Reorganization of Beaming in Ecological Perspective

The principal aim of the leather industry, which plays a significant role in today’s global economy, is to transform animal hides/skins into a physically and chemically stable material by subjecting them to chemical and mechanical processes. Leather processings involved in isolation in beamhouse processes generate large volumes of solid wastes and high loaded wastewater which are major source of environmental pollution characterized by chemical oxygen demand (COD), biological oxygen demand (BOD), total dissolved solids (TDS), total suspended solids (TSS), chromium (III) and phenolics with high pH, strong odor and dark brown color. In our study, the best practices modelling and eco-compatible process shifts were the objectives for the decrement in high pollution load of large effluent portion for leather industry. Soaking, immunization and liming processes were carried out with reductive chemical additives and surfactants, fibre opening auxiliaries, enzyme based and enzyme assisted chemicals in the factories as an eco-friendly designed recipe. The results revealed the advantages of time saving, cost effectivity, minimized pollution load and quality enhancement in limed pelts compared to conventional process

REMOVAL OF AROMATIC AMINES DERIVED FROM AZO DYES IN LINING LEATHERS BY OXIDATIVE BLEACHES

###EgeUn###Environmental aspects and ecological production has become a great challenge for leather industry. In this study, the possibility to regain of leathers consisting highly rate of harmful azo colorants were investigated. Sodium perborate, sodium percarbonate and hydrogen peroxide as oxidative bleaches were used for the removal of azo dyes in leather. Leathers were firstly bleached at the pilot scale. Color measurements of the leathers were carried out with spectrophotometric method following the bleaching processes. As a result of the calculation of color differences (Delta E), 7% sodium perborate were elicited as optimum parameter on the bleaching effect. After determining the optimal bleach at the pilot scale, bleaching and re-dyeing processes were performed on the batch production. With the bleaching process, 35 ppm of azo dye content in leather according to ISO 17234-1 standard method was reduced under 5 ppm. Chromium(VI) formation on bleached leather samples have been examined with UV-Visible spectrophotometer at 540 nm according to EN ISO 17075 standard. Textural changes on the leathers after bleaching process were also observed by strength tests and scanning electron microscope (SEM) analysis. According to the findings of the research, Cr(VI) contents were detected under 3 ppm and strength properties of leathers showed slightly decreases not in the statistically remarkable levels. By this practically applicable way in the industrial scale, resellability of the leathers was ensured and thus, the potential danger of banned arylamine compounds which are an important problem in ecological production and eco-labeling of leather has been eliminated.T.R. Ministry of DevelopmentTurkiye Cumhuriyeti Kalkinma BakanligiThe authors would like to thank Ata Dilek Leather Company for the technical assistance and financial support they provided. The authors also acknowledge the project of "Industrial Doctorate Program of Textile and Leather -2007 DPT 001" supported by T.R. Ministry of Development

Preparation, Characterization and Application of Lubricating Protein Filler for Sustainable Leather Production

WOS: 000538827000001In this study, collagen hydrolyzate was obtained from bovine shaving wastes of leather production with the alkali hydrolysis reaction. Total amino acid, total carbon and total nitrogen amounts of liquid collagen hydrolyzate (CH) were determined. Fourier-transform infrared spectroscopy (FTIR) characterization of collagen hydrolyzate was performed. Obtained CH was emulsified with hydrogenated castor and amino functional silicone oils to prepare lubricating protein filler (LPF). Particle size and zeta potential of the LPF were analyzed. 10%, 15%, and 20% LPF was used in the retanning/fatliquoring process of chromium tanned bovine leathers. Performance characterizations of leathers treated with LPFs were carried out with tensile strength, tear strength, filling efficiency, light fastness, shrinkage, and denaturation temperature analyses. Moreover, bounded fat content in leather was also determined. Results showed the increased thermal stability, strength performance and good filling effect in leather by application of the prepared LPF. Consequently, LPF had a good potential as natural retanning/fatliquoring agent via achieving reuse of the solid leather wastes and providing satisfactory leather properties and cleaner production by one product itself

