Tea waste-derived biochar magnetically modified with CoFe 2 O 4 enables ultrafast and efficient solid-phase extraction of Cd( ii ), Pb( ii ), and Ni( ii ) ions from environmental waters, offering a low-cost and sustainable adsorbent.
In this research, within the framework of a waste-to-resource conversion approach, biochar obtained from spent tea waste (STWB), a widely available and cost-free biomass source, was modified with magnetic CoFe2O4 nanoparticles to develop an environmentally friendly adsorbent (CoFe2O4/STWB). The applicability of this material for efficient separation and preconcentration of Cd(II), Pb(II), and Ni(II) ions from mining wastewater, stream water, and wastewater samples collected from an organized industrial zone was systematically investigated using the solid phase extraction (SPE) method. Optimization of the experimental variables was conducted to enhance the extraction performance of the target analyte ions. The fact that the adsorption and desorption equilibrium times occur in less than 1 min demonstrates the rapid and highly efficient extraction performance of the developed adsorbent. Langmuir isotherm model analysis revealed that CoFe2O4/STWB exhibits adsorption capacities of 69.4 mg g-1 for Cd(II), 185.2 mg g-1 for Pb(II), and 45.2 mg g-1 for Ni(II). In contrast, the corresponding adsorption capacities obtained for unmodified STWB were considerably lower, with values of 42.9, 75.8, and 16.8 mg g-1 for Cd(II), Pb(II), and Ni(II), respectively. These results clearly demonstrate that modification with CoFe2O4 significantly enhances the adsorption performance of STWB. Consequently, CoFe2O4-modified spent tea waste can be regarded as an effective, economical, and sustainable adsorbent for trace heavy metal analysis in environmental water samples, owing to its rapid extraction kinetics, high adsorption capacity, and low detection limits.
In the present research, a novel cloud point extraction (CPE) method was developed for the separation and preconcentration of toxic Cu(II), Ni(II), Pb(II), and Cd(II) ions in environmental water and vegetable samples, prior to their determination by flame atomic absorption spectrometry (FAAS). The ligand 2-(2-(4-fluorobenzyl)-1H-benzo[d]imidazole-1-yl)acetohydrazide (FB-BIAH) was employed for the first time as an analytical complexing agent for the aforementioned metal ions, and Triton X-114 (TX-114) was preferred as the nonionic surfactant. Within the scope of optimizing CPE conditions, experimental parameters, such as pH, FB-BIAH and surfactant amounts, and incubation temperature and time, as well as centrifugation speed and duration, were systematically investigated. The optimal conditions for the simultaneous quantitative recovery of analyte ions were established as pH 7.0, an FB-BIAH amount of 2.5 mg, a TX-114 quantity of 25 mg, an incubation temperature of 60 °C, and an incubation time of 30 min. Under optimal conditions, the proposed method was successfully applied to river water and seawater, as well as different vegetable samples such as lettuce, parsley, and pepper. The results obtained demonstrated that the analyte ions could be reliably determined in complex matrices and that the method exhibited high analytical performance. Due to its simplicity, rapid applicability, environmentally friendly nature, and cost-effectiveness, the proposed CPE-FAAS method represents a promising approach for the routine analysis of toxic heavy metals in environmental water and food samples.
Brevibacillus agri was immobilized onto an abundant natural clay through a simple synthesis route to develop a novel and efficient adsorbent for the removal of Pb(II) ions from aqueous media. The adsorption behavior of Brevibacillus agri-loaded clay (BLC) was evaluated using batch experiments by investigating the effects of initial solution pH, BLC dosage, contact time, initial Pb(II) concentration, temperature, and the presence of foreign ions. The optimum conditions were determined to be an initial solution pH of 5.0 and a contact time of 120 min. Isotherm models were applied to elucidate the interactions between Pb(II) ions and BLC, while kinetic studies were conducted to evaluate the adsorption performance and underlying mechanisms. The maximum adsorption capacity of BLC was 65.4 mg g-1. Thermodynamic parameters revealed that Pb(II) adsorption on BLC was exothermic, feasible, and spontaneous at 25ºC. Artificial neural network (ANN) studies provided highly accurate predictions by modeling and confirmed the reliability and applicability of the model for Pb(II) removal in industrial applications. This study presents an innovative and sustainable approach for heavy metal removal, offering an effective solution applicable to environmental remediation processes.
