Journal of Chemical Society of Nigeria

OPTIMIZATION OF COAL TO BIOMASS RATIO FOR ENHANCED MECHANICAL AND COMBUSTION PROPERTIES OF COAL-CASSAVA STALK (Manihot esculenta) AND DETAR SHELL (Detarium senegalense) BRIQUETTE BLENDS

N. O. Eze, T. U. Onuegbu, I. Ogbuewu, W. O. Oti — Mon, 30 Jun 2025 00:00:00 +0000

This study investigated the optimization of coal-biomass ratio to produce briquettes from cassava stalk and detar shell. Briquettes consisting of different ratios of coal to biomasses were produced to evaluate the effect of the materials on the properties of the briquettes. Proximate, mechanical, and combustion analyses were conducted on the briquettes using standard procedures. The results showed that the addition of biomass improved the mechanical properties of the briquettes, increasing their durability and compressive strength. The coal briquettes blends exhibited superior properties, including higher calorific values, shorter water boiling times, and longer burning times, compared to biomass-only briquettes. The optimum coal-biomass ratio for both the cassava stalk and detar shell coal briquette blends was found to be 60% coal to 40% biomass. The properties of the optimized briquettes were comparable to those reported in literature. This study demonstrated the potential of coal briquette blends of cassava stalk and detar shell as a sustainable and efficient energy solution.

ELECTROCHEMICAL EVALUATIONS OF PALLADIUM/RUTHENIUM BINARY CATALYST ON VARIOUS NANOSTRUCTURED SUPPORT MATERIALS FOR DIRECT METHANOL FUEL CELLS

A. J. Sabejeje, O.A. Obijole, A. A. Izuagie — Mon, 30 Jun 2025 00:00:00 +0000

Palladium/Ruthenium (Pd/Ru) binary catalyst supported by graphene oxide (GO), nitrogen doped graphene oxide (NGO), multi-walled carbon nanotubes (MWCNTs), nitrogen doped multi-walled carbon nanotubes (N-MWCNTs) and carbon nanofibers (CNFs) were synthesized in this work. The MWCNTs and CNF were commercial but functionalized. The GO was synthesized by modified Hummer’s method. Thereafter, the GO and MWCNTs were doped with nitrogen. The catalysts were synthesized using modified polyol method. The surface areas of the supports were analysed using Brunauer-Emmett-Teller (BET) Technique where N-MWCNTs showed the highest surface area of 219.495 m2/g compared to other supporting materials. The structures of supports and catalysts were examined using Fourier Transform Infrared Spectroscopy (FTIR) and X-ray Diffraction (XRD) respectively. The FTIR showed that the surface of the support materials exhibits oxygen containing functional groups while the XRD confirmed that the catalysts exhibit face-centered crystal (fcc) structure of Palladium with crystallite sizes varying from 0.5 nm to 11.7 nm. High Resolution Transmission Electron Microscopy (HR-TEM) image showed spherical and agglomerated Pd/Ru nanoparticles and narrow particle size distribution dispersed on the support materials with particle sizes in the range of 0.9 nm to 11.6 nm. For electrochemical evaluation, Pd/Ru-NGO performed best. This can be accorded to better electroactive surface area, presence of dopant nitrogen in NGO and synergistic interaction between the Pd/Ru nanoparticles and the NGO support material. Hence, NGO has been proved in this study to be the best support materials for carbon supported Pd/Ru binary catalyst among other synthesized carbon support materials for direct methanol fuel cells.

INTERACTIVE EFFECTS OF SELECTED HEAVY METALS ON IRON TOXICITY IN LOWLAND RICE (Oryza sativa L.)

A. A. Koleola, J. O. Jacob, R. B. Salau , P. Tsado — Mon, 30 Jun 2025 00:00:00 +0000

Iron toxicity is a major challenge in lowland rice production, with other heavy metals influencing iron uptake and overall plant responses. This study examined the interactive effects of copper (Cu), cobalt (Co), nickel (Ni), and arsenic (As) on iron (Fe) uptake in the FARO-44 rice variety. Paddy soils were processed, placed in 75 pots, and treated with five Fe²? concentrations (0, 100, 200, 300, and 400 mg kg?¹) as FeSO?. Additional treatments of Cu (36 mg kg?¹), Co (50 mg kg?¹), Ni (35 mg kg?¹), and As (20 mg kg?¹) were applied across Fe levels. Plant height and tiller count were recorded at 33, 47, 65, and 116 days after transplanting (DAT). The study found that while iron is essential for rice growth, excess iron initially inhibited growth (33–47 DAT), but plants later adapted and benefited from higher concentrations (65–116 DAT). The interaction of heavy metals with iron intensified toxicity, with arsenic posing the most significant risk. These findings highlight the importance of managing soil iron levels within an optimal range and considering other heavy metals to mitigate toxicity in lowland rice cultivation.

