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The present study aimed to assess the effects of raw (RGNH), ethanol-extracted (EEGNH), and acid-treated (ATGNH) groundnut (Arachis hypogaea L.) husk for removal of chromium from tannery effluent from the Mojo tannery industry, Ethiopia. The effects of biosorbent dose, agitation speed, and contact time of heavy metal on biosorbent were measured. The percentage removal of chromium was examined by a flame atomic absorption spectrophotometer (FAAS). Functional group characteristics of the biosorbents were analyzed using Fourier transform infrared spectra (FTIR). The results indicated that at low doses (2 g), acid-treated groundnut husk (ATGNH) exhibited the highest removal efficiency (89.93%), whereas at a high dose (4 g), the raw groundnut husk (RGNH) has a potential removal efficiency (91.03%). The least removal efficiency was displayed by ethanol-extracted groundnut husk (EEGNH) (65.43%) at a dose of 3 g. Relating to the contact time, the highest chromium removal (94.41%) was exhibited by ATGNH with a 1-hour contact time. However, as contact time increased from 2 to 4 hours, there was a general decrease in the efficiency of biosorption. The removal of chromium by RGNH and EEGNH increased as contact time increased from 1 to 3 hours. The highest chromium removal (90.02%) was observed with ATGNH at 160 rpm agitation speed. [ABSTRACT FROM AUTHOR]

In order to better grasp the development and trends of tannery wastewater (TWW) treatment research, this paper provides a review of the TWW treatment research dynamics based on the Web of Science (WoS) database and using CiteSpace software. The research dynamics, hot topics, evolutionary history and research trends in this field are revealed. The results showed that research related to TWW treatment has shown a high growth trend in the number of articles in recent years, and India was outstanding in terms of influence in this area. The keyword clustering analysis showed that the main research hotspots in the field of TWW treatment were biological treatment processes (phytoremediation, constructed wetlands, anaerobic treatment and biofilm reactors) and chemical treatment processes (coagulation and flocculation, and advanced oxidation processes). The analysis of new research frontiers showed that the bioremediation and the application of biofuel cells in TWW will become important research directions in the future. [ABSTRACT FROM AUTHOR]

Leather industry is the second largest export-earning sector of Pakistan. However, because of poor waste management, this industry has been continuously polluting the environment. In this paper, the impact of tanneries on the groundwater quality of Kasur city (i.e., the second largest leather producing city) is examined. The study is conducted in the following three phases: (I) water samples collection, (II) determination of physio-chemical properties, and (III) application of data mining techniques. In phase I, groundwater samples were collected from various sources such as hand pumps, motor pumps, and tube wells. In phase II, several physio-chemical properties such as (i) total dissolved solids (TDS), (ii) pH, (iii) turbidity, (iv) electrical conductivity (EC), (v) total hardness (TH), (vi) total alkalinity (TA), (vii) nitrates, (viii) chromium, (ix) fluoride, and (x) chloride were estimated. The estimated values of all these foregoing parameters are then compared with the Punjab Environmental Quality Standards for Drinking Water (PEQSDW). In phase III, principle component analysis and cluster analysis of the estimated parameters were performed to elucidate the relation between various parameters and to highlight the highly vulnerable sites, respectively. The results exhibit that most of the sampling collections sites are at the threshold of losing quality water. Moreover, it is also found that Mangal Mandi carries the worst groundwater quality among all sampling locations. Overall, it is concluded that serious attention is due from the water and wastewater authorities to further investigate and monitor the groundwater quality of Kasur before the country strikes with another pandemic after COVID-19. [ABSTRACT FROM AUTHOR]

Tannery sludge is disposed of in landfills as it is considered a special residue by the Italian legislation, creating pollution and waste. This paper aims at evaluating the performance of the anaerobic fermentation process to obtain short-chain fatty acids (SCFAs) from this waste. The assessment of the most appropriate conditions, in terms of pH, temperature, initial total solids (TSs) content, and application of oxidizing-thermal pretreatment has been developed. The batch test trials revealed that the combined microwave and hydrogen peroxide (MW-H2O2) pretreatment followed by thermophilic conditions gave the best results, in terms of the acidification yield (0.31 gCODSCFA/gVS0) and maximal SCFA concentration (above 26 g CODSCFA/L). In the tests conducted without pretreatment, the mesophilic temperature should be preferred since the acidification performances were comparable to or even better than their thermophilic counterparts. The SCFA composition analysis showed that in mesophilic fermentation, tannery sludge can generate up to 50% acetic acid (CODAc/CODSCFA), if previously pretreated (MW-H2O2). This research acts as a forerunner for the appropriate handling of this resource, to employ it for the development of a new tannery industry focused on a circular approach, rather than to simply dispose of it in landfills. [ABSTRACT FROM AUTHOR]

In this study, we investigated the effect of irrigation with heavy metal loaded tannery effluent on Ocimum basilicum L., an important aromatic crop for utilization of tannery wastewater and remediation of chromium rich tannery affected soils. The soil was irrigated with three different dilutions of tannery wastewater viz. 50%, 75% and 100% of tannery effluents (T, UD and U) including control. The maximum herbal biomass (105.17 g plant−1) was found in UD100. Although oil quality was not affected by application of tannery effluents, the oil yield was decreased significantly, as compared to control, in all treatments except in UD75. The chromium concentration in different plant parts was in order of root > shoot > leaf. This indicates O. basilicum is an effective aromatic crop for remediation of tannery affected sites without any effect on crop growth, oil yield per unit area and oil quality and increase in soil fertility. [ABSTRACT FROM AUTHOR]

Worldwide, tannery sludge management has become a big challenge due to containing heavy metals, especially chromium. In this study, phytoextraction of heavy metals from tannery sludge by Napier grass (Pennisetum purpureum) is presented. Heavy metals‐chromium (Cr), copper (Cu), zinc (Zn), and lead (Pb) in tannery sludge were found at 12686, 371, 265, and 66 mg/kg, respectively. Separately, Napier grass was harvested on raw tannery sludge and garden soil and examined for 16 and 20 weeks after the sowing of seeds. Metal extraction from tannery sludge in Napier grass was found in a series of Cr > Zn > Cu > Pb; the most accumulation was reported in shoot parts of plants in the order of shoots > roots > leaves. Accumulation of Cr in Napier grass at 16 and 20 weeks was 37% and 66%, respectively. An increasing trend of heavy metal gathering in the plant was found significantly by extending the harvesting period from 16 to 20 weeks. Translocation of Cr and Pb was greater than unity (1.623 and 1.339) indicating the suitability of phytoextraction. Further, Napier grass is a rapid‐yielding tropical grass, which showed a high degree of growth tolerance that could be used for treating heavy metals contaminated tannery sludge. [ABSTRACT FROM AUTHOR]