A carrier element-free coprecipitation (CEFC) method was developed for the preconcentration and determination of trace Co(II) and Cu(II) in environmental and food samples using a novel thiosemicarbazone-derived Schiff base ligand (MBITAH). Unlike conventional coprecipitation approaches, the proposed strategy eliminates the need for inorganic carriers, reducing potential interferences and improving selectivity toward the target analytes. Under optimized conditions (pH 7.0, 1.5 mg ligand), quantitative recoveries were achieved with limits of detection of 1.16 and 0.79 µg L⁻1 for Co(II) and Cu(II), respectively. A preconcentration factor of 50 enabled sensitive determination by flame atomic absorption spectrometry (FAAS) with good precision (RSD ≤ 3.7
The sustainable valorization of agro-industrial residues into high-performance adsorbents, combined with reliable adsorption modeling, represents a promising strategy for wastewater treatment. In this study, a high-surface-area activated carbon (SBET = 984 m2 g-1) was synthesized from tea industry waste via KOH-assisted chemical activation and applied for methylene blue removal from aqueous solutions. The adsorbent exhibited excellent performance, achieving a maximum experimental adsorption capacity of 344.5 mg g-1. Beyond material development, a transparent framework for adsorption model evaluation is proposed. Kinetic and equilibrium data were analyzed using linear, nonlinear, and pseudo-linear regression approaches. For multi-parameter isotherms, explicit linear forms were combined with nonlinear estimation to construct a reproducible pseudo-linear strategy. Nonlinear optimization employed five error functions (SSE, ARE, MPSD, HYBRID, and MAE). To enable objective comparison, errors were normalized and aggregated as the Sum of Normalized Errors (SNE), and model selection was based on the Normalized Total Error (NTE). Results showed that nonlinear and pseudo-linear approaches outperform linear regression, while the Avrami model best describes adsorption kinetics, indicating heterogeneous mechanisms. The proposed framework offers a systematic and reproducible methodology for reliable adsorption modeling. This approach enhances comparability across studies and reduces subjectivity in model interpretation and decision making. Environmental implication: This study demonstrates the sustainable valorization of tea industry waste (TIW) into a high-performance activated carbon for the efficient removal of hazardous dyes from aqueous systems. By converting large-scale agricultural residues into value-added adsorbents, the proposed approach reduces solid waste burden while supporting circular economy principles. The synthesized material exhibits high adsorption capacity (344.5 mg g-1) and favorable kinetics, highlighting its practical applicability and scalability for industrial wastewater treatment. In addition, the applied modeling approach improves the reliability of adsorption data interpretation and supports the design and optimization of adsorption systems for the removal of persistent organic pollutants from water.
The tea industry generates substantial quantities of solid waste with limited high-value industrial applications. In this study, tea industry waste was converted into boric acid-activated carbon (BA-TAC) through a simple one-step chemical activation process and evaluated as an adsorbent for phenol removal from aqueous solutions. BA-TAC exhibited a mixed micro-mesoporous structure with a BET surface area of 592.59 m2 g-1. The adsorption performance was investigated as a function of solution pH, contact time, and initial phenol concentration. Adsorption kinetics were evaluated using pseudo-first order, pseudo-second order, Elovich, Avrami, and intraparticle diffusion models, whereas equilibrium data were analyzed using Langmuir, Freundlich, and Sips isotherms. Linear, pseudo-linear, and non-linear regression approaches were comparatively evaluated, demonstrating the limitations of conventional linearization and the superiority of direct non-linear regression. Moreover, the so-called linearized forms of multi-parameter models such as Sips are not truly linear because iterative parameter estimation remains necessary. The maximum experimental phenol adsorption capacity reached 101.80 mg g-1 despite the moderate BET surface area of BA-TAC. The experimentally determined natural pH and pHpzc values, together with the limited desorption efficiency, indicated that adsorption was governed predominantly by surface chemical interactions rather than electrostatic attraction alone. XPS analysis confirmed the incorporation of boron-containing surface functionalities, highlighting their contribution to phenol adsorption. Overall, this study demonstrates the successful valorization of tea industry waste into a functional boron-modified activated carbon while providing methodological guidance for reliable adsorption kinetics and equilibrium modeling, thereby supporting sustainable waste valorization.