DETERMINATION OF ORGANOCHLORINE AND SYNTHETIC PYRETHROID PESTICIDE RESIDUES IN FRESH PEPPER FROM SELECTED FARMLANDS IN EDOZHIGI, GBAKO L.G.A., NIGER STATE, NIGERIA

Mon, 30 Jun 2025 00:00:00 +0000

In this research, the concentrations of Synthetic pyrethroids (SPP) and Organochlorine (OCP) pesticide residues level in fresh Pepper (Capsicum annum) from selected farms in Edozhigi, Gbako Local Government area of Niger state, Nigeria was determined using QuEChERS and GC-MS for sample preparation and analysis respectively. The results obtained from this research indicates the presence of OCP and SPP residues including: Heptachlor, Aldrin, Dieldrin, Heptachlor epoxide, Endosulfan II and Endosulfan sulfate; Lambda-cyhalothrin, ?-Cypermethrin and zeta-Cypermethrin with concentrations of 1.33 mg/kg, 1.55 mg/kg, 0.33 mg/kg, 0.22 mg/kg,1.31 mg/kg,0.45 mg/kg and 1.00 mg/kg, 1.29 mg/kg and 1.08 mg/kg. All the detected OCPs were above the maximum residue limits. Indeed, these concentrations of both the organochlorine and pyrethroid pesticides detected in the pepper sample analysed were observed to be above the maximum residue limits (MRLs) by the Codex 2009 (WHO and FAO), and hence at alarming levels.

CHEMICAL ANALYSIS OF ESSENTIAL OIL OF Eucalyptus camaldulensis Dehn. AND EVALUATION OF THE ANTIOXIDANT AND ANTIMICROBIAL ACTIVITIES AGAINST SOME MICROBES.

O. O. Fatunmibi, I. S. Njoku, O. T. Asekun, J. O. Ogah — Mon, 30 Jun 2025 00:00:00 +0000

The chemical profiling, antioxidant capacity, and antimicrobial effects of the extracted essential oil from the leaves of Eucalyptus camaldulensis Dehn. grown in Oyo State, Nigeria, were studied. The extracted essential oil by hydro distillation utilizing the Clevenger apparatus yielded 0.99% volume per dry weight and was analyzed using Gas Chromatography-Mass Spectrometry (GC-MS). The primary constituents identified were cis-Sabinol (37.7%), Linalool (13.64%), ?-Cadinol (9.81%), ?-Muurolene (5.03%), and Epicubebol (3.99%). Microbial inhibition was evaluated using the agar diffusion method against microbes that cause skin infections in humans, namely, Streptococcus mutans, Escherichia coli (ATCC 25922), Staphylococcus aureus (ATCC 29213), and Candida albicans (ATCC 10231), while the in vitro antioxidant activity was assessed using DPPH, nitric oxide scavenging activity, and lipid peroxidation tests. The volatile oil exhibited notable inhibition zones (mm) against Streptococcus mutans (39.00±0.71), Escherichia coli (39.00±0.0), Staphylococcus aureus (33.00±0.71), and Candida albicans (39.00±0.71) and also showed strong concentration-dependent free radical scavenging activity. These findings reiterate the use of Eucalyptus camaldulensis Dehn. Essential oil in cosmetic formulations to promote wound healing and to fight skin microbial invasions.

