Removal Of Industrial Dyes Research Articles

Simulation and modeling of methylene blue dye removal by an agri-food waste (Peanut shells)

Our study explores the potential of utilizing peanut shells, an abundant and low-cost food waste, as a natural adsorbent for the removal of industrial dyes, specifically methylene blue. We conducted a detailed investigation of the adsorption process, which revealed that it conforms to both Langmuir and Freundlich isotherms, indicating the ability of peanut shells to adsorb methylene blue effectively. To optimize the adsorption yield, we employed a Box-Behnken experimental design. This approach allowed us to assess the impact of several key factors, including the mass of the adsorbent, dye concentration, pH, temperature, stirring rate, and the ionic strength of salts in the solution. The mathematical model and simulation of the adsorption process helped us identify the best conditions for maximizing the dye removal. Our experiments resulted in a maximum adsorption efficiency of 97%, achieved under optimal conditions: 1.5 g of adsorbent, a methylene blue concentration of 40 mg/L, pH 11, temperature of 65°C, 0 mg/L ionic strength, and a stirring rate of 165 rpm. These findings suggest that peanut shells are a viable, eco-friendly alternative for dye removal, offering a sustainable solution for wastewater treatment and contributing to waste reduction.

Assessment of carbonized himalayan chir pine biomass as an eco-friendly adsorbent for effective removal of industrial dyes

This study investigates the use of carbonized Himalayan Chir Pine Biomass, known as Chir Pine Activated Carbon (CPAC), as an eco-friendly and cost-effective adsorbent for efficient industrial dye removal, with a focus on environmental sustainability. By applying different additive treatments, four adsorbents (C1, C2, C3, and C4) were formulated. CPAC was synthesized through pyrolysis and characterized using various analytical techniques including FE-SEM, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and differential scanning calorimetry (DSC). The adsorption capacity of CPAC was evaluated using Malachite Green (MG) dye as a model contaminant. FE-SEM images revealed high porosity (~ 10 µm) and a high surface area (119.886 m2/g) as confirmed by BET testing. CPAC effectively removed MG dye within 30 min at a solution pH of 7. Langmuir and Freundlich isotherm models indicated both monolayer and multilayer adsorption, while kinetic models suggested chemisorption. The regeneration efficiency was assessed using 0.1 N HCl over five consecutive cycles, with C4 demonstrating a high regeneration tendency of 85% and only a 9% reduction in adsorption ability after the fifth cycle. The developed CPAC shows excellent potential for use in the textile, paper, and leather industries for industrial dye adsorption, contributing to the protection of aquatic ecosystems. Additionally, CPAC can be utilized in other water and air purification applications.

Photocatalytic Removal of Industrial Dye Including Cationic Compound from Aqueous Solution Using ZIF-Cu(im)2

Photocatalytic Removal of Industrial Dye Including Cationic Compound from Aqueous Solution Using ZIF-Cu(im)2

One-pot growth and characterization of α-Fe2O3/β-FeOOH micro-nanosystem for industrial dye removal

A micro-nanosystem of α-Fe2O3/β-FeOOH was developed for the first time using a one-pot hydrothermal method. The synthesis mechanism of the simultaneous development of micro-sized α-Fe2O3 and nano-sized β-FeOOH is discussed. The structural properties studied via X-ray diffraction (XRD) revealed the presence of both phases, whereas the FESEM study confirms that α-Fe2O3 and β-FeOOH are of microdisc and nanohusk type, respectively. Considering the two different shapes and sizes of particles in a micro-nanosystem, α-Fe2O3/β-FeOOH was used to remove rhodamine B dye. The hydrogen bonding between the adsorbent and the RhB dye influences the binding properties. The mixed-shaped iron-based particles have provided maximum adsorbing sites which have strengthened the bonding between the adsorbent and adsorbate. The FTIR study was used to confirm the binding of RhB dye with the micro-nanosystems. Adsorption capacity and removal efficiency for α-Fe2O3/β-FeOOH micro-nanosystem adsorbent were found to be 727 mg g−1 and 91 % respectively. The binding mechanism along with the adsorption isotherm and adsorption kinetic study, has been discussed. The adsorption isotherm study confirms that the adsorption process followed the Freundlich isotherm model. The adsorption kinetic study suggested the well-fitting of pseudo-first-order kinetics and the Elovich model with the adsorption process. The reusability study of the micro-nanosystem confirms that the micro-nano system can retain the highest removal efficiency up to 4th cycle. Further, the fabricated micro-nanosystem was applied for the removal of RhB dye from the real water samples, collected from different sources.