Turkey, located within the Western Asia gene center, is a significant genetic center for many fruit species, including pears. Rize, a province in the Northeastern part of Turkey, is located within the Northeast Anatolia Region, which falls within the genetic center area where pears have undergone evolutionary development. This study aimed to identify promising local Egrisap pear clone genotypes with superior traits and to introduce them into economic use. For this purpose, Rize province and its districts were surveyed, and fruit and leaf samples were collected from pre-selected Egrisap pear clone types. These samples were subjected to pomological, morphological, and chemical analysis. The JMP 13 statistical software package was used to compare the Egrisap pear clone types. According to the research results, the pomological and morphological traits of the clone types varied as follows: fruit weight (99.10-139.54 g), fruit width (54.52-65.41 mm), fruit length (57.58-68.83 mm), fruit stem length (50.75-59.50 mm), fruit stem thickness (2.36-2.91 mm), core width (5.15-7.55 mm), core length (9.73-14.51 mm), flesh firmness (3.61-7.13 lb), seed number (5.30-8.55), leaf width (45.80-60.04 mm), leaf length (64.53-82.37 mm), petiole length (37.04-60.99 mm), petiole thickness (0.83-1.20 mm), and soluble solid content (SSC) (9.10 %-16.0 %). Regarding chemical composition, the pH values of the clone types ranged from (3.78-4.22), titratable acidity (0.22 %-0.47 %), protein content (1.50 %-4.95 %), vitamin C content (0.92-2.28 mg/100 g), ash content (1.16 %-4.30 %), and total sugar content (9.66 %-17.28 %). Mineral element analysis of the local pear varieties revealed that iron content ranged from (0-14.7 mu g/g), copper (2.90-9.12 mu g/g), manganese (2.9-11.6 mu g/g), magnesium (321.7-771.5 mg/g), zinc (0 mu g/g), sodium (9.6-39.6 mu g/g), potassium (5.43-14.50 mu g/g), calcium (50.1-219.7 mu g/g), cobalt (0.01-0.31 mu g/g), cadmium (0-0.1 mu g/g), and nickel (0.08-4.41 mu g/g). Among the local Egrisap pear clones grown in Rize, clone type 53 IYD 01 was identified as having the most superior quality criteria and chemical composition. Consequently, it is recommended that this clone type be introduced to producers for cultivation. (c) 2025 SAAB. Published by Elsevier B.V. All rights are reserved, including those for text and data mining, AI training, and similar technologies.
The analysis of gold, which is a precious metal with limited resources, in environmental samples is crucial for the sustainable utilization of natural resources. Therefore, in the present research we have aimed to develop a novel and environmentally friendly bioadsorbent, Brevibacillus borstelensis loaded on silica gel (BB@Si), with outstanding adsorptive properties that can be implemented for quantitative recovery of Au(iii) ions via the solid phase extraction (SPE) technique. After characterizing the developed adsorbent using FTIR and SEM techniques, we conducted a detailed investigation of the critical parameters that influence the extraction performance of Au(iii) ions. Optimum parameters were observed as follows: pH 3.0, adsorption contact time 30 min, eluent type 0.1% (w/v) thiourea in 0.5 M HNO3, elution time 60 min, BB@Si amount 1.0 g L-1, and sample volume 400 mL. Some of the well-known isotherm and kinetic models were applied to the results observed from the adsorption studies. Equilibrium adsorption capacity of BB@Si was estimated to be 66.2 mg g-1 utilizing the Langmuir isotherm model while the limit of detection (LOD) and relative standard deviation (RSD%) were established as 0.99 mu g L-1 and 3.7%, respectively. The developed method was utilized smoothly for the quantification of Au(iii) ions in mining wastewater, acid mine drainage (AMD), streams and seawater.
The present research investigates the removal of Brilliant Green (BG) and Remazol Brilliant Blue R (RBBR) dyes by an adsorption system utilizing drinking water treatment sludge (DWTS) as an adsorbent. It aims to contribute to sustainable treatment methods by evaluating waste sludge as a low-cost and environmentally friendly adsorbent. In the study, the significant parameters affecting the adsorption process were systematically investigated. During the experiments, the effects of factors such as initial pH of the solution, equilibrium time, adsorbent amount and initial dye concentration on the adsorption efficiency were evaluated. The obtained data were tested with Langmuir and Freundlich isotherm models and it was determined that adsorption occurred on both homogeneous and heterogeneous surfaces. The maximum adsorption capacity of DWTS was calculated as 100.0 mg g-1 and 38.9 mg g-1 for BG and RBBR, respectively. Kinetic analyses were performed to understand the dynamics of the adsorption process. Pseudo-first order and Pseudo-second order kinetic models were evaluated and it was noticed that the pseudo-second order model explained the adsorption data better. As a result, DWTS has been proven to be an effective adsorbent in the removal of BG and RBBR. The findings indicated that DWTS has significant potential for evaluation in advanced treatment processes in terms of environmental sustainability.
