Leather Processing Research Articles

Proposal of an environmental performance index to assess leather-manufacturing companies

Despite the global economic and environmental importance of the leather industry, the specialized literature still presents an important gap in analyzing the environmental performance of the leather manufacturing process from the waste generated. This paper aims to propose an unprecedented index (Index of Leather Manufacturing- ILM) to evaluate the environmental performance of leather manufacturing processes. The development of the index combines Life Cycle Assessment (LCA) and a Multicriteria Decision Method (MCDM) and is oriented to consider the impact of waste on environmental health. Its estimate is based on: the calculation of the environmental potential impact of the waste; the waste quantity produced by the company over a given period; the relative geographic coverage that each waste can achieve; the assessment of the appropriateness of the disposal of waste generated by the firm. The proposed index was tested on a large Brazilian leather manufacturer. The results showed that the waste management in the company is not perfect but is well rated, and residues with the greatest environmental impact are: wetblue shavings, wetblue sawdust, and gaseous emissions from beam house operation.

Application of response surface methodology to optimize chromium (VI) removal from aqueous solution using pre‐treated sawdust

AbstractIncreased chromium usage in industrial applications as chromium III and chromium VI, include metal plating, steel alloys, leather processing, medical applications, and chromium dyeing operations, has resulted in water pollution by Cr (VI) ions, which being toxic and carcinogenic has developed into significant environmental and health problems. The purpose of this research is to remove Cr (VI) ions from synthetic wastewater utilising modified sawdust as an inexpensive adsorbent. Two modified sawdust samples were produced, one using sodium hydroxide and one using sulfuric acid. The experimentation, based on several batch systems, has been undertaken at 25–65°C with 0.5–1.5 g/L sawdust dosage. These conditions were applied to remove Cr (VI) ions at concentrations of 1–6 ppm at pH values from 3 to 10. The results have shown that adsorption onto sawdust followed an intraparticle diffusion mechanism with various rate parameters from 0.65 to 5.24 mg g−1 min, for treated and untreated sawdust. The distribution coefficient , enthalpy , thermodynamic standard free energy , and entropy were determined from a number of temperature studies. Kinetic studies showed that the pseudo‐second order model gave the optimum correlation to the experimental results. The Freundlich and Langmuir isotherms were applied to analyse the experimental equilibrium results. The optimised conditions for the adsorption process were obtained using the D‐optimal design method, and the maximum removal percentage of 100%, was determined at pH = 3, T = 25°C, adsorbent dosage = 1.5 g/L, and an initial Cr (VI) concentration = 5.72 ppm.

Impact of tannery wastes on anaerobic co-digestion: enhancing biogas production and process efficiency

The study investigates the potential of anaerobic co-digestion (AcoD) as a sustainable solution for managing putrescible organic waste generated by leather processing. Three experiments were conducted to assess the impact of various tannery wastes, pretreatment methods, and waste combinations on methane production. Experiment 1 demonstrated that co-digesting tannery wastewater primary sludge (TWPS) and fleshings significantly increased methane yield compared to digesting TWPS alone, though the addition of chromium- and vegetable-tanned leather wastes decreased yield. Experiment 2 explored TWPS pretreatment methods and found that ultrasonic pretreatment increased soluble chemical oxygen demand (SCOD) but did not significantly improve methane yield, suggesting that pretreatment may not be necessary. Experiment 3 revealed that increasing the proportion of fleshings to TWPS resulted in higher methane yield, ranging from 226.52 mL/gVS with 6% fleshings to 395.71 mL/gVS and 538.34 mL/gVS with 12% and 20% of fleshings, respectively. Additionally, this increase in fleshings also led to a reduction in digester volume. These findings highlight the importance of AcoD in addressing both environmental and economic challenges in the leather industry.Graphical