Recent research has demonstrated that hybrid linear flow channel reactors (HLFCRs) can desulfurize tannery effluent via sulfate reduction and concurrent oxidation of sulfide to elemental sulfur. The reactors can be used to pre-treat tannery effluent to improve the efficiency of downstream anaerobic digestion and recover sulfur. This study was conducted to gain insight into the bacterial communities in HLFCRs operated in series and identify structure-function relationships. This was accomplished by interpreting the results obtained from amplicon sequencing of the 16S rRNA gene and quantification of the dissimilatory sulfite reducing (dsrB) gene. In an effort to provide a suitable inoculum, microbial consortia were harvested from saline estuaries and enriched. However, it was found that bioaugmentation was not necessary because native communities from tannery wastewater were selected over exogenous communities from the enriched consortia. Overall, Dethiosulfovibrio sp. and Petrimonas sp. were strongly selected (maximum relative abundances of 29% and 26%, respectively), while Desulfobacterium autotrophicum (57%), and Desulfobacter halotolerans (27%) dominated the sulfate reducing bacteria. The presence of elemental sulfur reducing genera such as Dethiosulfovibrio and Petrimonas is not desirable in HLFCRs, and strategies to counter their selection need to be considered to ensure efficiency of these systems for pre-treatment of tannery effluent. [ABSTRACT FROM AUTHOR]

The adsorption process is an effective method for wastewater treatment for the removal of various types of pollutants. Numerous agro-industrial and domestic waste products have been used to create affordable adsorbents. Waste materials can be used as inexpensive adsorbents, which is appealing because it lowers the cost of waste disposal and helps to protect the environment. Therefore, this research aims to valorize the solid wastes produced during the tanning process. The accumulation of solid waste in tanneries is an environmental problem in many countries. This problem can be alleviated by optimizing the use of these pollutants. Chrome and white shavings were used (as adsorbent) for the treatment of industrial wastewater. The wastewater was collected from the chemicals and resin production factory. White shavings were pretreated before use. The functional groups located on the surface of the pretreated white shavings were investigated using the Fourier-transform infrared spectroscopy technique. The treated white shavings were ground to suitable grain size (0.5-1 mm). The treatment scheme consisted of settling (1 h), sand filtration (0.5-1.0 mm), and adsorption with the pretreated ground chrome and white shaving used for the treatment of wastewater. The influent chemical oxygen demand and biochemical oxygen demand were reduced from 8,025 to 890 and from 2,808.75 to 489.5 mg/L. The effluent met all national regulatory standards for sewer system discharge. Consequently, chrome and white shaving could be used as adsorbents for the treatment of industrial wastewater. These materials could be used as preferable adsorbents for the treatment of wastewater several times. [ABSTRACT FROM AUTHOR]

Most current methodologies for the treatment of tannery effluents do not succeed in bringing contaminant levels down to values that fit environmental standards in force, which means there is a need for appropriate optimization. The present work assessed effluent quality to gain further insight into their variability across time, considering both conventional parameters and those specifically related to tannery effluents, such as chromium levels. Most of the effluents analyzed exceeded the contaminant limits established by current national legislation and therefore would require treatment. To improve treatment efficiency, a mixed bacterial culture was selected on the basis of its ability to remove organic matter (OM), measured in terms of chemical oxygen demand (COD) and biochemical oxygen demand (BOD5). The four strains analyzed, belonging to the genera Bacillus, Rhodococcus and Acinetobacter, were isolated from sediments contaminated with effluents with a high organic load. The native consortium SFC 500-1, formed by Acinetobacter guillouiae SFC 500-1 A and Bacillus toyonensis SFC 500-1E, proved to be the most effective at reducing BOD5 and COD. It was selected for bioaugmentation treatment. Dissolved oxygen was found to be key for reduction, and the inoculum size required to treat effluents with different COD values was also determined. All in all, the results confirmed previous characterization of these effluents, which should always be the basis for treatment and management strategies, and also contributed to optimizing some operational parameters so that effective and safe treatment technologies may be developed. [ABSTRACT FROM AUTHOR]

Wastewater from tanneries is a major source of heavy metals in soil and plants when used for crop irrigation. The unavoidable toxicological effects of this contamination, however, can be minimized through two independent steps discussed in the present study. In the first step, a batch sorption experiment was conducted in which Cr was adsorbed through bentonite clay. For this purpose, DTPA extraction method was used to analyze Cr concentration in the soil after regular time intervals (0.5, 1, 2, 6, 8, 9, 10.5, 11.5, and 20.3 h) which reduced Cr concentration from 38.542 mgL-1 for 30 min to 5.6597 mgL-1 for 20.3 h, respectively, by applying 1% bentonite. An increase in the contact time efficiently allowed soil adsorbent to adsorb maximum Cr from soil samples. In the second step, a pot experiment was conducted with 10 different treatments to improve the physiological and biochemical parameters of the Solanum melongena L. irrigated under tanneries' wastewater stress. There were four replicates, and the crop was harvested after 30 days of germination. It was seen that the application of wastewater significantly (P < 0.01) reduced growth of Solanum melongena L. by reducing root (77%) and shoot (63%) fresh weight when compared with CFOP (Ce-doped Fe2O3 nanoparticles); chlorophyll a and b (fourfolds) were improved under CFOP application relative to control (CN). However, the deleterious effects of Cr (86%) and Pb (90%) were significantly decreased in shoot through CFOP application relative to CN. Moreover, oxidative damage induced by the tannery's wastewater stress (P < 0.01) was tolerated by applying different soil amendments. However, results were well pronounced with the application of CFOP which competitively decreased the concentrations of MDA (95%), H2O2 (89%), and CMP (85%) by efficiently triggering the activities of antioxidant defense mechanisms such as APX (threefold), CAT (twofold), and phenolics (75%) in stem relative to CN. Consequently, all the applied amendments (BN, BT, FOP, and CFOP) have shown the ability to efficiently tolerate the tannery's wastewater stress; results were more pronounced with the addition of CFOP and FOP+BT by improving physiological and biochemical parameters of Solanum melongena L. in an eco-friendly way. [ABSTRACT FROM AUTHOR]