A novel and efficient adsorbent was prepared by modifying Fagus orientalis L. (beech) sawdust with H2SO4. The adsorption behavior of H2SO4-modified beech sawdust (SMBS) was investigated by batch experiments to offer a straightforward, inexpensive, and effective method for the retention of anionic and cationic model dyes, indigo carmine (IC) and methylene blue (MB), from wastewater. The experimental conditions were optimized by investigating the effects of the initial pH, initial concentrations of IC and MB dyes, dosage of SMBS, period of the contact, and the presence of salts in the aqueous media on the adsorptive performance of SMBS. The initial pH values of the aqueous solutions, from which IC and MB dyes will be removed, were optimized as 2.0 and 6.5 (natural), respectively. The optimum contact time for the adsorption of both dyes onto SMBS was determined to be 240 min. The mechanisms in the adsorption of IC and MB onto SMBS were investigated by evaluating the experimental data through different isotherm and kinetic models. The Langmuir isotherm model and pseudo-second order kinetic model performed well in explaining the mechanism of adsorption. Langmuir monolayer adsorption capacity of SMBS adsorbent was 38.85 mg g−1 for IC and 58.82 mg g−1 for MB. As a result, CMCP exhibited excellent performance in adsorbing organic pollutants, providing a low-cost and easily prepared alternative to other adsorbents found in the literature.
A new and cost-effective adsorbent material was developed by chemical modification of cucumber peels (CP) with a cationic surfactant, cetyltrimethylammonium bromide (CTAB). The adsorptive behavior of CTAB-modified cucumber peels (CMCP) was investigated in the retention of an organic pollutant (4-chlorophenol) and an inorganic pollutant (Cr(VI)) through batch experiments. The adsorbents were characterized by Fourier transform infrared spectroscopy (FTIR) analysis and scanning electron microscopy (SEM) technique. Influences of initial concentrations of both pollutants, dosage of CMCP, initial solution pH, contact time, and foreign ions were parameters used to specify the optimized conditions. Results of the experiments were evaluated by three kinetic models, namely pseudo-first-order, pseudo-second-order, and intraparticle diffusion models, to find out the dominant mechanisms in the retention of 4-chlorophenol and Cr(VI). Langmuir, Freundlich, and Dubinin–Radushkevich isotherm models were applied to the adsorption data to estimate the adsorption capacity of CMCP and to describe the interactions between the species. Langmuir isotherm model fitted the data well, and the maximum Cr(VI) and 4-chlorophenol adsorption capacities of CMCP were 84.03 mg g−1 and 107.5 mg g−1, respectively. Consequently, CMCP demonstrated outstanding performance in the adsorption of both inorganic and organic pollutants, offering a low-cost, easily prepared alternative to other adsorbents reported in the literature.
In the present research, a novel magnetic adsorbent was developed via the sol–gel method by coating CuFe2O4 nanoparticles on biochar sourced from brewed tea waste. The synthesized adsorbent was utilized for the removal of Ni(II) ions from aqueous media. The adsorption efficiency of Ni(II) ions was assessed under crucial experimental conditions such as initial solution pH, contact time, adsorbent dosage, and initial Ni(II) concentration. The adsorbent exhibited rapid adsorption kinetics, achieving equilibrium in approximately 15 min, and maintained high efficiency across a wide pH range. Adsorption experiments were conducted for Ni(II) solutions at their natural pH (5.6) to minimize chemical usage and enhance process simplicity. An impressive maximum adsorption capacity of 232.6 mg g−1 was recorded, outperforming many previously reported adsorbents. Furthermore, desorption studies demonstrated nearly 100% recovery of Ni(II) ions using 1.0 M HCl solution, indicating excellent regeneration potential of the adsorbent. Additionally, the prediction performance of an artificial neural network (ANN) model was evaluated to predict Ni(II) removal efficiency based on experimental variables, showing strong agreement with experimental data. Isotherm and kinetic models were also applied to the data to estimate the adsorption mechanisms. These findings demonstrate the promise of CuFe2O4-modified tea waste biochar for sustainable water treatment applications.