Synergistic removal of toxic anionic reactive red dye Me4BL (RRME4BL) from aqueous media using chemically synthesised nano-adsorbents (ZnO, CuO, NiO and CoO); equilibrium, kinetics and thermodynamic studies

ABSTRACT This study explores the efficient removal of the synthetic anionic dye-reactive red Me4BL (RRMe4BL) from an aqueous medium which is a significant contributor to environmental pollution. The present study investigates the synthesis of zinc oxide, nickel oxide, cobalt oxide and copper oxide nano adsorbents (ZnO (II), NiO (II), CoO (II), CuO (II)) through the co-precipitation method and their effectiveness in eliminating the reactive red dye Me4BL(RRMe4BL). Maximum adsorption capacities were achieved at pH 2 for ZnO (96.1 mg/g), NiO (86.9 mg/g), CoO (93.4 mg/g) and at pH 6 for CuO (76.3 mg/g) under a 0.05 g/50 mL nano-adsorbent dose, 50 mg/L dye initial concentration and 25°C T and 90 min of contact time. The fitness of the pseudo-2nd-order model explained the kinetics, while Langmuir and Temkin adsorption isotherm highlighted the efficiency of the dye adsorption. Thermodynamic studies revealed the spontaneous and exothermic nature of adsorption. The influence of electrolytes, surfactants and desorption was also analysed. Characterisation of the nanoparticles was done through SEM, XRD and FTIR which revealed the morphology and functional groups of nano-adsorbents. The adsorption method used for eliminating this anionic red dye shows several benefits, including affordability, simplicity of use and the presence of intelligent adsorbents for environment-friendly removal of industrial dyes from wastewater.

Valorization of Parthenium hysterophorus weed into biochar for adsorptive removal of industrial dyes from multi-pollutant aqueous systems

Valorization of Parthenium hysterophorus weed into biochar for adsorptive removal of industrial dyes from multi-pollutant aqueous systems

Natural bamboo powder and coffee ground as low-cost green adsorbents for the removal of rhodamine B and their recycling performance

Bamboo and coffee, which are abundant and inexpensive, have been used as green adsorbents for the adsorption of industrial dye rhodamine B (RB). Bamboo and coffee are natural sources of cellulose, hemicellulose, and lignin, making them promising green materials for industrial dye removal. The effects of various adsorption conditions, such as contact time, temperature, dose of bamboo powder (BP), coffee ground (CG), initial concentration of RB, and pH values of RB solution, were measured. Consequently, the kinetics of RB adsorption onto bamboo and coffee was in accordance with the pseudo-second-order model, with an activation energy of 29.51 kJ mol−1 for bamboo and 27.46 kJ mol−1 for coffee. The Langmuir model is well fitted to the whole adsorption period at different temperatures, in which the increase in the tested temperature has improved the adsorption capacity (i.e., BP: 6.76 mg g−1/30 °C, 6.96 mg g−1/40 °C, 7.64 mg g−1/50 °C and CG: 6.53 mg g−1/30 °C, 6.80 mg g−1/40 °C, 7.51 mg g−1/50 °C). Moreover, the spontaneous nature of the adsorption was based on the negative Gibbs free energy values obtained (i.e., from − 11.09 to − 14.30 kJ mol−1 [BP] and from − 10.34 to − 13.07 kJ mol−1 [CG]). These revealed that RB adsorption occurred at physical and chemical adsorption states. In addition, the recycling capability of adsorbents was determined in five cycles. Therefore, these materials are promising candidates for low-cost adsorbents.