The current investigation focuses on a systematic study of application of two dried algal biomass (i.e., Nostoc sp. and Turbinaria vulgaris) in removal of Cr(VI) from synthetic solution as well as tannery industrial wastewater. The optimized conditions for Cr(VI) removal are nearly same for the both the biosorbents (i.e., pH 2.8, initial Cr(VI) concentration 100 mg L−1, biomass dosage of 1.2g L−1, contact time 120 and 110 min). Nostoc sp. (qmax=23.94mg g−1) was observed to possess a superior removal capability when compared to Turbinaria vulgaris (qmax=21.8mg g−1). Desorption studies were performed with four different desorbing agents. Application study was conducted using tannery wastewater with Nostoc sp. and 94.20% removal of Cr(VI) was obtained. Hence, this study revealed that Nostoc sp. and T. vulgaris both have great potential to be an environment friendly and economic biosorbent for removal of Cr(VI) containing industrial effluent. [ABSTRACT FROM AUTHOR]

Adsorption is one of the best methods for removing metals from aqueous medium. In the present study, bentonite clay was used as an adsorbent for heavy metal Cr+6 removal from the synthetic solution as well as actual waste water collected from local tanneries. Bentonite was used with and without chemical modification to improve removal efficiency. The adsorbent was modified with HCl, H2SO4 and NaOH. The batch adsorption technique was applied to study the effect of pH, initial concentration of metal ions, adsorbent dose and shaking time on the adsorption process. The chemical oxygen demand and biological oxygen demand of tannery effluents were significantly reduced upto 77.6% and 81.2%, respectively. The original bentonite clay removed upto 59%, while 98% removal was achieved with H2SO4 modified bentonite clay, 68% with HCl modified clay and 89% by NaOH-modified clay. Furthermore, the percentage removal efficiency was reduced by increasing the initial concentration of metal ions. The current study concluded that bentonite clay is a good adsorbent and modifications to bentonite clay can effectively improve the physical characteristics of the clay to adsorb Cr+6 ions. Moreover, bentonite clay is inexpensive and readily available in our country. [ABSTRACT FROM AUTHOR]

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 SFRwas significantly desorbed fromthe 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 pHZC 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. [ABSTRACT FROM AUTHOR]

Synergistic effect of biochar and microbes in soil enhances performance of plants. Hazardous tannery solid waste can be reduced by one-third in volume by conversion to biochar. A greenhouse trial was set up with soil having different doses of metal resistant microbe-impregnated biochar (MIBC) prepared from tannery solid waste. Consortia of autochthonous strains of Trichoderma and Bacillus were inoculated on BC and the behavior and fate of metals were evaluated for their bioavailability to sunflower. Sunflower was grown in pots for 80 days having six different amendments of tannery solid waste biochar (0–10% w/w) with and without Trichoderma and Bacillus consortia and its morphological and biochemical attributes as well as metal uptake were observed. The results illustrated that application of BC at 2% rate without inoculation increased the shoot length and dry biomass by 19.8% and 77.4%, respectively, while plant growth and performance were reduced at higher amendments of BC. However, application of MIBC with Trichoderma or/and Bacillus consortium significantly improved the plant attributes at all levels of amendment. The results indicated that MIBC having Trichoderma and Bacillus consortia at 10% rate increased shoot length and dry biomass by 65.3% and 516% compared to control without BC. Application of BC without inoculation reduced the uptake of Cu, Fe, and Ni and increased the mobilization of all other metals for uptake in sunflower. Mobilization and uptake of Cd, Cr, Cu, Ni, Pb, and Zn decreased with MIBC having Trichoderma and Bacillus consortia whereas that of Fe and Mg were noted. A considerable decrease in proline and total phenolic content was demonstrated by MIBC-grown sunflower. The data of metal fractionation in BC also supported the above findings. Therefore, MIBC can be used as a promising option for enhancing growth performance and ensuring the physiological safety of sunflower as an energy crop. [ABSTRACT FROM AUTHOR]

Heavy metals pollution of water and soil caused by industrial activities has become a prominent environmental concern in Pakistan. Thus, it is important to examine the contaminants concentration in water and soil close to the industrial areas. In this study, we have evaluated the different heavy metals contamination in groundwater and soil at tannery areas of three large cities of Pakistan, Lahore, Karachi and Sialkot. Groundwater and soil samples collected from Lahore, Karachi and Sialkot tannery areas and examined for chromium, iron, nickel, cadmium, lead, copper, and manganese by atomic absorption spectrometer. The results presented that groundwater and soil in the Lahore, Karachi, and Sialkot are highly contaminated with several heavy metals. Particularly, the concentration of chromium varied from 0.41 to 1.107 mg L-1 in Lahore, 0.35 to 2.209 mg L-1 in Karachi and 0.31 to 2.29 mg L-1 in Sialkot and from 1,731 to 2,554 mg kg-1 in Lahore, from 1,676 to 3,018 mg kg-1 in Karachi and from 1,793 to 3,274 mg kg-1 in Sialkot in groundwater and soil, respectively. Correlation exploration has recognised that metals in soil and groundwater of study areas having common origin/source, believed to be leather processing industries of Lahore, Karachi and Sialkot. [ABSTRACT FROM AUTHOR]

Bioleaching of tannery sludge is an efficient and environmentally friendly way for chromium (Cr) removal, which supports the sustainable development of the leather industry. Acidithiobacillus thiooxidans has been reported effective in Cr bioleaching of tannery sludge. However, little is known about whether the presence of other benefiting species could further improve the Cr leaching efficiency of A. thiooxidans. Here, we studied the enhancing roles of four species namely Acidiphilium cryptum, Sulfobacillus acidophilus, Alicyclobacillus cycloheptanicus, and Rhodotorula mucilaginosa in chromium bioleaching of tannery sludge with A. thiooxidans by batch bioleaching experiments. We found that each of the four species facilitated the quick dominance of A. thiooxidans in the bioleaching process and significantly improved the bioleaching performance including bioleaching rate and efficiency. The bioleaching efficiency of Cr in the tannery sludge could reach 100% on the sixth day by co-inoculating A. thiooxidans and four auxiliary species. The achievements shed a light on the role of the community-level interactions on bioleaching and may also serve as guidance for managing bioleaching consortiums for better outcomes. [ABSTRACT FROM AUTHOR]