An Eco-Friendly Approach to Preserve Goatskins Using Tamarindus Indica Leaf

Hides and skins, the main raw materials for leather industries, are traditionally preserved with sodium chloride (NaCl). Due to the excessive use of salt (around 40 to 50% w/w) in the curing process, total dissolved solids (TDS), and salinity are produced in large quantities by the soaking effluent during the leather processing. To address the resulting environmental threat from the tanneries and replace traditional curing, plant-based curing is a cutting-edge green technology. In this study, Tamarindus indica leaves were used as a combination of 5% powder + 10% salt and 10% paste + 10% salt to preserve goat skin for 28 days. The organoleptic characteristics, hydrothermal stability, moisture content, nitrogen content, and bacterial load were periodically monitored. After curing, the goatskin was processed into leather, the environmental impact of the wastewater was evaluated, and its physical and fibre strength was assessed. The TDS value, chloride content, biochemical oxygen demand, and chemical oxygen demand were reduced up to 65.62%, 69.38%, 31.08%, and 27.06% respectively. The prepared shoe-upper leather exhibited equivalent physical properties compared to the control. Scanning electron microscopy (SEM) image ensured the conformity of the fibre structure of the experimental leather with control. A significant correlation was seen among the skin preservation efficiency parameters, while the strongest correlation was (r = -0.996, p<0.001) between moisture content and shrinkage temperature. Therefore, T. indica leaves powder as well as paste could be an effective curing agent by reducing the use of salt in leather industries.

Ultrasound-Assisted Extraction, Characterization and Assessment of Vegetable Tannins from Guava (Psidium guajava) Leaves for Leather Tanning

For commercial leather processing, chrome tanning is the most used approach but it significantly contributes to environmental pollution. Vegetable tannins, which are large polyphenolic compounds, form strong interactions with proteins and carbohydrates, thereby enhancing the adaptability and value of vegetable-tanned leather as well as reducing environmental impact. In this study, vegetable tannins were extracted from the leaves of Guava plants (Psidium guajava) using ethanol as the solvent, facilitated by ultrasound. Extracted tannins were quantified using the Folin–Ciocâlteu reagent with ultraviolet-visible spectroscopic method. Ultrasound enhanced the extraction process producing a high yield in less time due to its mechanical, thermal, and cavitation impacts. The extracted tannins were characterized by a variety of spectroscopic techniques, including Proton (1H) Nuclear magnetic resonance, Fourier-transform infrared, and ultraviolet-visible spectroscopy. The effect of various process variables, such as temperature, solid-liquid ratio, ultrasonic power, extraction period, and powder fineness, were also investigated to optimize the extraction process. Finally, the extracted tannins were employed in leather tanning processes to assess their potential as tanning agents. The extracted tannins ensured uniform diffusion of tannins, improved thermal stability and reduced the number of tannins in effluent by 68% making it an environmentally friendly leather tanning process.

Valorization of agitated thin film dryer (ATFD)-mixed-salt from textile wastewater for its application in leather manufacturing – a sustainable approach

ABSTRACT The textile industry uses sodium chloride and sodium sulphate during the dyeing process to improve the fixation of dyes on fabrics. After wastewater treatment, the reject stream is dried resulting in mixed salts as solid wastes that are not reused. The leather industry also uses a vast quantity of salt for temporary preservation of skins/hides and as swelling-suppressing agent during the pickling (acidification) process. Thus, an attempt was made to utilize the mixed salt obtained from the textile industry to replace sodium chloride in leather processing. It was found that a 40% w/w offer of ATFD salt was able to preserve the skins for 3 months, which was on par with the preservation carried out using a similar quantity of sodium chloride in conventional preservation process. Likewise, for the pickling process, an offer of 10% w/w ATFD salt provided sufficient deswelling action when compared to conventionally used sodium chloride. However, the residual colour of the mixed salts affected the quality of the leather obtained. To overcome this, an electro-oxidation treatment was carried out to obtain decolourized salts. The COD measurements showed that the 1% solution of ATFD-3 salt reduced from 471 ± 25 to 88 ± 16 ppm. A similar trend was also seen in BOD reduction from 80 ± 12 to 18 ± 10 ppm. These results confirmed that the colour removal could be due to the degradation of the organic contaminants present in the ATFD salt. Thus, the treated ATFD salt can be reused for leather processing without affecting leather quality, thus promoting the concept of circular economy.

Comparative evaluation of tannin from banana bunch and stem syrup for leather processing

