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High-performance chrome-free leather production is currently one of the most concerning needs to warrant the sustainable development of the leather industry due to the serious chrome pollution. Driven by these research challenges, this work explores using biobased polymeric dyes (BPDs) based on dialdehyde starch and reactive small-molecule dye (reactive red 180, RD-180) as novel dyeing agents for leather tanned using a chrome-free, biomass-derived aldehyde tanning agent (BAT). FTIR, 1H NMR, XPS, and UV-visible spectrometry analyses indicated that a Schiff base structure was generated between the aldehyde group of dialdehyde starch (DST) and the amino group of RD-180, resulting in the successful load of RD-180 on DST to produce BPD. The BPD could first penetrate the BAT-tanned leather efficiently and then be deposited on the leather matrix, thus exhibiting a high uptake ratio. Compared with the crust leathers prepared using a conventional anionic dye (CAD), dyeing, and RD-180 dyeing, the BPD-dyed crust leather not only had better coloring uniformity and fastness but it also showed a higher tensile strength, elongation at break, and fullness. These data suggest that BPD has the potential to be used as a novel sustainable polymeric dye for the high-performance dyeing of organically tanned chrome-free leather, which is paramount to ensuring and promoting the sustainable development of the leather industry. [ABSTRACT FROM AUTHOR]

Making out animal skins or hides to leather is commonly called as tanning. This research was done for utilizing tannins of some medicinal plants and tannin induced green-synthesized silver nanoparticles along with minimal concentration of chromium to enhance the physical and mechanical properties of leather and thereby reducing the pollution caused by chromium in effluent which crucially affect the soil fertility, ground and surface water. In this study, Cassia alata, Euphorbia hirta, Thespesia populnea and Wrightia tinctoria were collected and tannins were extracted from the leaves. Tannins were utilized for production of silver nanoparticles. The extracted tannins and tannin induced silver nanoparticles were characterized, where the silver nanoparticles were found to be crystalline. Further, the tannin and tannin induced silver nanoparticles were used in leather processing either alone or in combination with chromium. The quality of tannin/silver nanoparticle treated leather was compared with chemically tanned leather for its tensile strength, tear strength, shrinking temperature, etc. [ABSTRACT FROM AUTHOR]

The present discourse entitled Leather tanning in medieval cities of today's Slovenian Styria mostly concerns itself with the question of medieval-citizen-craftsmen trying to achieve a prestigious position within their city's hierarchy. The analysis was done using the already published literature as well as published and unpublished primary sources. Even though the emphasis is on cities of today's Slovenian Styria, the comparison was also made with the ones of contemporary Carniola and the Slovenian Littoral. We must admit that the leather tanning craft during the middle ages was relatively low as far as prestige goes. Even so we can surmise, that many tanners were able to reach for the highest positions of a certain city's administration. This was especially true for the artisans in smaller cities. [ABSTRACT FROM AUTHOR]

The objective of the work presented in this paper is the identification of innovations and new processes in split leather. For this, a process of technological surveillance was done through the search of information referred to canine toys, process technologies, normativity, and trends. Life cycle analysis of the technologies through S curves was applied. Among the most important documents found were two new processes for the manufacture of canine toys described in two patents in the United States. Also, for split leather flour its inflection point in articles was presented in the period 2016-2018, which represents an opportunity to continue research on this technology. [ABSTRACT FROM AUTHOR]

The objective of this research was to reduce the non-quality costs in a production system of leather tanning. The research was based on the case study of a Brazilian company that has been facing financial instability caused by quality problems of the production system. The results showed that the leather softness variable is responsible for 80% of the nonquality costs. The findings of the research also revealed internal difficulties in accepting the implementation of quantitative quality controls implemented by employees at the plant's operational level. Overall, the research discussed the importance for leather companies investigating the root causes of quality problems in order to reduce costs with rework and customer returns. Among the implications for companies in the leather manufacturing industry, was the need to improve the skills of employees with new quality management techniques to meet the growing competitiveness of the market. [ABSTRACT FROM AUTHOR]

Jurash in which was located on the border between Hijaz and Yemen was located on the point of world trade routes coming from China and Indiain the ancient time. That means doors of the city were open to the World in terms of economy, social and cultural communitions. Secondly, through red-haired camels, sheeps called al-Hadhf and grapes called al-Jurashan Jurash had a rightful reputation in the peninsula. In addition, producing catapulte is to indicate that the city had a significant development level regarding to culturel development. Furthermore, recently held archaeological finds have revealed that Jurash was one of the most important settlements on the caravan route extending along with the Red Sea to the North. While all of given information in the article would partly uncover to enlighten the relevant period for researchers studying on, it would also give contrubition to comprehension and interpretation of the Qur'an and sunnah at a certain rate. [ABSTRACT FROM AUTHOR]