Presence of hazardous dyes in water cause considerable risks to the human health and environment due to their potential toxicity and ecological disruptions. Therefore, in the present research, to suggest an alternative method for the retention of toxic Azocarmine G (ACG) dye from aqueous media, natural and H 2 SO 4 -modified acacia sawdust were performed for the first time as low-cost and efficient adsorbents. Based on batch experiments, it was determined that the best conditions for the developed dye retention process were an initial pH of 2.0 and an equilibrium time of 240 min. Analysis of the data using both pseudo -first order and pseudo -second order kinetic models showed that the retention of ACG onto the adsorbents predominantly occurred through chemical adsorption. Langmuir, Freundlich, and Dubinin-Radushkevich isotherm models were employed to provide insights into the interaction between the adsorbate and adsorbent and the mechanism of the adsorption process. Maximum monolayer adsorption capacities of natural and H 2 SO 4 -modified acacia sawdust were determined as 28.01 and 64.90 mg g -1 , respectively by Langmuir isotherm model. Results of the study clearly indicated that the modification of acacia sawdust with H 2 SO 4 leads to a substantial increase in the adsorption performance of anionic dyes.
A facile and sensitive method predicated on carrier element free coprecipitation (CEFC) using 2-(2-(2-(4-bromobenzyl)-1H-benzo[d]imidazole-1-yl)acetyl)-N-ethylhydrazine-1-carbothioamide (BIMANEC) is reported for trace determination of Cu(II) and Cd(II) in vegetables and water. BIMANEC was used for the first time for the quantitative determination of these trace heavy metals. Flame atomic absorption spectrometer (FAAS) was used for quantitation. The preconcentration conditions were optimized with respect to pH (8.0), BIMANEC mass (4.0 mg), volume of sample (100 mL), standing time (5 min), and centrifugation time and rate (3 min and 2500 rpm). The influence of potentially interfering ions was scrutinized for the recovery of analyte ions. Under the optimum conditions, the limits of detection (LODs) were 0.51 and 2.28 mu g L-1 for Cu(II) and Cd(II), respectively. The relative standard deviations were < 5% for both. The recoveries from the spiked vegetable samples were from 94.9 to 102.8% and from the spiked water samples between 93.2 and 101.6%. Consequently the developed new, facile, rapid, and highly efficient CEFC process was employed for the trace determination of Cu(II) and Cd(II).
ABSTRACT The coating of magnetic Fe3O4 Alnus glutinosa sawdust biochar with SiO2 and further functionalising by cetyltrimethyl ammonium bromide (CTAB), a cationic surfactant, was described for the first time in the current paper. The magnetic Fe3O4 Alnus glutinosa sawdust biochar/SiO2/CTAB(MAGBC/SiO2/CTAB) was implemented to separate and preconcentrate the Cu2+, Cd2+, and Pb2+ions efficiently in waters and a number of fruit samples by solid-phase extraction (SPE) method. Adsorbent characterisation was realised by fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). Fundamental factors affecting the extraction yield of the analyte ions including solution pH, adsorbent amount, sample volume and desorption contact time were fully researched and optimised as 8.0, 0.25 g, 500 mL and 60 min, respectively, and the eluent was specified as 5.0 mL of 0.1 M of HCl solution. The adsorption equilibrium eventuated after 15 min of contact time and it was noticed that the chemisorption mechanism was dominant upon the analyte ions adsorption. The limits of detection (LOD) were calculated as 0.24, 0.62 and 1.55 µg L−1 and the limits of quantitation (LOQ) were determined as 0.81, 2.08, and 5.17 µg L−1 for Cu2+, Cd2+, and Pb2+ ions, respectively. The relative recoveries (RR%) were in the ranges of 93.3–103.4%, 92.5–102.8%, and 91.8–101.9% for Cu2+, Cd2+, and Pb2+ ions, respectively, while the relative standard deviations (RSD%) were obtained lower than 4.0% (n = 10) by applying the method at optimised conditions. The maximum adsorption capacities of MAGBC/SiO2/CTAB were obtained as 123.7, 80.0 and 118.5 mg g−1for Cu2+, Cd2+, and Pb2+ions, respectively. Consequently, the developed new, simple, rapid, sensitive, and economical SPE method based on MAGBC/SiO2/CTAB was successfully implemented to waters and some of the fruit samples to determine the Cu2+, Cd2+, and Pb2+ions simultaneously.