Louis Pasteur was born in Dole on December 27, 1822. The Pasteur family left the town of Dole in August 1825. After five years in Marnoz, Jean-Joseph Pasteur rented a tannery in Arbois in 1830. In the 1831 register of house visits, he is mentioned at 83 rue de Courcelles: "Pasteur Jean-Joseph, tanner, age 39, from Besançon. Jeanne Etiennette Roqui his wife, 37 years old, from Marnoz 4 children: Jeanne-Antoine 11 years old. Louis 9 years old. Joséphine 5 years old. Emilie 3 years old. A worker, Eloy Dole, 25 years old, from Poligny". At that time, Arbois and its suburbs had nearly 7000 inhabitants. The young Pasteur first attended the mutual education school and then the municipal college. After failing in Paris in 1838 to prepare for the baccalaureate, Pasteur studied rhetoric in Arbois and then, in 1839, at the royal college in Besançon. In 1842, Pasteur entered the École normale supérieure. In 1849 he became a professor at the faculty of Strasbourg, 1854 professor and dean of the new faculty of sciences of Lille, 1857 Pasteur was at the Ecole normale supérieure as administrator and director of scientific studies. In spite of his high functions, Pasteur and his family always came back to Arbois, it was a return to their roots. "If there is no Arbois, there is no Pasteur," said the writer and academician Erik Orsenna. [ABSTRACT FROM AUTHOR]

This review focuses on the technique known by the name of cavitation for wastewater treatment. There are several ways to make a fluid cavitate; the focus of this document is hydrodynamic cavitation and acoustic cavitation. Cavitation occurs when a fluid abruptly changes phase due to a variation in its pressure: the cavities have a considerable amount of energy that favors reactions inside and at the interface of each bubble or cavity that forms within the liquid, as well as in the fluid. This treatment technique is favorable since does not imply the use or dosage of chemical inputs to reduce the concentration of contaminants in the water. The sources consulted indicate that to achieve greater effectiveness of the cavitation process, it is necessary to intensify the process by the simultaneous implementation of other treatment techniques, including advanced oxidation processes, electrochemical processes, and water clarification. The combinations of cavitation with other wastewater treatment techniques have been studied for different recalcitrant pollutants, achieving very favorable results. This work is mainly focused on wastewater from tanneries. [ABSTRACT FROM AUTHOR]

Experiments were carried out to isolate Hexavalent chromium reducing bacterial cultures (Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa) from the sludge of leather industry collected from Ranipet industrial area and its ability to reduce hexavalent chromium to trivalent chromium was performed. Different parameters such as inoculum volume, optimum temperature, medium, and pH were studied for efficient reduction of chromium (VI) by using the isolated organisms. The isolates were tested for the tolerance to different heavy metals; the three isolates were subjected to antibiotic sensitivity test and Minimum Inhibitory Concentration test. [ABSTRACT FROM AUTHOR]

Tanneries produce large amounts of wastewater with high concentrations of suspended solids, organic matter, and salts. Treatment and reuse of these effluents are of great importance to preserve water resources and save costs. Although suspended solids and high percentages of organic matter can be eliminated by physico-chemical and biological processes, refractory chemical oxygen demand (COD) and salts will remain in the wastewater after these processes. In particular, chloride and sulphate ion concentrations may hinder the treated wastewater from being reused or even discharged according to legal standards. In this work, two nanofiltration membranes and two reverse osmosis membranes are tested to assess these technologies as regeneration processes for biologically treated tannery wastewater. Permeate flux and rejection of organic matter and ions were measured at different operating conditions (transmembrane pressure and cross-flow velocities) at both total recycle and concentration modes. Results showed that the difference between permeate fluxes of nanofiltration (NF) membranes and reverse osmosis (RO) membranes was very high. Thus, at 20 bar and 1.77 m·s−1, the permeate flux of the two tested NF membranes in the total recycle mode experiments were 106 and 67 L·m−2·h−1, while the obtained permeate fluxes for the RO membranes were 25 and 18 L·m−2·h−1. Concerning rejections, RO membranes rejected almost 100% of the salts, whereas NF membranes reduced their rejection when faced with increasing concentration factors (salt rejection between 50–60% at the highest concentration factor). In addition, the fouling of RO membranes was lower than that of NF membranes, recovering more than 90% of initial permeability by only water rinsing. In contrast, chemical cleaning was necessary to increase the permeability recovery of the NF membranes above 90%. The considerably lower rejections and the higher membrane fouling of the NF membranes lead us to conclude that reverse osmosis could be the most feasible technique for water reuse in the tannery industry, though the permeate fluxes are lower than those achieved with NF membranes. [ABSTRACT FROM AUTHOR]

The increased population has led to an increase in the demand for goods which results in rapid industrialization. Demands for goods are directly proportional to the number of industries. In turn, the increase in industrial set-ups has led to the increased production of industrial wastes. These industrial wastes cause major environmental havoc by polluting the water air and soil. In this paper we will discuss about the load of industrial waste and its effect on the Kanpur city by disposal of pollutants. As we know Kanpur city has nearly 800 industries. The city of the Kanpur in the north Indian state Uttar Pradesh is famed for its leather industry, meeting national and international demands for superior quality leather. The industry, which employes thousands and earns a lot of revenue however, has a notorious side to it. It is a source of hazardous Pollution that environmentalists say, is gradually killing the city. Each day, the tanneries pump out about 30 Crore litres of polluted water into adjucent, Ganges river. While city's water treatment unit has a capacity of treating 17 crore litres per day, Kanpur also generates 400 tones of solid waste water pollution through the discharge of industrial effluents is causing severe problems. The pollutants include As, Cr, Cd, Cu, Fe, Hg, Pb and Zn which are considered as toxicants. This research article presents a review on the toxicity of chromium and its health hazards on living organism based on the previous research is done. [ABSTRACT FROM AUTHOR]

Chromium (III) salts are highly applied for tanning purpose in tannery industries. The purpose of this study was removal and recovery of chromium(III) from tannery wastewater with a strong cation exchange resin. For this purpose, Amberlite 252 ZU was chosen as a strong cation exchange resin. In the first part of this study, The MINEQL+ computer program was applied depending on the optimum concentration and pH for determining Cr species in aqueous solutions. The second part of the work consists of measuring the exchange equilibrium of H+ ions and Cr(III) ions. Therefore, solutions containing fixed amounts of chromium were brought into contact with different amounts of resins. The evaluation of the obtained equilibrium parameters was done by surface complexing theory. Retention and regeneration steps were successfully performed in the column without any significant change up to 10 cycles. Efficiency was between 90 and 98% in removal studies, and between 81 and 92% in recovery studies. The results showed that a strong cation exchange resin Amberlite 252 ZU can be successfully used for chromium removal and recovery. [ABSTRACT FROM AUTHOR]