Titanium-tannin (Ti-TA) complex is used in the modern leather technology as an alternative of chromium tannage and as an effective modification of vegetable tanning. The ratio between metal and tanning reagent is a key factor for minimizing the unused quantities of tannic acid that could reach the environment by waste waters and cause damages on aqueous ecosystems. However, a lack of reliable data about Ti-TA complexation limits the possibility for fine tuning of the composition of tanning solutions. This study is aimed at characterization of titanyl-tannin complex: its structure, stoichiometry and stability constant. The data of alpha-coefficient of titanyl-hydroxocomplexation at different pH values were also presented.The results obtained showed that in the concentration interval 5x10-6 − 2x10-5 M and pH 4, the main titanium IV species in titanyl/tannin/formate solutions is titanyl-hydroxo-tannin complex TiO(OH)TA. It was proved by UV-Vis and IR spectrometry that the aromatic carboxylic oxygen (Ar-C=O) and probably phenolic oxygen of tannin are involved in the coordination of titanyl ion. The stability constant of TiO(OH)TA was estimated: lgβ = 16.53. The obtained molar ratio curves and the calculated values of the equilibrium constants could be used in leather technology for selecting an appropriate composition of tanning solutions. [ABSTRACT FROM AUTHOR]

Abstract: Cork boiling wastewaters were processed by nanofiltration (NF) in order to concentrate phenolic compounds, whose tanning power allows their application in the leather tanning process as a retanning agent, and to produce a permeate suitable for reuse in the cork boiling operation, according to the International Code of Cork Stopper Manufacturing Practice. Four commercial polymeric membranes were selected and tested at laboratory scale: NTR7450, Desal-DK, NF90 and NF270. The feed volume reduction factor (VRF) was defined to be equal to seven or higher, and the operation was carried out in a batch mode at 15 bar and 25 C. The performance of the different membranes was evaluated determining membrane permeability and rejection coefficients for several pollutant indicators: total organic carbon (TOC), colour, absorbance at 254 nm and salt content. Two membranes were selected to perform pilot-scale studies, NF270 and NF90, based on their performance in this process. The results obtained in the laboratory and pilot-scale studies permitted the development of a mass balance model, which was calibrated with experimental data. Additionally, a technical and economical evaluation study was performed, which showed that the process proposed in this work is viable for industrial application. [Copyright &y& Elsevier]

Abstract: The potential of chestnut shell and eucalyptus bark extracts as phenol substitutes in the formulation of adhesives, as chrome substitutes in leather tanning and as a source of antioxidants compounds has been studied. The influence of extraction conditions, type and concentration of alkaline compounds (NaOH, Na2SO3 and Na2CO3) and temperature, on extraction yield and on extract characteristics: Stiasny number, tannin content, total phenols content, FRAP (ferric reducing/antioxidant power) antioxidant capacity and molecular weight distribution was analysed. Chestnut shell extracts had much better properties than eucalyptus bark extracts and significantly higher extraction yields were obtained. The increase of temperature from 70 to 90°C not only increased the extraction yield but also improved the quality of the extracts. For both materials, the 2.5% Na2SO3–90°C extract, together with the 2.5% NaOH–2.5% Na2SO3–90°C extract for chestnut shell, showed high extraction yields and the best properties for all the applications proposed. [Copyright &y& Elsevier]

This paper evaluates model-based upgrading of an activated sludge plant treating wastewaters of leather tanning industrial district with an average capacity of 13,000 m3/d. Significant impact of temperature changes on biochemical processes, such as nitrification and denitrification were quantified and used in setting the aeration control for process optimization in terms of total nitrogen removal. Model evaluation based upon kinetic and stoichiometric parameters specifically determined for the tannery wastewater, indicated that an intermittent aeration type of an operation strategy was suitable for achieving the required effluent total nitrogen level of 100 mgN/L under all operating conditions at the process temperature range of 21°–C35°C. The simulation study also showed that the nitrification performance of the plant was improved by increasing the aeration intensity. The application of intermittent aeration provided a competitive advantage in meeting the total nitrogen standards, improving the total nitrogen removal to around 60%. [ABSTRACT FROM AUTHOR]

Abstract: This study was designed to investigate the composition and the toxicity of leather tanning wastewater and conditioned sludge collected at the leather tanning wastewater treatment plant (CODISO) located in Solofra, Avellino (Southern Italy). Samples were analyzed for their conventional parameters (COD, TSS, chromium and ammonia) and for metal content. Effluent samples included raw wastewater, and samples collected following coagulation/flocculation process and biological treatment. A set of toxicity endpoints were tested using sea urchin and marine microalgal bioassays by evaluating acute embryotoxicity, developmental defects, changes in sperm fertilization success and transmissible damage from sperm to the offspring, and changes in algal growth rate. Dose-related toxicity to sea urchin embryogenesis and sperm fertilization success was exerted by effluent or sludge samples according to the following rank: conditioned sludge>coagulated effluent⩾raw influent>>effluent from biological treatment. Offspring quality was not affected by sperm exposure to any wastewater or to sludge samples. Algal growth was inhibited by raw or coagulated effluent to a similar extent and, again, the effluent from the biological treatment resulted in a decreased toxicity. The results suggest that coagulated effluent and conditioned sludge result in higher toxicity than raw influent in sea urchin embryos and sperm, whereas the biological wastewater treatment of coagulated effluent, in both sea urchins and algae, cause a substantial improvement of wastewater quality. Hence a final biological wastewater treatment should be operated to minimize any environmental damage from tannery wastewater. [Copyright &y& Elsevier]

Examines the case of a woman presented with a two-day history of vesicular dermatitis on the dorsum of both feet. Sensitivities to plasters, sanitary towels and condoms with spermicide; Use of gum rosins and tall oils in leather-tanning process; Use of colophonium as adhesive.