The aim of the present research is to develop a new, fast, and easily applicable adsorption method for the removal of hazardous Cr(VI) and Cu(II) ions from the polluted industrial wastewater by using Racomitrium ericoides (Brid.) Brid. (REB), a type of moss. Although there are studies in the literature in which different moss species were used for the removal of heavy metals (HMs), REB was used for the first time in this study. Adsorption experiments were carried out through a batch system. The impact of significant experimental parameters showed that the optimum values of initial pH were 2.0 for Cr(VI) retention and 5.0 for Cu(II), and 360 min was selected as the optimum contact time for both HMs. An artificial neural network (ANN) model was applied to create a predictive model for the uptake efficiency of HMs. Adsorption kinetics of Cr(VI) and Cu(II) ions followed the pseudo-second order model. The maximum adsorption capacities of REB identified through the Langmuir model were 41.2 mg g−1 for Cr(VI) and 22.7 mg g−1 for Cu(II) ions. The results of the study demonstrated that REB can be utilized as an abundant, low-cost, and effective adsorbent in removal of HMs from aqueous solutions.
Elimination of the matrix effect is a major challenge in developing a method for the quantification of heavy metals (HMs) in water samples. In this regard, the current research describes the simultaneous analyses of Cu(II), Cd(II), and Ni(II) ions in water matrices through flame atomic absorption spectrophotometry (FAAS) after preconcentration with carrier element-free co-precipitation (CEFC) technique by the help of an organic co-precipitant, 3-{[5-(4-Chlorobenzyl)-3-(4-chlorophenyl)-1H-1,2,4-triazol-1-yl]-methyl}-4-[2,4-(dichlorobenzylidene)amino]-1H-1,2,4-triazole-5(4H)-thione (CCMBATT). Based on our literature research, CCMBATT was employed for the first time in this study as an organic co-precipitant for the preconcentration of HMs. Factors such as solution pH, concentration of co-precipitant, sample volume, standing time, centrifugation rate, and time were thoroughly examined and optimized to achieve the highest efficiency in terms of HM recovery. The limits of detection (LODs) (with 10 number of tests) of 0.54, 0.34, and 1.95 μg L-1 and the relative standard deviations (RSD %) of 2.1, 3.3, and 3.0 were determined for Cu(II), Cd(II) and Ni(II) ions, respectively. Recovery results of HMs for the spiked samples were in the range of 92.8-101.0%, demonstrating the trueness of the method and its applicability to the water samples matrix.
Natural and H2SO4-modified plane (Platanus orientalis L.) sawdust were used for the adsorptive removal of cationic methylene blue (MB) and anionic indigo carmine (IC) dyes from aqueous media to suggest a new and cost-effective method for wastewater treatment applications. The influences of initial pH values, concentrations of MB and IC, period of contact, dosages of the natural and modified plane sawdust, and the presence of foreign ions on the adsorption of dyes were investigated in the experimental studies to describe the best conditions of the most efficient adsorption processes. Initial pH values were optimized to be between 6.0-8.0 for MB and 2.0 for IC. Experimentations of Boehm titration, FTIR analysis, pHpzc value, and moisture content determinations were utilized to characterize the natural and modified sawdust materials. Langmuir, Freundlich, and Dubinin-Radushkevich isotherm models were used to evaluate the sorption mechanism. Maximum adsorption capacities of natural plane sawdust (NPS) and H2SO4-modified plane sawdust (MPS) calculated from the Langmuir isotherm model were 55.56 and 38.46 mg g-1 in MB adsorption, and 55.82 and 55.55 mg g-1 in IC adsorption, respectively. Results showed that the natural and H2SO4-modified plane sawdust serve as low-cost and efficient materials in the adsorptive removal of MB and IC dyes for industrial wastewater treatment applications.
Natural mulberry leaves and carboxylic acid-modified mulberry (Morus alba L.) leaves were used for the first time to scrutinize the effects of modification on the retention efficiency of an anionic dye (Remazol Brilliant Blue R (RBBR)) from aqueous solutions to suggest an economical and promising adsorbent for the treatment of dye-contaminated water. The characterization of the adsorbents was accomplished through common techniques including SEM, FTIR, and pHpzc determination. Several parameters studied in batch experiments pointed out that the initial pH of 2.0 and the contact time of 240 min were optimum conditions for all the developed RBBR uptake processes. An artificial neural network (ANN) model was applied to formulate a forecast model for the uptake efficiency of RBBR. The experimental data were assessed by different kinetic and isotherm models to explain the mechanism of the developed processes in more detail. Maximum monolayer adsorption capacities of natural mulberry leaves and acetic acid-, citric acid-, and oxalic acid-modified mulberry leaves were determined as 64.5, 95.2, 84.8, and 91.7 mg g-1, respectively, by the Langmuir isotherm model. These results demonstrated that the modification with carboxylic acids significantly increases the anionic dye adsorption capacity of the mulberry leaves.