Cobalt modified enhancement in photocatalytic efficiency of SnO2 nanoparticles for removal of industrial dyes

Cobalt modified enhancement in photocatalytic efficiency of SnO2 nanoparticles for removal of industrial dyes

Synergetic Adsorption‐Catalysis in Potassium Oxide Modified High‐Entropy Relaxor Ferroelectrics for Efficient Dye Removal Strategy

Water scarcity caused by extreme weather events has become a global issue, leading to the necessity of wastewater recycling. Developing new materials with fast pollutant removal efficiency has become a research focus in related fields for producing clean water resources quickly and stably from wastewater. Herein, a relaxor ferroelectric type of piezoelectric high entropy perovskites, Pb(Mg,Nb,Hf,Zr,Ti)O3 (PMNHZT), is used and prepared for industrial dye removal. The synthesized PMNHZT exhibits high dark adsorption of the methylene blue dye (removal efficiency of ≈60% in 30 min) and further catalytic dye degradation (removal efficiency of ≈80–90% in 30 min) through light illumination, sonication, or a combination of both. In the dark adsorption process, K2O compounds from the synthesized environment attached to the surface of PMNHZT play a significant role in the remarkable dark adsorption by promoting a large specific surface area and more negative surface potential. Furthermore, a self‐decomposition of dye into smaller fragments by PMNHZT is also observed during dark adsorption. The piezocatalysis mechanism dominates the dye degradation process in catalytic experiments, where hydroxyl radicals are the main reactive species. Herein, a promising adsorbent and catalyst is disclosed using high‐entropy perovskites for efficient wastewater treatment.

Development of a novel in-situ aluminum/carbon composite from olive mill wastewater for the selective adsorption and separation of malachite green and acid yellow 61

In this study, an aluminum/carbon composite was developed from olive mill wastewater (OMWW) and successfully applied in the removal/separation of malachite green (MG) and acid yellow 61 (AY61) and in the treatment of a real discharge from a denim dye bath. The optimized composite (0.5% Al) is microporous, has a specific surface area of 1269 m2.g−1, rich in anionic sites, has an adsorption capacity of 1063 mg.g−1 and exhibited efficient separation of AY61/MG. Thermodynamic results showed physical, endothermic and disordered adsorption. The substrates were attached to the surface by electrostatic, hydrogen and π- π interactions through the contribution of multiple sites in parallel and non-parallel orientations. The composite can be used repeatedly without significantly losing its performance. This study, presents an exploitation of agricultural liquid waste to develop carbon composites for industrial dye removal and separation, creating new economic opportunities for farmers and rural communities.

Adsorption and Removal of Industrial Dyes by Water-Stabilized Aluminum-Based Metal–Organic Frameworks

Pollution of water resources by industrial dyes can threaten environmental safety and human health even at low concentrations. We proposed the adsorption removal of a typical azo dye, Congo red (CR), by CAU-23, an aluminum-based metal–organic framework (MOF). To characterize CAU-23, X-ray diffraction (XRD), Fourier transform infrared (FT-IR), and thermogravimetry (TG) were employed. An investigation of the impact of the material on the adsorption kinetics, thermodynamics, and ionic strength of CR was conducted. The results demonstrated that the quasi-second-order kinetic model and Langmuir isotherm were in harmony with our experimental sorption data. Additionally, thermodynamic parameters of adsorption such as enthalpy and free energy were evaluated. Nanoporous CAU-23 with excellent water stability and suitable pore size is well suited for capturing CR molecules. Importantly, through a comprehensive investigation of experimental and theoretical studies, CAU-23 forms π–π interactions and electrostatic attraction with CR molecules, characteristics that promote CAU-23 as one of the most promising adsorbents for the elimination of CR from water.

Superior adsorption and removal of industrial dye from aqueous solution via magnetic silver metal-organic framework nanocomposite

ABSTRACT The indirect emission had a negative influence on the ecosystem of enormous amounts of harmful dyes into water. Fe3O4@Ag-MOF was successfully fabricated to capture Gentine violet (GV)) as a model example of cationic dye from their aqueous solutions was evaluated in this search as a method to eliminate dyes from water contaminants. FTIR, XPS, BET, TGA, SEM, TEM, and XRD have all been used to study this adsorbent in order to determine its structural and chemical characteristics as well as to interpret its binding mechanisms. According to the results of the characterization, the synthesized composite had a size about 45 nm, a surface area of 856.06 m2/g, and considerable magnetic characteristics (66.2 emug−1). Consequently, we created mesoporous surfaces that had a strong ability to interface and absorb GV dye. It is possible to use the pseudo-second order rate equation to characterize the kinetic profile., while the Langmuir equation fits isotherm models. At pH 9, maximum sorption capacities can reach 1.68 mmol.g−1. Additionally, the investigations of temperature profiles indicated the endothermic process and Thermodynamic parameters were discovered as, ΔG°, ΔH° and ΔS° The synthesized adsorbent had an interestingly high reusability of > 92 percent up to the sixth cycle. These findings revealed that a mixture of electrostatic interactions, π-π stacking, hydrogen bonds, and pore filling were involved in the GV adsorption mechanism. Fe3O4@Ag-MOF was successful in demonstrating its effectiveness as a point-of-use colour collection candidate from actual dyeing effluents.