SYNTHESIS AND CHARACTERIZATION OF Hura crepitans SEED OIL ALKYD RESIN FOR SURFACE COATING FORMULATION SYNTHESIS AND CHARACTERIZATION OF Hura crepitans SEED OIL ALKYD RESIN FOR SURFACE COATING FORMULATION

I. M. Adejare, A. Awosanya, C. O. Eromosele — Mon, 30 Jun 2025 00:00:00 +0000

The study aimed at synthesizing and characterizing alkyd resin from Hura crepitans seed oil as a surface coating material. H. crepitans seed oil was extracted from its oil-bearing seeds via Soxhlet extraction with n-hexane. The alkyd resin synthesis involved reaction of 50 % oil length triglycerides by alcoholysis process to obtain H. crepitans seed oil monoglycerides at 230°C, followed by modification with phthalic anhydride via polyesterification process at 220°C. Fourier Transform Infra-Red (FT-IR) was used to confirm the ester linkage present in the alkyd resin and compared with the H. crepitans seed oil. The physicochemical properties of H. crepitans seed oil determined for its suitability as a potential material were: acid, peroxide, iodine, saponification values and % free fatty acid with respective values of 9.66 mgKOH/g, 2.84 mgEq/kg, 160.73 gI2/100g, 205.00 mgKOH/g and 2.24 %. The acid, iodine and saponification values of the synthesized alkyd resin were 6.65 mgKOH/g, 82.40 gI2/100g and 308.00 mgKOH/g respectively. The chemical resistance of the synthesized alkyd resin showed that the film formed from the polyester has a good resistance to chemicals except that it is susceptible to alkaline hydrolysis, indicating its poor resistance to alkali solution. The result of the drying properties obtained revealed that the polyester gotten from H. crepitans seed oil have a high drying speed in the presence of drying agent and exhibit excellent adhesion which indicates better protection of substrates. Hence, H. crepitans seed oil alkyd resin shows promising ability as a binder in surface coatings formulation.

A COMPARATIVE ANTIDIABETIC STUDY OF THE MORPHOLOGICAL PARTS OF Morinda lucida (BENTH).

E. A. Olanudun, F. G. Famuyiwa, K. O. Faloye, M. D. Ayoola, S. O. Famuyiwa — Mon, 30 Jun 2025 00:00:00 +0000

Diabetes mellitus (DM) is a metabolic syndrome that contributes to a consistent decline in the life expectancy of the world's inhabitants. Morinda lucida (Brimstone tree) is an evergreen tree widely found in Africa, including Nigeria. This study justified the antidiabetic efficacy of the morphological parts of M. lucida. The fruit, leaf, stem bark, and root bark were shade-dried, extracted with methanol, filtered and concentrated to obtain the extracts that were thereafter assayed for their glucose-lowering effect using graded doses of 100, 200 and 400 mg/kg. The most active dose in glucose-lowering studies was adopted for the streptozotocin-induced model in vivo. The fruit and the leaf extracts at 200 mg/kg demonstrated the highest percentage blood glucose level reduction of 68 and 62% respectively in the glucose-lowering assay, followed by the 400 mg/kg dose of the root bark extract (62%) and 200 mg/kg of stem bark extract (29%). Similarly, the leaf and fruit extracts replicated their excellent activities in the streptozotocin-induced diabetic study with 79 and 80% blood glucose level reduction respectively, followed by the stem bark at 73% and root bark at 71%. The results obtained for the extracts in both antidiabetic assays are comparable (p>0.05) with glibenclamide (5 mg/kg). Future research should focus on isolating active compounds and conducting mechanistic studies to better understand the therapeutic effects of the fruits and leaves.

STUDIES ON THE PREPARATION AND CHARACTERIZATION OF METAL-DOPED BIOCHAR

B. E. Imokhai, C. M. Ejimadu, F. E. Okieimen — Mon, 30 Jun 2025 00:00:00 +0000

The physicochemical properties of groundnut husk biochar: pH, 6.90, bulk density (g.cm-3) 0.39 ± 0.02, cation exchange capacity (mmol.kg-1) 42.50 ± 1.36, electrical conductivity (ms.cm-1) 3.83 ± 0.14 and proximate composition (wt %), moisture content 24.53 ± 1.01, ash content 4.76 ± 0.08: volatile matter 57.48 ± 1.24 and fixed carbon 4.93 ± 0.06 indicated that the surface chemistry could retain nutrient elements relevant to agronomic benefits. The proximate composition was used following the to the Parikh et al. and Klasson equations to deduce the ultimate composition (wt%), C 29.30 and 31.31; H 3.72 and 4.92 and O 28.86 and 27.33, respectively for groundnut husk biochar and the allowed values of H/C 0.13 and 1.57, and O/C 3.72 and 4.92 respectively to obtained for the biochar. These values a degree of recalcitrant and stability of the groundnut husk biochar to degradation. The FTIR spectrum of the metal-doped biochar revealed absorption band at 550 cm-1 which was absent in the spectrum of the unmodified biochar. The elemental oxygen contents of the metal-doped biochar obtained for EDX was markedly higher than in the unmodified biochar; while the elemental carbon in the unmodified biochar (89.56%) was markedly higher than the level 43.20% in the modified biochar. The specific surface area of the iron-doped biochar (5.06 m2.g-1) was found to be markedly lower than that of the unmodified biochar 110.09 m2.g-1. The porous structures, pore diameter (nm) and pore volume (cm3) of the iron-doped 10.28 and 0.09 where markedly higher than the corresponding value of 1.67 and 0.02 for the unmodified biochar.