Utilization of vegetable tannins in leather processing is one of the convenient solutions to protect the environment pollution. Herein, the banana bunch and syrup of banana stem are utilized to prepare an ecofriendly tanning agent. The yield of banana bunch extraction efficiency is found 69.80 %. FT-IR analysis confirmed the presence of condensed type tanning component owing to the bearing of different polyphenolic groups. The content of tannins in extracted banana bunch and stem syrup is 3.13 % and 2.6 %, respectively. The phenolic content in the banana bunch extract is determined to be 1332.37 mg GAE/100g of dried weight and in syrup was 873.92 mg GAE/100g of dried weight. This makes it possible to be used as vegetable tanners. The extracted bunch and syrup are applied to re-tan leather and compared with conventionally used vegetable tanning agent (quebracho) in parallel. Tensile strength, tear strength and elongation percentage for the extracted banana bunch and syrup are obtained at 23.84 N/mm2, 68.26 N/mm, 47.07 %, and 22.97 N/mm2, 68.38 N/mm, 40.70 %, respectively. The softness is found 1.41 for the extracted bunch and 2.01 for the syrup. The grain crack load, distension at grain crack, strength at ball burst, distension at ball burst are 246.86 N, 13.24 mm, 530.77 N, 24.54 mm for banana stem syrup and 338.77 N, 13.42 mm, 460.65 N, 29.08 mm for bunch extract, respectively. The shrinkage temperatures recorded for banana bunch extract, syrup and Quebracho (control trial) tannins tanned leather samples are 76.5 °C, 75 °C and 84 °C subsequently. The flexing endurance of the bunch extract and syrup revealed acceptable values that are less than 4. Moreover, the bunch extract tanned leather shows greater thermal stability and for syrup it is similar with the quebracho tanned leather. All the results are satisfactory compared to the control trial. Finally, tanned leather is evaluated to assess the possibility of the newly developed tannin which proves its efficiency as a potential source of tanning material for the leather industry.

Isolation of Multidrug-Resistant Bacteria from Raw Hides, Salted Hides, and Tannery Wastewater and Their Heavy Metal (Cr) Tolerance

Numerous leather products are created from cattle hides and skins. However, the processing of these products can release toxic heavy metals, including chromium into the environment, leading to health hazards and environmental pollution. This study aims to isolate and identify multidrug-resistant bacteria from rawhide, salted hides, and tanneries in different areas of the Savar region in Dhaka City, Bangladesh. The secondary objective is to determine the heavy metal tolerance and Minimum Inhibitory Concentration (MIC) of Cr against all isolated bacteria. The study found 206 bacterial isolates from three areas: Polashbari Kathaltola, Polashbari Bazar, and Savar Hemaythpur. Rawhide yielded 100 (48.54%) bacterial isolates, salted hide yielded 80(38.83%) isolates, and tannery wastewater yielded only 26 (12.62%) isolates. Further, Bacillus spp. (60) was the most common isolated bacteria. The other identified bacteria were Pseudomonas spp. (46), Staphylococcus spp. (40), Proteus spp. (40), and Escherichia coli (20). The isolated strains showed multidrug resistance, with Staphylococcus spp. Being highly resistant to Erythromycin (100%), followed by Trimethoprim (95%) and Tetracycline (88%). Pseudomonas spp. Were highly resistant to Azithromycin (100%) and Gentamycin (100%). The MIC and the MIC breakpoint determined the screening and evaluation of Cr tolerance against bacteria, and among the isolated bacterial isolates, Bacillus spp. showed a MIC breakpoint of 600 ppm (11.52mM) for Cr tolerance. The isolated heavy metal-resistant bacteria are useful in the bioremediation process and can aid in recovering and removing heavy metals from environmental effluents, thus preventing adverse effects on humans and animals. The government and leather companies should take legal responsibility for proper leather processing to ensure a preventative approach for safe public health. Otherwise, carcinogenic heavy metals can cause cancer in humans.

A New Synthesis Method and Characterization of Graphene Oxide Nanocomposites for the Leather Tanning Process