Experimental study and modelling of an azo colourant dynamic adsorption onto functional cross‐linked chitosan/ceramic particles in a fixed bed column

AbstractThe use of azo dyes in industrial activities generates a large volume of contaminated wastewater; these pollutants in water bodies affect aquatic biota and human health. A functional biocomposite sorbent material was synthesized using cross‐linked chitosan with oxalic acid that forms a coating on alumina ceramic particles (AOCh). The removal of Reactive Red 195, a reactive azo dye, using a fixed‐bed adsorption column filled with this material was tested. AOCh was physico‐chemically characterized by Fourier transform infrared spectroscopy–total attenuated reflection (FTIR‐ATR), scanning electron microscopy–energy dispersion spectrometry X‐ray (SEM‐EDS), X‐ray diffraction (XDR), thermo‐gravimetric analysis (TGA), and Z‐potential. The dynamic adsorption performance was analyzed from experimental breakthrough curves obtained in fixed‐bed columns by modifying different operating conditions (bed depth, volumetric flow rate, and dye inlet concentration). Equilibrium adsorption isotherms were determined under dynamic conditions and compared with batch results. The maximum adsorption capacity of the dynamic equilibrium isotherm obtained from the continuous assays was 331 mg/g; this value was the highest in comparison to other tested materials reported in the literature. Different dynamic adsorption models were applied to fit experimental data, including Thomas, Bohart–Admas, Yoon–Nelson, logistic general model, bed depth surface time (BDST), and modified dose response (Yan) models. A critical analysis of these equations was presented, showing the equivalences and the relationship among the coefficients. The Yan model achieved the highest level of agreement between the experimental and predicted values of the breakthrough curves. The use of this model enables scaling‐up the industrial process for dye removal. The present work proposed a novel biosorbent material and contributes to the analysis of industrial dye removal under dynamic conditions.

Biogenic synthesis, molecular docking, biomedical and environmental applications of multifunctional CuO nanoparticles mediated Phragmites australis

The demand for metal nanoparticles is increasing with the widening application areas while causing environmental impact including pollution, toxic byproduct generation and depletion of natural resources. Incorporating natural materials in nanoparticle synthesis can contribute toward environmental sustainability. This paper is concerned with the biogenic synthesis of copper oxide nanoparticles (CuONPs) mediated by the plant species Phragmites australis. UV–vis, FT-IR, TEM and SEM studies were used to characterize the obtained CuONPs. The synthesized nanoparticles' antibacterial efficacy against Escherichia coli and Staphylococcus aureus was assessed. The CuONPs' reducing power, total phenolic component content, and flavonoid content were all calculated. Additionally, the dye removal abilities of copper oxide nanoparticles using Brilliant Blue R-250 were studied. The CuONP synthesis was assessed morphological by change of color and in the UV–vis analysis by the SPR band around 320 and 360 nm. FT-IR was used to monitor the functional groups present in the synthesized CuONPs. The obtained CuONPs were spherical and between 70 and 142 nm in size, according to the SEM data and TEM analyses were in accordance with SEM results. Using disk diffusion, the CuONPs demonstrated substantial antibacterial efficacy against S. aureus and E. coli, with inhibition zones of 18.5 ± 0.8 and 12.7 ± 0.6 mm, respectively. The MBC and MIC values were 62.5 μg/mL against S. aureus and 125 μg/mL against E. coli. The antioxidant abilities of P. australis and CuONPs were also confirmed. The CuONP solution's total phenolic substance content was 9.44 μg of pyrocathecol equivalent per milligram of nanoparticle, and its total flavonoid content was 16.24 μg of catechin equivalent per milligram of nanoparticle. Additionally, the synthesized CuONPs were found to be well effective on industrial dye removal by demonstrating high decolorization of 98 %. Also, the antibacterial activity of CuONPs was investigated through the interactions with S. aureus FtsZ, dihydropteroate synthase and thymidylate kinase. In silico molecular docking analysis was applied in the confirmation of the binding sites and interactions of active sites. CuONP showed −9.067, −8,048, and −7.349 kcal/mol of binding energies in molecular docking analysis of FtsZ, dihydropteroate synthase and thymidylate kinase proteins respectively. The results of this study suggested the antimicrobial, antioxidant and decolorative effect of synthesized CuONPs that can be apply in multiple areas of R&D and industry.