Background: The tannery industry is a potent environment polluting agent worldwide. Chromium (VI) is a major heavy metal in tannery effluents and their accumulation in soil and water is a serious environmental problem. This study investigates the capacity of indigenous bacteria isolated from tannery effluents for tolerance to chromium (VI). Methods: The chromium tolerance of isolates assessed through both agar dilution and broth microdilution methods. Isolates were identified by morphological and biochemical analysis. The tolerance of isolates to cadmium, nickel, lead, and vanadium and also their multidrug-resistant (MDR) profile were determined. Then the top isolate was characterized via 16S rRNA sequencing and its growth temperature and pH were optimized. Finally, the kinetic of chromium biosorption and chromium removal efficiency was determined using a Nutrient broth medium and wastewater containing 20 mg/L chromium, respectively. Results: Of 32 screened chromium tolerant isolates, 14 isolates with higher chromium tolerance were selected for further study. 78.57% of isolates represented simultaneous MDR and Multi Heavy Metal tolerance (MHMT) phenotypes and MDR indices of 0.2–1 indicating their source from niches with high antibiotic contamination. However, there was no significant correlation between MDR and MHMT phenotypes among isolates. The top isolate was identified as Lactococcus lactis and showed optimal growth at pH 6 and 25 °C. The maximum chromium biosorption occurred at the end of the exponential phase upon optimized conditions and the approximate chromium removal efficiency of 52.5% was obtained. Conclusion: The isolated bacteria specifically L. lactis after more evaluations, may show the potential for bioremediation of chromium from tannery effluents. [ABSTRACT FROM AUTHOR]

The article focuses on the relationship between human smell and the historical past through what the authors call, "Whiffstory." The authors use a portrait of the Ulm patrician Helena Schermar in the Museum Ulm, attempt to recreate the Early Modern scent of her white leather gloves, and use this as an olfactory interpretation.

The adsorption of methylene blue (MB) was investigated using the prepared activated carbon (AC); obtained by the chemical activation of chrome shaving dust (CSD). Results represented that the increase of particle size and impregnation ratio of AC possessed a proportional effect on the adsorption of MB. AC produced by H3PO3, impregnation ratio of 1:6, and mesh size of 40 showed the highest adsorption performance. The removal of other organic and inorganic pollutants from different tannery effluent was found satisfactory like pH, conductivity, turbidity, BOD5, COD, and Cl- values are reduced to 5.5-8.48, 73-93%, 76-92%, 80-96%, 71-87% and 84-94%, respectively which are nearly closed to the WHO's standards for industrial effluent to the environment. The microscopic analysis confirmed the smooth and porous surface characteristics of the adsorbent. Hence, CSDAC can be expected to become an effective, low-cost, and suitable adsorbent for both dye and pollutants removal from industrial wastewater. [ABSTRACT FROM AUTHOR]

The protein hydrolysates were prepared by the thermal-alkaline treatment of tannery sludges, and then the proteins of tannery sludge were successfully extracted by the acidification method. The results showed that the extraction rate of sludge proteins increased and then decreased with the increase of NaOH dosage, time and temperature. The optimum temperature, time and NaOH dosage for extracting sludge proteins were 150 °C, 60 min and 9 g/L respectively, resulting in the highest extraction rate of 71. 2%. The interaction o£ temperature, temperature and time is the most important factor to affect the extraction rate o£ sludge proteins. The purity, total chromium concentration, common amino acid content of extracted tannery sludge proteins is 83. 01%, 1.5 mg/kg and 31. 09%, respectively. In addition, the sludge proteins have a low content of inorganic salts and ashes. The molecular weight of tannery sludge proteins ranges from 5 to 35 kDa. [ABSTRACT FROM AUTHOR]

The tannery industry is characterized by the consumption of a large quantity of water, around 30–40 m3 for processing 1000 kg of hide or skin. This amount becomes wastewater, containing about 300 kg of different chemicals, mainly refractory organic compounds, with high chemical oxygen demand (COD), total dissolved salts (TDS), chromium, and evolution of toxic gases, such as ammonia and sulfides, etc. The remaining tanning chemicals are released as effluent having high resistance against biological degradation, becoming a serious environmental issue. Usually, end-of-pipe treatment is not sufficient to meet the concerns of environmental issues. In terms of cleaner production options, the redesigning of the existing effluent treatment procedures with alternate or additional treatment techniques, which "supports resource recovery with no added chemicals", is expected to give a sustainable solution for the management of toxic effluent. The Zero Liquid Discharge (ZLD) system serves to ensure zero water emission, as well as treatment facilities by recycling, recovery, and reuse of the treated wastewater using advanced cleanup technology. The international scenario shows the implementation of ZLD thanks to pressure from regulatory agencies. The ZLD system consists of a pre-treatment system with conventional physicochemical treatment, tertiary treatment, softening of the treated effluent, reverse osmosis (RO) treatment for desalination, and thermal evaporation of the saline reject from RO to separate the salts. By adopting this system, water consumption is reduced. Moreover, ZLD also becomes effective in disaster mitigation in areas where the tannery industry is a strong economic actor. With this review, we aim to give an outlook of the current framework. [ABSTRACT FROM AUTHOR]

This study was conducted to characterize Marrakech City (Morocco) tanneries effluents. The analysis of 5 different tanneries recipes revealed identical temperatures (25°C), acidic pH ranging from 2.69 to 3.65, electrical conductivity ranging from 40.33 ± 1.21 to 90.43 ± 2.40 mS/cm, high chemical oxygen demand (COD: 939.33 ± 26.46 - 7,739.55 ± 297.68 mgO2/L), biological oxygen demand (BOD: 24-42 mgO2/L). In addition, there were high quantities of total suspended solids of about 6,400 ± 100 - 15,700 ± 200 mg/L, total dissolved solids (TDS: 22,566.67 ± 57.74 - 50,900 ± 100 mg/L), total solids (TS: 28,966.67 ± 57.74 - 66,600 ± 264.58 mg/L), sulfate (SO4 2-: 1,021.43 ± 61.86 - 2,9 50 ± 35.71 mg/L). High concentrations of total chromium ranging from 200 to 500 mg/L and Cr6+ from 117.22 ± 20.19 to 393.37 ± 42.74 mg/L were recorded. Different size and shape of effluents particles and filaments influence the sedimentation speed and scour velocity, as well as the pollutants adsorption. These results indicate that tanneries effluents are polluted, and the physico-chemical characteristics vary from one to another one. This approach could be useful as a decision-making tool for the implementation of a depollution process adapted to the local socio-economic context. [ABSTRACT FROM AUTHOR]