Environmental pollution caused by wastes generated from chrome tan is a major concern nowadays. This study aimed to develop an eco-friendly alternative tanning agent using graphene oxide (GO) based nanocomposite materials. GO was synthesized by a new approach with modification of the Hummers method. Two types of GO-based nanocomposites, GO-TiO2 (GT) and GO-TiO2-PEG (GTP) were prepared by adding TiO2 nanoparticles and polyethylene glycol (PEG) as surface modifiers. They were successfully applied to leather tanning processes at different concentrations (2%, 4%, and 6%). Both synthesized GO, GO-nanocomposites, and the resulting tanned leathers were characterized by Scanning Electron Microscopy (SEM), Thermogravimetric Analysis (TGA), and Fourier-transform Infrared Spectroscopy (FT-IR). Different physico-mechanical properties of leathers tanned with nanocomposites were evaluated and the results were compared with chrome-tanned leathers. The tensile strength of chrome-tanned leather was 223 (kg/cm) whereas the maximum tensile strength was found at 228 (kg/cm) and 233 (kg/cm) in 6% GO-TiO2 and GO-TiO2-PEG tanned leathers respectively. The environmental pollution impact of the effluents generated by the new tanning process was assessed. The COD of effluents generated from chrome tanning was 4800 ppm which was significantly reduced to 2400-1440 ppm and 2880-1920 ppm when GO-TiO2 (GT) and GO-TiO2-PEG (GTP) were applied in leather tanning respectively. The TDS and BOD were found at 183.8 and 200 ppm in conventional chrome-tanned wastewater which were significantly reduced to the range of 47.5-18.3 and 100-50 ppm respectively in liquid wastes obtained from the GO-composite tanning process. The maximum reduction of COD, BOD, TDS, and TSS in leather waste liquid was found with the application of 2% GO-nanocomposites in tanning. The results revealed that leathers tanned with nanocomposites possess characteristic properties which were very similar to those observed in chrome-tanned leathers whereas the new tanning agents drastically reduced the intensity of pollutants in leather effluents. The application of new nanocomposites in the leather tanning process is an innovative effort. This new nanocomposite-tanning method showed minimal consequences regarding environmental pollution with the generation of less toxic effluents from the respective tanning process.

Nanoparticle Usage in Leather Processing: Worker Safety and Health

Nanoparticle Usage in Leather Processing: Worker Safety and Health

ACTIVATED CARBON DERIVED FROM GROUNDNUT SHELL AND RICE HUSK FOR THE ADSORPTION OF HEAVY METALS IN TANNERY WASTEWATER

The Effluents from tanneries are considered to be one of the major environmental pollutants from industries. The challenge from leather processing arises from the nature and quality of the chemicals used along with the amount of wastes generated and discharged. Heavy metals present in tannery wastewater pose a significant risk to both the environment and public health. This study investigates the use of activated Carbon produced from Composite of Groundnut shell and Rice husk (GR-AC) to remove heavy metals (Pb, Cr and Cd) from tannery wastewater. The raw material was carbonized at temperature of 400 ͦ C for 1 hour to obtain bio char. The obtained char was impregnated with NaOH and H 3PO 4 for 24 hours thereafter, filtered and washed several times until a neutral pH was obtained. A measured amount of the adsorbent, 0.5g was introduced into 250mL vessel with 50mL wastewater, it was stirred at 250rpm for 60minutes and later subjected to centrifugation and the concentrations of residual Lead, Chromium and Cadmium was determined using Flame Atomic Absorption Spectrometry. The produced adsorbent was characterized using Fourier transform infrared (FTIR) spectroscopy, Energy-dispersive X-ray fluorescence (EDXRF) and scanning electron microscopy (SEM), elemental composition analysis. The effects of adsorbent dosage and contact time on the adsorption process were studied in a batch system. From the research conducted, it shows that pH, adsorbent dosage, contact time, initial Concentration and temperature plays a vital role in the uptake of heavy metals. Optimal conditions for effective adsorption were determined at a pH range of 7 to 8, an adsorbent dosage of 0.5g, contact time of 60 min and a temperature of 40 0C. The maximum adsorption capacities of Pb, Cr and Cd adsorbed onto GR-AC were found to be 98.2, 82.4 and 75.2 mg/g respectively. Therefore, the GR-AC can be effectively utilized as agricultural waste to remove heavy metals in tannery effluents.

Characterization and recognition of three-dimensional excitation-emission matrix spectra of wastewater from six typical categories

In this study, we analyzed the characteristics of three-dimensional excitation-emission matrix spectra (EEMs) of 150 samples from five industrial wastewater types and domestic sewage to track water pollution sources effectively. We then developed a recognition model for wastewater EEMs by establishing a feature dataset containing fluorescence peak values and parameters derived from EEMs, integrated with machine learning techniques. This model enables the rapid and precise identification of pollution sources. Our findings suggest that although the EEMs of the six wastewater categories are distinct, visual differentiation is challenging. This was confirmed by cosine similarity assessments, showing some samples with low within-group (< 0.8) and high between-group (> 0.95) similarities. Despite significant variations in EEMs features across wastewater categories, identifying specific pollutants remains difficult, especially for pulp mills and leather effluents. Among the tested classification algorithms, Support Vector Machine (SVM) achieved the highest performance with 91.7 % accuracy, 94 % precision, 91 % recall, and 92 % F1-score, outperforming K-Nearest Neighbors and Partial Least Squares Discriminant Analysis. The SVM significantly improved identification accuracy for pulp mill and leather processing wastewaters compared to other models. To enhance identification accuracy, further exploration of EEMs features and expanding the training dataset are recommended. Combining EEMs features with machine learning presents a promising method for improving water pollution supervision and source tracing in environmental management practices.