Evaluation of Natural Dyeing of Leather with Rubia tinctorum Extract

WOS: 000295909400011The aspect of producing leather and textile products without impacting on the ecological balance, affecting both human and environmental health, is an important focal point to be pursued. Therefore, to address some of these issues a study was conducted to evaluate the efficiency of dyeing leather with madder, which is a 100% natural dyestuff from the extract of Rubia tinctorum and ascertain its friendly attributes to the environment. Treatment designs in the study included pre and post mordanting methods which were applied to selected types of leather and subsequently subjected to three different mordants: potassium aluminium sulphate [KAI(SO(4))(2).12H(2)O], copper sulphate [CuSO(4).5H(2)O] and ferro sulphate [FeSO(4).7H(2)O]. This approach was done to potentially obtain different colors and improve color fastnesses. In this study, the investigation was based on two primary source of tanned material, chrome and vegetable tanned leathers. Color measurements of the dyed leathers were carried out using a Minolta CM-508d brand spectrophotometer. On the other hand, dyestuff exhaustions were determined using a Shimadzu UV-1601 PC UV-Visible spectrophotometer. On the finished leather products, parameters such as color fastness to rubbing was determined with, the TS EN ISO 11640, color fastness to perspiration with, the TS EN ISO 11641, and color fastness to light with, the ISO 105-B02 standard method. Moreover these parameters were comparatively analyzed and reported. The results eventually indicated that the obtained color and color fastness values varied according to; the type of tanning method, mordanting method, and mordant type. Most of the result values obtained were generally at satisfactory levels which were between 3/4 and 5 fastness values. Different extraction methods, different mordants, and mordanting methods to be carried out in future are suggested so as to optimize the results of the current study.Ege University Scientific Research Project Department DirectorateEge University [2008-MUH-009]The authors would like to thank Ege University Scientific Research Project Department Directorate for the financial support they provided (Project No: 2008-MUH-009)

Reduction of Hexavalent Chromium Formation in Leather with Various Natural Products (Coridothymus capitatus, Olea europaea, Corylus avellana, and Juglans regia)

WOS: 000311128800013In this research, the extracts obtained from various natural products (hazelnut shells, thyme, olive shoots, and walnut leaves), which are indicated to have antioxidative characteristics, which are used during the retanning stage of leather manufacturing and their effects on chromium(VI) formation in leather was examined. Finished leathers were exposed to ageing conditions for 24h at 80 degrees C and for 24h and 72h at 80 degrees C under UV in order to enable chromium(VI) formation in the leathers. Chromium (VI) amounts in each leather sample were measured with a Shimadzu UV-1601 PC UV-Visible spectrophotometer at 540 nm according to the ISO/FDIS 17075 standard method, and how each extract affected chromium (VI) formation in leather was examined. According to the findings of the research; Coridothymus capitatus, Olea europaea, Corylus avellana, and Juglans regia extracts, which were used during the retanning stage of leather manufacturing, significantly reduced chromium(VI) formation in the leather under all three ageing conditions. The best reduction was obtained with Coridothymus capitatus extract in the ratio of 89.24% under the ageing condition of 24h/80 degrees C. It is recommended that different extraction methods, different natural extracts, and different ageing conditions be carried out in the future are to optimize the results of the current study

Comparison of different tanning agents on the stabilization of collagen via differential scanning calorimetry

WOS: 000403470800059Leather is composed of a three-dimensional weave of collagen fiber bundles. Collagen is a fibrous protein well organized in the formation of skin as building blocks. Leather production involves serial operations where the tanning plays the major role in improving the durability of leather products by stabilizing the triple helical structure of collagen matrix. In the leather-making industry, different tanning agents are used to produce different kind of leather goods. These tanning agents have varied efficiency on the stabilization of collagen. In this study, thermal stability of the leathers tanned with most commonly used tanning agents was evaluated by conventional shrinking test (CST) and differential scanning calorimetry (DSC) methods. The results showed that the thermal stability of leathers varied by the type of tanning agent which were in accordance with theoretical approaches. A distinct correlation was also observed between CST and DSC results of the tanned leathers

INVESTIGATION ON THE EFFECTS OF VARIOUS WASTE EXTRACTS ON FREE FORMALDEHYDE IN LEATHER

WOS: 000303360400016Due to the some chemical substances used in leather manufacturing, free formaldehyde is released in finished leathers and made serious problems for tanners. This situation causes the firms not to get Eco-Leather label and great problems are experienced about leather sales especially in recent years because natural and ecological products are in fashion. This study aims to reduce the free formaldehyde amount in leather by using various plant extracts (hazelnut shells, thyme, olive shoots, lavandula, ivy, christ's thorn seed), which are obtained from agricultural wastes, during rearming stage of leather processing. The analyses have been conducted with HPLC device according to IUC 19 (ISO TS 17226) method. According to the results; the extracts from hazelnut shells, thyme and olive shoots reduced the free formaldehyde amount on the leather by 35.49%, 33.86%, and 24.03% respectively. Color measurements on all finished leathers have been conducted with Konica Minolta CM-3600d brand spectrophotometer, light fastness analyses with ATLAS-XENOTEST ALPHA+ test instrument and according to ISO 105-B02 standard's method. The results showed that the plant extracts impacting formaldehyde considerably also improved the light fastness of the leather samples for a certain extent.Ege University Scientific Research Project Department DirectorateEge University [09-MUH-019]The authors would like to thank Ege University Scientific Research Project Department Directorate for the financial support they provided (Project Number: 09-MUH-019)