyright &y& Elsevier]

Abstract: The moisture contents of balance of desorption and adsorption of Kabar Sid El Cheikh leaves (Capparis spinosa .L) were determined at 30, 40, and 50°C using the static gravimetric method. The balance was obtained after 12 days of desorption and 8 days of adsorption. The effect of thermal hysteresis is observed in the range of the tested temperatures. In one hand, for the modeling of sorption isotherms, on the other hand, for the prediction of the hygroscopic behavior, during storage or drying; two mathematical models were tested. The GAB model with three parameters has given best results according to the experimental points in a rather important domain of the activities of the water. [Copyright &y& Elsevier]

The batch removal of ammonium ions from aqueous solutions under different experimental conditions using (Al)Si-MCM-41 mesoporous molecular sieve in comparison with LTA microporous zeolite was investigated in this study. The ammonium uptake was dependent on the initial ammonium concentration. The equilibrium sorption data were fitted using Freundlich and Langmuir isotherm models. The Langmuir model (monolayer sorption) gave the best fit (R² = 0.9965 for (Al)Si-MCM-41 and R² = 0.9995 for LTA). The saturation capacity (monolayer coverage) was found of 33.33 mg NH4+/g (Al)Si-MCM-41 and 55.55 mg NH4+/g LTA. Equilibrium sorption was reached at about 25 min on (Al)Si-MCM-41 and at about 60-90 min in the case of LTA molecular sieves. The kinetic data showed that the sorption rate could be better described by pseudo-second order model. [ABSTRACT FROM AUTHOR]

The study reports on the removal of Cd, when present singly or in binary (Cd+Pb, Cd+Ni) and ternary systems (Cd+Pb+Ni), by black gram husk (bgh) in a stirred tank bioreactor. The biosorbent removed Cd and other heavy metal ions effectively from aqueous solutions with selectivity order of Cd>Pb>Ni. The biosorption of Cd by bgh increased with initial metal and biosorbent concentrations. The biosorption capacity of bgh was affected by the change in stir- ring speed of the tank bioreactor. The sorption was noted to be rapid within the first 20 min, and a residual Cd concentration of 2% could be achieved after 30 min at 1000 rpm, 45 min at 750 rpm, or 60 min at 500 rpm. The biosorption of Cd was found to be pH-dependent, and maximum adsorption occurred at solution pHs of 4-6. The maximum amount of Cd (qmax) adsorbed at equilibrium was 46.52 mg/g dry biomass, which was well described by Langmuir and Freundlich adsorption isotherms. Efficiency of biosorbent to remove Cd from binary and ternary solutions with Pb and Ni was not significantly interfered. The results suggest that bgh can be used as a biosorbent in stirred tank reactors on large scale for an efficient removal of Cd from wastewaters containing heavy metals in multimetal situations. [ABSTRACT FROM AUTHOR]

The amount of water available in food for enzymatic and oxidative reactions as well as for microbiological proliferation is an important factor in the conservation, storage, and development of new food products. Adsorption and desorption steps at different temperatures act as important parameters used to further understand the behavior, response, and interference of moisture in the technological properties of food. This behavior can be observed using sorption isotherms. The use of by-products from maize processing has increased. Obtaining food from these materials depends on the technological analysis of these raw materials. The objective of this study was to show the benefits of a predictive experimental model of the sorption behavior of flours obtained from two different by-products of waxy corn wet-milling using the Dynamic Dewpoint Isotherm (DDI) method. The sorption profiles of flours at 20, 30, and 40 °C were estimated and mathematically fitted to different models. This study showed type III sorption curves (Thommes et al., 2015) behavior for both flours and the mathematical adequacy of different models. Numerical math methodology, with validated statistics, showed that the Peleg model is the best fit. The net isosteric heat of sorption estimated using the Clausius–Clapeyron equation, decreased in both flours when the moisture content of samples increased. Residual pattern analysis and linear graphical correlation of predicted models and experimental data showed that the scoring method using the interpolation of data obtained in the analyses of statistical factors and segregation using Sturges' rule, is a viable way to determine the most suitable mathematical model to describe sorption curves. [ABSTRACT FROM AUTHOR]

A high-energy ball milling of magnetite nanoparticles with amino-phosphonic functionalized poly(glycidyl methacrylate) polymer is used for manufacturing a highly efficient magnetic sorbent for U(VI) sorption from aqueous solutions. The Uranyl ions were adsorbed through the binding with amine and phosphonic groups as confirmed by Fourier Transform infrared (FTIR) and X-ray photoelectron spectroscopy (XPS) analyses. The maximum sorption capacity (up to 270 mg U g−1) occurred at pH = 3–4; Langmuir isotherm well describes the sorption process. Small-size particles allow achieving fast uptake (within ≈90 min of contact); and the kinetic profiles are modeled by the pseudo-second order rate equation. Uranium is successfully desorbed from loaded sorbent using 0.25 M NaHCO 3 solution: Sorbent can be recycled with minimal decrease in sorption and desorption efficiency for at least 6 cycles. The sorbent is efficiently used for U(VI) recovery from the acidic leachates of U-bearing ores (after precipitation pre-treatment). Sorption capacity approaches 190 mg U g−1 despite the presence of high concentrations of Fe and Si: the sorbent has a marked preference for U(VI) (confirmed by distribution ratios and selectivity coefficients). The uranium sorption by solid-state-synthesized PPA-PGMA/Fe 3 O 4 nanocomposite. Image 1 • New core-shell multifunctional magnetic-nanocomposite for enhanced uranium binding. • Maximum sorption capacity reaches 262.5 mg U g−1. • High stability in recycling and good selectivity against base metals. • Efficient testing on sulfuric-acid uranium leachates of the El-Sella mining area. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Aloe-Vera is proposed as a potential biosorbent for U and Cd in acidic solutions. • Modification of the raw material by NaOH enhances significantly its sorption capacity. • Application of several kinetic models indicates the complexity of the sorption mechanism. • Mechanism involves physical sorption, ion exchange, complexation and surface precipitation. Abstract The biosorption of uranium and cadmium using Aloe vera wastes was investigated regarding the effect of pH, sorbent mass, concentration, contact time and temperature. Additionally, modification of the raw material by acidic and alkaline reagents was carried out in order to enhance its sorption ability for the tested metals. Several models as pseudo-first and pseudo-second order equation as well as Elovich and intra-particle diffusion model were satisfactorily applied to reproduce the kinetics data indicating the complexity of the sorption mechanism. The sorption isotherms were simulated by Langmuir and Freundlich models and thermodynamic data were determined in order to assess the uptake behavior. It was found that the biosorbent modified by alkaline reagent, exhibited high sorption capacity with q max values, 370.4 and 104.2 mg g−1 for uranium and cadmium respectively. TCLP tests for the investigation of environmental compatibility of the loaded biosorbents and desorption tests were also performed. Furthermore, SEM/EDS, XRD and FTIR were used for the characterization and elucidation of the sorption mechanism which is complex and involves different mechanisms as physical sorption, ion-exchange, metal binding and surface precipitation. [ABSTRACT FROM AUTHOR]