The fat extracted from tannery sludge was utilized for producing biodiesel by transesterification reaction using a short chain alcohol and a nano-catalyst (Fe3O4/BaO). This catalyst was synthesized through co-precipitation method and various characterization techniques were followed using analytical instruments. The synthesized catalyst was examined through transesterification reaction using tannery sludge fat for observing the activity performance. The effect of various process parameters was investigated to obtain an optimum yield of 97.6%. The optimum reaction conditions were 18:1 molar ratio of methanol/oil, 8 wt% of catalyst loading with 65 °C of reaction temperature, 300 min of reaction time and a rate of stirring of 450 rpm. Furthermore, the ASTM standard test methods were followed for examining the fuel property of biodiesel and were found to be within the range of ASTM D6751 standard. Moreover, the rate of reaction (k') was determined by conducting the kinetic studies. The obtained values of 46.64 kJ mol−1 and 21.3 × 103 min−1, respectively, denote activation energy and frequency factor. [ABSTRACT FROM AUTHOR]

The residual coloring agents present in tannery wastewater degrades the quality of ecosystem and limits photosynthetic activity in aquatic biosphere apart from causing displeasing appearance. This study is conducted to test the ability of protein coagulant extracted from Moringa oleifera (MO) seeds for removing the color from tannery wastewater. Different salt solutions such as NaCl, KCl, MgCl2 and NH4Cl were used individually to extract the coagulant from MO seeds. The color removal efficiency was the highest for NaCl extracted coagulant (75.14%) and least for MgCl2 extracted coagulant (62.38%). The coagulant extracted for 30 min duration and stored for one day at 278 K removed 75.14% coloring agents from wastewater. The efficiency of NaCl-extracted coagulant was investigated by varying the parameters such as NaCl concentration (0.1 N–0.4 N), initial pH (3–10), coagulant dose (10 mL–50 mL) and coagulant storage temperature (278 K–298K). The differential method of analyzing kinetic data indicates that process obeys second order mechanism because a plot between the rate of change in color intensity and square of the fraction of residual color is a parabolic curve. The interrelationship between response and process variables was studied using linear, exponential, logarithmic, second order polynomial and power law models. Highest color removal of 75.14% was achieved at optimal conditions of 0.2 N NaCl solution, pH 8, 40 mL dose and 278 K storage temperature. It was ascertained that the power law model (R2 = 0.906) truly reflected the system behavior, while the linear model (R2 = 0.797) had poor prediction capability. [ABSTRACT FROM AUTHOR]

The aim of the study was to determine the composition of wastewater generated in a small tannery plant in the Podlaskie Province at different stages of the technological process. Since the plant uses chromium salts for the actual tanning process and the resulting wastewater is separated into two streams, it was possible to determine the content of chromium and other pollutants in the wastewater at different stages of the production processes. This allowed us to evaluate the biodegradability of the wastewater produced during production, the concentration of chromium compounds and other contaminants. Based on the results obtained, the wastewater generated during the production process was found to be non-biodegradable (except for the mixed wastewater) with chromium concentrations of 2.0-2.46 g/dm³. [ABSTRACT FROM AUTHOR]

Owing to containing high fraction of organic matter, the tannery sludge seemed to be fit for composting. Actually, it was intensively harmful to the environment, due to containing chromium (Cr). So it might undergo a long time of storage until finding a proper way to dispose it. In the storage period, it would expose the surrounding environment a risk via releasing Cr. In this study, an approach was proposed to minimize the amount of released Cr, and reveal the mechanism on immobilizing Cr. Collagen protein waste (CPW) was adopted to immobilize Cr, and it was evaluated via leaching experiment. The lowest leaching concentration of Cr was 12 mg/L, meeting the limits of related standard in China (GB 5085.3–2007, Tcr < 15 mg/L). Moreover, the compositions and functional groups of the optimum sample (12 mg/L) were also characterized, confirming that the dominant functional groups cross-linking with Cr were hydroxyl (-OH), carboxyl (-COOH), and epoxy (-COC). Importantly, density functional theory (DFT) calculation was also employed, suggesting that Cr was restrained by accepting electrons from O atoms donating by functional groups. [ABSTRACT FROM AUTHOR]

Industrial effluents have a serious problem on our ecosystem. Tannery effluent contains a huge amount of pollutant compounds such as toxic substances which need to be treated using either synthetic or natural products. The present study focussed on the treatment of tannery effluents using water hyacinth plant leaf extract. Though some researchers have tried to use this extract for the same, the researchers have experimented only to treat that of Cr3+ and there are a bit of difference in the methodology they followed. In addition, the scope of this research was wider. In this study, fresh raw WH leaves were collected from around Lake Tana, Ethiopia, cleaned and made to powder and then extraction was performed using different solvents. The solvent effects were examined using the ANOVA test. The tannery wastewater was treated with the extracts and parts of the effluents were kept as a control for comparison. Treated and untreated tannery effluents were compared using standard methods such as SLC 22, SLC 8, APHA 2540C, APHA 2540D, and Hack LCK 139 to determine Cr6+, Cr3+, TDS, TSS, and TKN, respectively. The highest amount of Cr6+, Cr3+, and TKN were removed at 30% water hyacinth leaves extracted by distilled water solvent and that of the least was found at hyacinth leaves extract by ethanol solvent but by acetone in BOD and COD treatment. In addition, though it was out of the permissible limit, by using the same amount of the material extracted by distilled water solvent some amounts of BOD and TDS were removed from the wastes compared to that of untreated tannery effluents. Generally, water hyacinth leaf extract is found effective material for the treatment of tannery effluents and can be used in the sector industries. Future studies may be required for setting the most optimum extract concentration for better results. [ABSTRACT FROM AUTHOR]