INVESTIGATING THE ELECTRICAL PROPERTIES AND POTENTIALS OF MAGNESIUM-ION ELECTROLYTE IN BINARY SOLVENTS OF PROPYLENE CARBONATE AND ACETONITRILE

N. J. Maduelosi, B. B. Dume, P. M. Amaibi — Mon, 30 Jun 2025 00:00:00 +0000

This study work provides information on the interaction of mixed solvents of propylene carbonate (PC) and acetonitrile (AN) for magnesium batteries. Varying mole fractions of mixed solvents with the salt were prepared and characterized. Density, viscosity, conductivity, dielectric constant, Critical distance for ion pair formation, and Grunberg Nisan’s d parameter were measured at different compositions of PC, molar concentration of Mg(ClO4)2 (0.1, 0.5, 1.0 and 2.0 M) and temperatures (25, 30, 40 and 50 °C) were monitor at different interval. It was observed that density values decreased with a decrease in the mole fraction of PC and an increase in temperature, Viscosity values decreased with an increase in the mole fraction of AN and an increase in temperature, Molar conductivity values increased with increasing concentration of the solution, and the highest value was recorded at 0.5-mole fraction of PC in 2.0 M solution, The dielectric constant of the mixture shows changes in values as the mole fractions of the mixtures changed. Critical distance for ion pair formation was obtained at mole fractions 0.3 and 0.65 of PC. These properties were affected by ion-solvent and solvent-solvent interactions in the mixtures. The varying temperatures studied demonstrated that the battery remains stable even at high temperatures as the mixing ratio of the organic solvents for optimal magnesium ion battery performance is established at 0.5-mole fractions of PC with a molar conductance of 20.164 Scm2 mol-1. The results have been interpreted based on the intermolecular interactions among the component molecules of the systems.

Synthesis, Characterization and Application of Polyaniline nanofibre for the Sequestration of Pb2+ and Cr6+ from aqueous solution

W. C. Ogwu, E. A. Onoabedje, H. O. Abugu, U. S. Oruma — Mon, 30 Jun 2025 00:00:00 +0000

Polyaniline (PANI) nanofibre as an adsorbent, was used in the sequestration of Pb2+ and Cr6+ (M2+) from aqueous solution. PANI nanofibre adsorbent was synthesized through chemical oxidative polymerization of aniline under HCl as an acidic medium using ammonium peroxydisulphate as initiator. Isothermal, kinetic models and thermodynamic studies were also conducted. The PANI was characterized using FTIR and SEM. Through a batch adsorption process, the synthesized PANI was applied in the sequestration of Pb2+ and Cr6+ from aqueous solution. The spectroscopic result revealed the presence of Imine and amine functional groups on the surface of PANI nanofibre. The SEM showed a rough surface and several pores on the surface of the PANI nanofibre. These are properties responsible for metal adsorption unto the PANI nanofibre. The equilibrium data best fitted unto Freundlich isotherm model with correlation coefficient (R2) values of 0.907 and 0.928 for Pb2+ and Cr6+ respectively, suggesting that the adsorption sites were heterogeneous with multilayer adsorption coverage. Freundlich exponent 1/n > 1 (n= degree of the surface heterogeneity) indicated favorable adsorption. The Kinetic studies revealed that the sorption process best agreed with the Pseudo-second order and Elovich Kinetic Models indicating that chemisorptions and surface heterogeneity of the adsorbent govern the adsorption process. Thermodynamic data (entropy, Gibbs free energy and changes in enthalpy) indicated spontaneous and endothermic sorption processes. The synthesized PANI nanofibre adsorbent efficiently removed Cr6+ and Pb2+ with 0.64 mg/g (87.4%) and (0.58 mg/g) 74.6% as adsorption capacities/percentage removal efficiency from aqueous solution respectively.