Synthesis of Ce–Ni/sepiolite with excellent adsorption and catalytic oxidation performance toward dyes

A novel and highly efficient wastewater treatment process for the removal of industrial dyes was proposed in this study.

Environmental applications of flame synthesized CuO nanoparticles through removal of Congo Red dye

The Copper oxide (CuO) transition metal oxide nanoparticles (NPs) synthesized by simple, fast and commercially viable comfortably slight modified flame pyrolysis method. The CuO NPs were synthesized by direct burning of ethanolic copper chloride solution. The prepared CuO NPs were characterized for phase and crystallinity by X–ray Diffraction [XRD] and Fourier Transform Infrared [FT–IR] Spectroscopy, estimation of morphology was done by Field Emission Transmission Electron Microscopy [FE–SEM], average particles size of prepared CuO NPs estimated by High Resolution Transmission Electron Microscopy [HR - TEM] as well purity ensured by Energy Dispersive X–Ray Spectroscopy [EDS]. UV–vis absorption spectroscopy done for adsorption of aqueous Congo Red (CR) dye of flame synthesized CuO NPs. The structural, elemental and morphological characterization emphasised the synthesized CuO NPs are crystalline, pure and exhibited monoclinic structure with spherical morphology. The environmental applications of these flame synthesized CuO NPs were also evaluated by using adsorption of Congo Red (CR) dye and temperature effect on dye adsorption were also verified. HR-TEM revealed the average particles size of around 30 nm with fringe spacing of 2.788 Å and 2.377 Å, which corresponds to (110) and (200) planes of monoclinic phase of CuO NPs. The synthesized CuO NPs exhibited optical bandgap of 2.93 eV. The synthesized NPs showed high dye removal capacity up to 99.90% for the aqueous solution of Congo Red azo dye. These CuO NPs may emerge as the best catalytic adsorption alternative for the removal of industrial dyes, heavy metals and waste water treatment.

Cobalt oxide nanoparticles by flame pyrolysis for efficient removal of mixed dyes

The cobalt oxide nanoparticles were prepared by low cost, gram scalable and environment friendly flame pyrolysis method by directly burning ethanolic solution of cobalt chloride. The cobalt oxide formation, functional group identification, morphology and particles size of as-synthesized nanoparticles were carried out using routine techniques viz. XRD, FTIR, FE-SEM, HR-TEM, Raman Spectroscopy and Vibrating Sample Magnetometer (VSM) analysis. The XRD pattern ensured the formation of Cobalt Oxide nanoparticles (CoO NPs). It also emphasized that synthesized CoO NPs are pure, crystalline and single phased. EDS ensured the purity of CoO NPs which contained only cobalt and oxygen. FE-SEM exhibited spherical morphology with particles size of around 30 nm aligned with Debye–Scherrer’s calculated average crystallite size of 20 nm. The optical direct band gap of CoO NPs was estimated using Kubelka - Munk function to be 2.97 eV. The magnetic behavior examined at room temperature by VSM confirmed the formation of CoO NPs with weak ferromagnetic nature. The CoO NPs were utilized successfully for the removal of mixed dye solutions. The CoO NPs showed excellent efficiency for the removal of mixture of hazardous dyes from the aqueous solutions. This makes CoO NPs valuable for removal of industrial dyes and colorants for the waste water treatment processes.