Discharge of heavy metals from industrial complexes especially tanneries has considerably increased the levels of heavy metals in water and soil worldwide. This work was aimed to determine the levels of heavy metal (As, Cd, Cr, Cu, Ni, Pb and Zn) contamination of surface water, groundwater and soils in the site surrounding Moghan's tannery in Ardabil, Iran. Fifteen composite samples (totally 45) were collected from surface water, groundwater and soils surrounding the tannery site. In this study, the levels of metals were determined by inductively coupled plasma mass spectrometry (ICP-MS) and the results were compared to the national and international standards. The results showed that 73% of water samples from wells and 80% of samples from surface water had levels above maximum permissible levels. The levels of metals in the remaining samples were within standard values. For soil samples, the mean levels of metals, except Pb, were lower than maximum permissible levels. Among these, Cd and Zn showed the lowest and highest level, respectively. The results showed that the mean levels of chromium in surface water, groundwater and soil surrounding Moghan's tannery were high due to the pollution generated by the factory which necessitates the greater attention and implementation more pollution preventive procedures by environmental professionals and decision-makers. [ABSTRACT FROM AUTHOR]

Mismanagement of various wastes especially waste water produced by tanning processes has caused serious environmental problems and ultimately impaired human health. Constant efforts have been making to alleviate the pollution of tannery wastewater (TWW), yet terminal treatment still takes dominance. In this review, research on TWW treatment from 2000 to 2021 was summarized, and main methods such as coagulation and flocculation, adsorption, biological treatment, membrane filtration, advanced oxidation process were briefly discussed. More detailed introduction was given to the method of electrochemical treatment since it has excellent performance such as environmental friendliness and high efficiency, hence attracting more and more research attention in recent years. In view of the harsh physi-chemical conditions of TWW, integrated or combined treatment methods are accordingly recommended with better performance and multi-function, however comprehensive studies on optimization of methods combination and cost-effectiveness are needed. The certain issues that the residue Cr in treatment sludge and high salinity in effluent still remain were put forward in this work and potential solutions were provided. Moreover, this review proposed the perspective that realizing multi-function, recycling, and intensification should be the developing direction for future TWW treatment. This review is expected to provide a general guide for researchers who aspire to ameliorate TWW pollution problems and understand various methods utilized in this field. [ABSTRACT FROM AUTHOR]

Copyright of Revista Facultad de Ingeniería - UPTC is the property of Universidad Pedagogica y Tecnologica de Colombia, Facultad de Ingenieria and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The combination of carbon and nitrogen-rich co-substrates results in a better balance and increases the stability of the anaerobic co-digestion (AcoD) process. In this work, the AcoD process of waste from the leather industry (shavings and sludge) with waste from agriculture (oat straw) was assessed with regard to the energy (biogas production) and waste treatment efficiency (reduction of organic matter). The results indicate that the addition of untreated oat straw improved the AcoD process, increasing biogas production (25.44 mL of cumulative biogas/g of VSS added) by almost 60% when compared to the AcoD of only leather waste (16.17 mL/gVSS). Also, the effect of acid, alkaline, thermal, and the combination of these pretreatment techniques was evaluated on the lignocellulosic composition of oat straw and on methane yields. Pretreatments improved the characteristics and bioavailability of oat straw, particularly in methodologies that use alkali, with a significant increase in cellulose content accompanied by a decrease in hemicellulose and lignin content. However, the possible formation of secondary products or sterilization of important microorganisms did not reflect in a greater production of biogas: 21.06 mL/gVSS for oat straw pretreated only with HCl and 21.91 mL/gVSS for oat straw pretreated with HCl in autoclave; 5.20 mL/gVSS for oat straw pretreated with NaOH; and 3.43 mL/gVSS for oat straw pretreated with NaOH in autoclave; thermal pretreatment probably has generated toxic compounds from hemicellulose and cellulose degradation, which inhibited the AcoD process and, as consequence, virtually no biogas was produced. [ABSTRACT FROM AUTHOR]

Any wastewater treatment system must have a complete model to provide a tool for predicting the system's performance and to serve as the foundation for regulating the process's operation. This would save running expenses while also examining the stability of the environmental balance. This process is challenging and reaches a high degree of non-linearity due to the presence of bio-organic elements that are difficult to define using mechanistic techniques. Predicting plant operating characteristics using standard experimental approaches is time consuming and difficult, making it difficult to regulate such operations effectively. Using a radial function neural network, a research was successfully simulated to analyse the performance of sequential batch reactors on a lab scale. The information gathered is used in a neural network to treat tannery waste water in a sequential batch reactor. Degradation of organic compounds is represented in this method by a trained neural network. The degradation investigations used different dilutions such as 25%, 50%, 75%, and 100% for an initial substrate concentration of 6,240 mg COD/L and at different hydraulic retention times (5, 4, 3, and 2 d). The neural network-based model is thought to have been effective in establishing the system's properties with high precision. This research uses an artificial neural network (ANN) modelling technique to obtain the knowledge base of a genuine SBR, which is then used as a process model. [ABSTRACT FROM AUTHOR]

The sequential batch reactor (SBR) technology is being applied in a large number of treatment processes owing to the operational flexibility it offers. SBR's capability to carry flow equalization, biological processes, and secondary clarification within a single reactor by differing the time period of different phases and duration of aeration proves it a flexible process for wastewater treatment. In this study SBR was employed to treat the tannery industry wastewater for removing colour. The phase of the SBR was observed over a period of 50 d. Statistical based experiments were performed for optimizing the parameters viz., pH, temperature, inoculum's concentrations, agitation speed and initial concentration of the substrates on the treatment of wastewater from tanneries by the mixed culture derived from the tannery common effluent treatment plant sludge, in a batch reactor under aerobic condition. At the optimized conditions, experiments were performed by salt tolerant microorganisms such as Pseudomonas aeruginosa, Bacillus flexus, Exiguobacterium homiense and Staphylococcus aureus at various organic loading rate (OLR) by varying tannery wastewater concentration and hydraulic retention time (HRT) for colour removal. A maximum decolourization 94% was obtained in SBR with the OLR 0.312 kg COD/m3 d, HRT 5 d for the substrate's initial concentration of 1,560 mg COD/L. [ABSTRACT FROM AUTHOR]