Biomimetic and Multifunctional Polypeptides for Green Leather Processing: Design, Preparation, and Properties

Biomimetic and Multifunctional Polypeptides for Green Leather Processing: Design, Preparation, and Properties

Phytoremediation potential of Pistia stratiotes, Eichhornia crassipes, and Typha latifolia for chromium with stimulation of secondary metabolites

Anthropogenic activities have significantly polluted the natural environments all over the world. Leather processing industries release toxic heavy metals through their effluents posing a great threat to the environment. Chromium (Cr) is the major component of tannery effluents. We designed this experiment with the aim to remediate Cr from effluents of tanneries through phytoremediation. We selected three native macrophytes i.e. Pistia stratiotes, Eichhornia crassipes, and Typha latifolia to grow in a set of Constructed Wetland systems (CWs) with a continuous supply of tannery wastewater. T. latifolia was the most efficient phytoremediator of these macrophytes as it reduced the Cr content by 96.7%. The effluent after passing through the CWs containing T. latifolia showed only 0.426 mg/L Cr content. All macrophytes showed an enhanced phytochemical activity such as total antioxidant activity (TAA), total reduction potential (TRP), total phenolic content (TPC), total flavonoid content (TFC), and DPPH radical scavenging activity (DPPH) substantially. The activation of antioxidant mechanism may have contributed towards robust defense system of these plants for survival in excessive Cr contaminated media. Also, these macrophytes showed a positive relationship in reducing Cr content from tannery wastewater. Results of this study could help in effective sustainable management of aquatic environments contaminated with metal pollutants from human activities.

Efficient Dye Removal Strategies: Exploring the Role of Biochar

The surge in industrial activities, notably in sectors such as textiles, leather processing, and paper manufacturing, has led to a considerable rise in synthetic dye discharge into the environment, posing significant threats to ecosystems and human health. Traditional wastewater treatment methods have struggled to effectively address dye pollution due to the complex nature of these pollutants. In response, biochar has emerged as a promising solution, offering unique physicochemical properties that make it an excellent adsorbent for dye removal. This review explores the role of biochar in dye removal, focusing on its surface properties, production methods, and adsorption mechanisms. Biochar's extensive surface area, porosity, and surface functional groups play crucial roles in facilitating dye adsorption. Various production methods, such as pyrolysis, hydrothermal carbonization, and superheated steam torrefaction, influence biochar properties and effectiveness in dye removal applications. Surface modification techniques enhance biochar's dye removal capacity and regeneration potential, enabling its reuse in wastewater treatment. Moreover, the surface charge of biochar influences electrostatic interactions with dye molecules, affecting adsorption efficiency. Understanding biochar's surface charge is essential for optimizing dye removal processes. Overall, biochar holds promise as a sustainable and efficient adsorbent for mitigating dye pollution, offering valuable insights for environmental remediation efforts.

Considerations on the creative activity of leather and fur craftsmen of the south Republic of Moldova

The purpose of the present study is to identify folk craftsmen in the localities of the south Republic of Moldova who, through their activity, preserve and promote the traditions of leather and fur processing. The elucidation of the proposed aspects was carried out on the basis of the bibliographic study of ethnographic sources, informative and illustrative materials collected at festivals, fairs, and exhibitions of traditional crafts, as well as field documentation. Pieces of clothing, accessories, harness articles, part of the material culture of Bessarabian Romanians, were examined. The work highlights the need to valorize and promote the cultural heritage of the country, to affirm the cultural identity at the local and regional level.

Unleashing the potential of leather waste: Biogas generation and cost savings through semi-continuous anaerobic co-digestion