FORMULATION, CHARACTERIZATION AND POTENTIAL HEALTH BENEFITS OF DOPED ZnO IN CALAMINE LOTION

O. S. Bull, J. L. Konne, J. B. Nwinaa-ie — Mon, 30 Jun 2025 00:00:00 +0000

In this study, we report on the formulation, characterization and potential health benefits of doped ZnO in calamine lotion. Also, antibacterial activities of the calamine lotion towards Staphylococcus aureus and Pseudomonas aeruginosa were investigated. The nanoparticles were prepared using sol-gel (alginate) technique. The samples were characterized using X-ray Diffraction (XRD) for structural determination (Crystallinity), Energy Dispersive X-ray Fluorescence (EDXRF) for elemental composition and Fourier Transform Infrared (FTIR) spectrophotometer for the functional groups. of the Ag-doped Fe3O4 nanoparticles with and without alginate (control experiment) The XRD patterns were the estimated particle sizes of Cu-doped ZnO were 32.10 (alginated) and 26.10 nm (without alginate) while those of ZnO, 24.80 and 19.30 nm respectively, indicating that the alginated phases were of larger particle sizes. The XRD patterns of the ZnO phases showed broader peaks. The EDXRF results confirmed that doping was successful with minor percentages for the dopant. The FT-IR results showed absorption peaks to the corresponding vibrational bands present. The nanoparticles were further applied in calamine lotion production and the lotion was tested for its antibacterial susceptibility using conventional Kirby-Bauer Agar. The susceptibility results showed that the commercial and the sample calamine lotions were both susceptible for the treatment of E.coli and S. aureus with the alginated Cu-doped ZnO giving the best E.coli clearance of 27.0 mm and it is recommended for use in calamine lotion production.

FOURIER TRANSFORMED INFRA-RED (FTIR) ANALYSIS AND ANTIMALARIAL ACTIVITY OF METHANOL STEM BARK EXTRACT OF Acacia sieberiana DC (FABACEAE)

Mon, 30 Jun 2025 00:00:00 +0000

Acacia sieberiana is a renowned medicinal plant with wide range of therapeutic properties. This research is aimed at investigating the functional groups present and the antimalarial activity of methanol stem bark extract of Acacia sieberiana. Preliminary phytochemical screening of the crude extract indicated the presence ofcardiac glycosides, tannins, flavonoids, alkaloids, phenols, saponins and steroids while anthraquinones were absent.FTIR analysis of the extract showed stretching vibrations for C=O at 1720cm- 1, O–H at 3587.72cm-1, N–H at 3742.03cm-1, C–H at 2931.90cm-1, bending vibrations for arenes/arylbenzenes between 850 to 1250cm-1. The LD50 of the extract was found to be 2828.42mgKg-1 bwt and is considered safe. Average suppression of up to 92% was recorded for the highest dose of 300mgKg- 1bwt of the extract on Plasmodium berghei NK65 parasite.

PREPARATION, CHARACTERIZATION, AND PHARMACEUTICAL EXCIPIENT POTENTIALS OF MICROCRYSTALLINE CELLULOSE FROM Gmelina arborea WOOD DUST WASTE

M T Baker, J T Aasa, A T Kola-Mustapha, O S Oguntoye — Mon, 30 Jun 2025 00:00:00 +0000