Modification of activated carbon-based adsorbent for removal of industrial dyes and heavy metals: A review

The resources of water are contaminated by discharging of various pollutants from sources including industrial and domestic zones. A variety of physical, chemical, and biological processes are implemented for treating pollutants. Adsorption is the most accustomed process due to its high efficiency, simple procedure, and cost-effectiveness. Adsorption is widely used for removing various pollutants from wastewater. This review focused on physical and chemical modified adsorption systems indicates the improvement in adsorption of industrial dyes and heavy metals from wastewater. Chemical modifications, comprise with the acid, base, and impregnation of metal ions, are broadly studied due to availability of reagents, easy in modification, and adjusting surface functional groups. Different activating agents are used to introduce the different surface functional groups, which also depend on the type of water to be treated. Literature shows the high adsorption ability of industrial dyes and heavy metals towards chemically modified activated carbon, especially with LiOH, KOH and H2SO4 which shows the improvement in oxygenated functional groups. The adsorption capacity increases up to 40 % after modification within an activation temperature of 75 to 900 ℃, and 60 to 240 min of activation time is beneficial and depends on the adsorbents used. The physical modification by microwave heating provides a quick thermal reaction with homogeneous structure from inside out and equal distribution of pore structure and texture. The modification cost also plays an essential role while selecting adsorbents. The physical and chemical modification significantly improves the pore volume and various functional groups, which are quick low-cost treatment processes. The physical and chemical activation cost with LiOH, KOH, and H2SO4 reagents found in USD 1.72 to 2.89 per kg of adsorbent is suitable for large-scale models.

Influence of Some Preparation Parameters on The Efficiency of Activated Carbons Prepared from Teak Wood Shavings (Tectona Grandis) and Coconut Shells (Cocos Nucifera) for The Treatment of Industrial Wastewater

In this work, we valorized two wastes of plant origin in activated carbon (AC) by chemical activation, with a view to their use for the elimination of industrial dyes and artisanal dyeing simulated by methylene blue and iodine in the water. These are coconut shells (Coco nucifera) and teak wood chips (Tectona grandis). For the preparation of activated carbon based on coconut residues, the chemical activation was carried out by citric acid extracts of lemon juice (Citrus aurantiifolia) and then compared to that carried out with phosphoric acid and hydroxide of potassium. For the preparation of activated carbon from the teak residue, the activating agent used is potassium hydroxide. The results obtained show that activated carbon based on the coconut are microporous and mesoporous with an iodine number between 338.9 and 487.9 mg/g, a methylene blue number between 369.2 and 447.2 mg/g and a more pronounced post-treatment residual acidity for phosphoric acid than with lemon juice. The test conditions (the impregnation ratio, the duration, and the carbonization temperature) made it possible to prepare six activated carbons from the teak residue. The carbonization time does not have a significant effect on the adsorption efficiency although it does have a considerable effect on the carbonization efficiency. The adsorption kinetics of methylene blue on these materials is second order and the adsorption isotherm is more of the Langmuir type than that of the Freundlich model; this isotherm is characteristic of a wide distribution of microporosity and a well-developed mesoporosity. These activated carbons can therefore be used in the treatment of wastewater, in particular for the removal of industrial dyes and artisanal dyeing.

Industrial dye removal from tannery wastewater by using biochar produced from tannery fleshing waste: a road to circular economy

In this study, the capacity of biochars, derived from the pyrolysis of tannery fleshing waste (TFW) at 400 °C; 500 °C and 600 °C, in removal of red dye Sella Fast Red (SFR) from aqueous solutions and tannery wastewater was investigated under various experimental conditions in batch mode. Results show that for all applied biochars, the removed kinetics data were well fitted by the pseudo-second-order model, and the equilibrium state was obtained after 240 min of contact time. For an aqueous pH of 6 and a red dye concentration of 75 mg·L -1 , the removed amounts increased from 26 mg·g -1 to 39.86 mg·g -1 when the used pyrolysis temperature was increased from 400 °C to 600 °C. Moreover, SFR adsorption data at equilibrium were well fitted by Langmuir model suggesting a probable monolayer adsorption process with a maximal removal capacity of 62.7 mg·g -1 for BTFW-600 °C. The thermodynamic study demonstrated that SFR adsorption was endothermic for the three tested biochars. Desorption experiments with distilled water proved that SFR was significantly desorbed from the tested biochars, which offers possible reusability. On the other hand, BTFW-600 °C has demonstrated an important ability in removing SFR from real wastewater since only one dosage of 15 g·L -1 was enough to ensure more than 97% of dye removal. According to pH ZC and FTIR analysis, the possible mechanism toward SFR dye removal was attributed to electrostatic interactions that occurred between biochar and functional groups of SFR. This work could provide guidance for the value-added utilization of tannery solid waste and a practical way to remove dyes from tannery wastewater.