Leather processing is notorious for generating substantial amounts of polluting and putrescible organic waste, usually ending up in landfills or incineration. This study aimed to assess the potential of biogas production, waste treatment efficiency, and energy and cost savings benefits when scaling up the anaerobic co-digestion of leather processing wastes. The study focused on three waste types: tannery primary sludge (TPS), leather fleshings waste (LFW), and tannery wastewater (TWW). Semi-continuous anaerobic digestion experiments were conducted using three bench-scale reactors (R1-R3) over five phases; phases I and II were the startup and stabilization. In phase III, with an organic loading rate (OLR) of 0.6 kgVS/m3/d, the R2 reactor achieved an average of 0.323 m3 methane/kgVS added/day. This performance surpassed the other reactors by 39.14% (R1) and 41.29% (R3). In phases IV and V, using TWW instead of tap water for substrate dilution at different ratios (25–100%) reduced methane yield by 3.32–11.73% compared to the reactor that used tap water. The study further revealed that a medium-sized anaerobic reactor treating tannery wastes could reduce electric energy consumption by 3.64% and thermal energy consumption by 5.20%. This showcases the energy-saving benefits of co-digesting tannery wastes rather than disposing them in landfills. Using tannery wastes instead of traditional disposal methods resulted in approximately 94.68% savings in electric consumption and 45.03% in thermal energy consumption. This study offers a promising approach for sustainable leather waste treatment, biogas production, and considerable energy and cost savings compared to conventional disposal methods like landfilling.

Eco-friendly Chrome Tanning of Leather using Ultrasound Technique

This article describes the development of an environmentally friendly chrome tanning process of leather using ultrasound. Most of the leathers are tanned by the conventional method using basic chromium sulfate. It is one of the most polluting and time-consuming steps in leather processing. Investigations were carried out on ultrasound assisted eco-friendly tanning process so that the chrome tanning agent could provide better quality leather. Effects of using ultrasound in chrome tanning process were studied at different pH, tanning time, tanning agent dosage, and then compared with that of conventional method. Tanned leathers were characterized by scanning electron microscopy (SEM), photomicrographic analysis, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and energy dispersive X-ray (EDX). SEM analyses of the surface and cross-section of the tanned leather showed that fiber structures were not affected by ultrasound. It was also found that the shrinkage temperature of leather tanned with ultrasound was increased by about 5-29 °C. Chrome uptake and content were found to increase by 30-50% and 1-7%, respectively. Tanning time was shortened from 6 hours to 2 hours and the quantity of leachable chromium in ultrasound assisted chrome tanned leather was also decreased significantly. The noteworthy enhancing effects have been attributed largely because of the increased penetration of tanning agents into pickled leather. Photomicrographic analysis of the cross-section of the tanned leather also showed a higher penetration of tanning agents in presence of ultrasound.

Adsorption-oxidation process for dyestuff removal from tannery wastewater

In leather processing, dyeing is one of the most important operations. A significant amount of wastewater is emitted from the tannery after the dyeing operation. The dyeing wastewater harms aquatic life. Removal of dyestuffs from the real dyeing wastewater has become a great challenge to lessen the tannery's pollution load. In this work, the adsorption-oxidation process has been studied for acid dyestuff removal from real tannery effluent. The preparation of cost-effective adsorbent was performed through thermal alteration of liming sludge leftover from a tannery. Adsorbent had been distinguished, implementing Fourier Transform Infrared (FTIR) Spectroscopy, Energy Dispersive Spectrometer (EDS), Scanning Electron Microscope (SEM), and X-ray diffraction (XRD) both immediately before and following. The parameters of adsorbent dosage, oxidant dosage, contact time, settling time, oxidant reaction time, and initial pH were performed to maximize the efficiency of dyestuff removal from tannery wastewater. Adsorption was performed without prior regulating the initial pH to remove dyestuff and other pollutants present in the effluent. Then, oxidation was performed to degrade the remaining color of the dyestuff. After adsorption-oxidation, the treated effluent’s pH level was 6.9. The combined effect of adsorbent and oxidant results showed dyestuff removal at 75.82%. The co-efficient obtained from Pseudo-Second-Order (PSO) kinetics, Freundlichisotherm, and thermodynamic analysis, elucidated the adsorption responseof an exothermic chemisorption reaction, with significant interconnectivity between adsorbent and dyestuff molecules. The mechanism of adsorption of Green V dyestuff on liming sludge adsorbent was also studied. The reusability study revealed that the regeneration efficiency was 91.85% after the 4th cycle of the adsorption–regeneration process. Moreover, the process reduced biochemical oxygen demand (BOD) and chemical demand (COD) was 72.41%, and 58.63%, respectively from the dyeing wastewater. The present approach would be implemented as an affordable and sustainable methodology to remove acid dyestuff from real tannery wastewater.

Toward Sustainable Leather Processing: A Comprehensive Review of Cleaner Production Strategies and Environmental Impacts

Toward Sustainable Leather Processing: A Comprehensive Review of Cleaner Production Strategies and Environmental Impacts