Poor waste management in developing countries like Nigeria has caused environmental problems and lost economic potential, underscoring the need for better waste processing. The study explores turning agricultural waste, specifically Gmelina arborea wood dust, into microcrystalline cellulose (MCC) for pharmaceutical use. Cellulose was extracted from Gmelina arboreal wood dust waste via chemical treatment; MCC was prepared via acid hydrolysis in 2M hydrochloric acid; Various techniques were used to analyze the cellulose and MCC, focusing on their functional groups, structure, crystallinity, thermal stability, and elemental makeup. The FTIR analysis indicated the successful extraction of cellulose and preparation of MCC from the cellulose produced, with notable absorption bands at 3330, 2900, 1430, 1374, 1050 and 890 cm-1 associated with –OH stretching, saturated aliphatic -C-H stretching, -CH2, -CO asymmetric bridge stretching, -C-O-C glucopyranose ring vibration and Crystallinity band respectively. The diffraction patterns of the cellulose and MCC showed peaks at 2? angles at 14.5°, 17°, 22.7° and 35.5° with crystallinity indices values of 72% and 79.6% for cellulose and MCC; the thermal degradation pattern of the samples indicated that the MCC sample is more thermally stable as expected, than the cellulose. The SEM analysis indicated that the Cellulose are fibrous, while the MCC appeared like short separated firbres indicating the successful hydrolysis of the cellulose sample while the EDS showed that the samples were composed mainly of CHO indicative of pure MCC samples. The pH, ash content, moisture content, hydration capacity showed the MCC samples were neutral, of high purity with minimal impurity and good flow properties. In conclusion, Gmelina arborea wood dust MCC is a valuable source for direct compression excipients (DCE) in pharmaceuticals. The study promotes using cellulose from agricultural waste as a viable alternative for pharmaceutical excipients and as a binder in paint and cosmetics.

SYNERGISTIC EFFECTS OF MIXED TANNIN EXTRACTS ON THE PHYSICOMECHANICAL PROPERTIES OF TANNED LEATHER

M. Y. Bammai, C. E. Gimba, K. I. Omoniyi, I. Akawu — Mon, 30 Jun 2025 00:00:00 +0000

This study evaluates the synergistic effects of mixed tannin extracts from Bagaruwa (Mimosa), Parkia biglobosa, Divi-divi, and their combinations on the physicomechanical properties of tanned leather. Mechanical testing revealed that samples treated with mixed tannins exhibited enhanced tensile strength, elongation, and force resistance compared to single-tannin treatments. Notably, the Bagaruwa-Mimosa combination (Sample BI) achieved the highest force resistance (39.15 kg) and tensile strength (15.07 MPa), whereas Parkia biglobosa only treatments showed lower strength and flexibility. Addition of metabisulphite to Parkia tannin improved mechanical performance, confirming additive synergy. Thermal stability measured by shrinkage temperature varied significantly across samples, with highest values reaching 85.0°C (Sample III), indicating superior hydrothermal resilience in mixed tannin treatments. Water vapor permeability and water absorption tests demonstrated that tannin composition influences leather breathability and moisture retention, essential for application-specific requirements. Indentation indices highlighted the trade-off between softness and durability, with mixed tannin-treated samples achieving balanced profiles suitable for flexible and load bearing uses. Apparent density measurements reflected structural integrity differences correlating with mechanical and absorption properties. These findings confirm that tailored combinations of indigenous tannins can optimize leather quality by enhancing mechanical strength, thermal stability, and moisture management. This work provides a scientific basis for developing advanced tanning formulations targeting improved sustainability and functional performance.

OPTIMIZATION OF TANNIN-BASED TANNING CONDITIONS USING RESPONSE SURFACE METHODOLOGY FOR IMPROVED LEATHER QUALITY

Y. M. Bammai, C. E. Gimba, K. I. Omoniyi, I. Akawu — Mon, 30 Jun 2025 00:00:00 +0000

This study investigates the optimization of tannin-based leather tanning using Response Surface Methodology (RSM) to improve leather quality parameters. A Central Composite Design (CCD) was employed to model the effects of four independent variables—tannin concentration, pH, water content, and tanning time—on key leather performance metrics such as shrinkage temperature, tensile strength, and water vapor permeability. Goat skins were treated with tannins extracted from Acacia nilotica and Caesalpinia coriaria, both individually and in combination. The statistical models revealed significant interaction and quadratic effects among the variables, with tannin concentration and tanning time exerting the most substantial influence on leather performance. Optimal tanning conditions were achieved at approximately 27.5% tannin concentration, pH 5.5, 95% water content, and 80 minutes of tanning time. These conditions resulted in leather with superior shrinkage temperatures (up to 99?°C), tensile strength (38.52 MPa), and acceptable water vapor permeability. The study highlights the synergistic potential of combining hydrolysable and condensed tannins and supports the viability of indigenous plant-based tannins as eco-friendly alternatives to synthetic tanning agents, particularly chromium salts. The findings advocate sustainable leather production practices aligned with circular economy principles and local resource utilization.