The anaerobic treatment of tannery effluents from the different process stages are limited by the various toxicants that are mainly added as feed chemicals. The segregated effluents present an opportunity for co-treatment to abate inhibition, supplement deficient nutrients and/or promote resource recovery using anaerobic digestion. This study investigated the feasibility of anaerobic co-digestion of beamhouse (BH) and pre-treated tanyard (TY) effluents using the standardised biochemical methane potential (BMP) protocol. It was established that all reactors were active, while those with higher TY compositions and operating at very high/low inoculum to substrate ratios (3

Tannery sludge has great potential for use in agriculture, however it is a potentially toxic waste, and it is necessary to establish the ideal dose for each crop. The objective of this study was to evaluate the influence of fertilization with liquid tannery sludge on growth, chlorophyll a fluorescence and gas exchange of Pennisetum purpureum in two production cycles. A 2 × 6 + 1 split plot scheme was used, where the first factor was composed of two productive cycles, the second factor different fertilizations doses: 0, 30, 70, 110, 150, 190 t ha−1 of liquid tannery sludge and an additional treatment with nitrogen, phosphorus and potassium control. Plant height, number of leaves and tillers, canopy and stem diameter, leaf area, dry matter, chlorophyll index (SPAD), chlorophyll a fluorescence and gas exchange were evaluated. The highest production of total dry matter was observed in the second production cycle. The range between 72–100 t ha−1 of liquid tannery sludge showed the greatest gains in growth and production of elephant grass. At doses above 150 t ha−1 of liquid tannery sludge, the photochemical apparatus begins to show possible damage to the photosystem II (PSII) and reductions in gas exchange. [ABSTRACT FROM AUTHOR]

Emergy Accounting (EMA) has gained attention in recent times as an environmental accounting tool. So far, it has been used for analysis at national and regional levels; however, the EMA has not been utilised in a business performance analysis context. When used in a business context, EMA reveals the interface between industrial activity and the environment. EMA analysis can provide opportunities in measuring the social, economic, and environmental performance of the industry in a sustainability context. Unlike other evaluation methods, which are 'demand-side' or 'user-side' concerned, EMA analysis is a 'donor-side' approach. This research work illustrates the selection of suppliers based on the amount of emergy consumption. Emergy indicators, such as Emergy Yield Ratio (EYR), Emergy Sustainability Index (ESI), Environmental Loading Ratio (ELR), Emergy Self-support Ratio (ESR), Renewability percent (%R), Emergy flow Density (ED), and Emergy Investment Ratio (EIR) are estimated. The results show that there is enough room for improving emergy performance in the tannery industry. The result also highlights a significant variance in the input of indigenous renewable and non-renewable resources and imported resources among the investigated tanneries. Based on the outcomes, the study provides insights on the industries' consumption of renewable and non-renewable resources. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the physicochemical properties and the presence of heavy metals in groundwater samples. This study was carried out on the site of a tanneries of Vaniyambadi Taluk in the Vellore district. Evaluate the pollution index and risk assessment to assess the suitability of groundwater for human consumption. The information absorbed Physico-chemical properties and heavy metals like., Copper, Chromium, Lead, Zinc, Nickel, Aluminum, Cadmium contamination of groundwater samples. Flame AAS (Atomic Absorption Spectrometer) method used to assess the heavy metals concentration, The metal strength of groundwater in the area of the tanneries is rather high. As a result of the analysis, it was found that the chromium concentration was quite high in the groundwater samples from the tanneries, and the strengths of copper, chromium, lead, zinc, nickel, aluminum, and cadmium metals were also found slightly higher in groundwater in the tannery area. The calculated pollution indices, the Contamination Index (CI) and the Environmental risk Index (IER) for heavy metals, indicate that the majority of the groundwater samples studied are in severely contaminated areas. All physicochemical properties are within the normal range and metal contamination of groundwater is responsible for maintaining the harmfulness of crops and household needs. [ABSTRACT FROM AUTHOR]

Sodium chloride (NaCl) is commonly used as a curing/preservative agent for raw hides and skins in tanneries and is removed through a soaking process with total dissolved solids (TDS) and other organic pollutants in effluent, causing significant pollution load to the environment. Hence, the present study evaluated to apply dried neem leaf powder (DNL) as an additive to reduce the usage of salt in skin processing and preservation. To make certain of DNL antimicrobial properties, solvent extracts were performed against proteolytic bacteria isolated from raw skins. Initial characterization of DNL revealed the presence of bioactive compounds nimbolide and dehydro salannol and acetone extract with 16.9-mm, 10-mm and 8-mm zone of inhibition against Salmonella sp., E. coli sp. and Bacillus sp. identified using phenotypic conventional biochemical screening method. Further, skin curing experiments were carried out using four different treatments of DNL (10% 15%, 20% and 25% w/w) along with 15% w/w of conventional salt to obtain an optimum concentration for pilot-scale studies. Thus, the application of optimal DNL (15%) and salt (15%) resulted in no physical changes such as smell and hair slip and was taken for further studies for hydroxyproline activity, pollution load and organoleptic properties along compared with control 40% salt. DNL-aided salt less preservation of freshly flayed goat skins at ambient condition showed no hair slip or putrefaction during the preservation period with significant reduction of TDS (86%) and chloride (71%) in soak liquors compared to conventional salt preservation and enhanced organic load requiring additional treatment. However, the application of the organoleptic, physical and hydrothermal properties of resulting leathers produced from the DNL applied skins was on par with results of leather obtained from conventional salt. Thus, our results demonstrate DNL-aided salt less preservation method is able to reduce the amount of salt for preservation of goat skins significantly, leading to reduced salinity issues during leather processing. [ABSTRACT FROM AUTHOR]

In this study, biodiesel was prepared using fat from tannery waste in the presence of a nanocatalyst, Ferric-Manganese Doped Sulfated Zirconia (Fe-Mn-SO4/ZrO2). After its preparationthe catalyst was characterized by modified wetness impregnation method. The effect of the various parameters influencing the biodiesel process was studied and optimized. A maximum biodiesel yield of 96.6 wt% was obtained when the optimized conditions were 12:1 methanol to fat, catalytic loading of 6 wt% at 65°C with a stirring rate of 450 rpm for 300 min. Furthermore, a catalyst reusability study was conducted to check the performance during recycling. It was observed that the catalyst can be recycled upto five times giving an yield above 90 wt%. Finally, the biodiesel properties were analyzed and compared with ASTM standards. [ABSTRACT FROM AUTHOR]

Copyright of Revista Avances: Investigación en Ingeniería is the property of Universidad Libre, Facultad de Ingenieria and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)