- ItemOpen AccessFrom Leather Wastes back to Leather Manufacturing: The Development of New Bio-Based Finishing Systems(MDPI, 2023-04-16) Gargano, Marika; Bacardit i Dalmases, Anna; Sannia, Giovanni; Lettera, VincenzoThe leather industry is currently between two opposing paths: on the one hand, recent legislative trends in terms of the eco-sustainability of industrial processes are leading leather manufacturing towards the development of cleaner production methods; on the other hand, the spread of new alternative materials to leather is driving the leather industry to improve its competitiveness by developing new innovative and high-quality products. Leather finishing is one of the most important phases of leather production, and is capable of improving its quality and organoleptic properties. However, this phase is characterized by the use of polluting chemical products, such as volatile organic compounds, potentially toxic crosslinking agents, and hardly biodegradable resins. In this context, this research work aims to develop a finishing formulation capable of giving leather the durability and quality properties required by the market, while at the same time, being eco-sustainable. Specifically, the aim of the present work is to suggest a new finishing formulation in terms not only of green technology but also of a circular production flow, by recovering solid leather wastes. The developed finishing system is based on the application of collagen, extracted from tanned wastes through an enzymatic treatment, to be cross-linked and bound to the leather surface. This new bio-based leather finish is compared to a resin-based leather finish, and shows the same quality standards as those requested by the market.
- ItemOpen AccessExploring the feasibility of substituting mimosa tannin for pine bark powder. A LCA perspective(Elsevier, 2022) Conde Mateos, Mireia; Combalia Cendra, Felip; Baquero Armans, Grau; Ollé i Otero, Lluís; Bacardit i Dalmases, AnnaThe use of vegetable tannins is a bio-based alternative to chrome tanning. The most used vegetable extracts are Mimosa and Quebracho. To improve the sustainability of the tanning process, a chemically unmodified pine bark could be used as a natural source of tannins. The present study was aimed to evaluate the environmental impact of the use of pine bark powder to obtain vegetable leather through a life cycle assessment. Specifically, the life cycle impact evaluation was performed for both: i) pine bark powder tannin and the atomized mimosa extract production as raw material; and ii) the production process of a tanned leather with pine bark tannin versus a tanned leather with mimosa extract. An eco-friendly and cleaner production method for obtaining pine bark powder was developed. This new production method allows to obtain a reduction in 83% in the 'climate change' impact category. However, when this tannin is applied to obtain a tanned leather, the tanning process shows an increase in all studied impact categories compared with the use of the atomized mimosa extract.
- ItemOpen AccessAnalysis of the environmental impacts of waterproofing versus conventional vegetable tanning process - A life cycle analysis study(Elsevier, 2021-10-11) Baquero Armans, Grau; Sorolla, Sílvia; Cuadros Domènech, Rosa; Ollé i Otero, Lluís; Bacardit i Dalmases, Anna; A3 Leather Innovation CenterWaterproofed vegetable leather is desired for its 'greenness' in front of chromium-tanned waterproofed leather. However, conferring waterproofing capabilities to vegetable tanned leather maintaining light color and a soft touch is a fact of great concern for leather goods producers. Sustainable and technical requirements are currently demanded by high-quality brands in order to pass the threshold established by Leather Working Group (LWG) initiatives to earn their environmental audit seal. The research work has focused on testing various mineral salts and hydrophobic products compatible with vegetable tanned leather. According to the obtained results, acrylic copolymers along with zirconium salts are necessary to achieve the desired leather properties. The present study provides the environmental comparison of a new vegetable tanning process to give waterproofing capabilities with the conventional vegetable tanning process. The comparison comprises both wastewater analysis and environmental impacts in a life cycle assessment (LCA) framework. The paper also outlines the comparison using different life cycle impact assessment (LCIA) methods. Further, the study provides specific data on leather vegetable tanning processes. Comparative analysis has been focused on the two diverging stages for both conventional and waterproofing vegetable tanning processes, namely retanning and fatliquoring. Conventional process environmental impacts are lower than waterproofing process impacts according to LCA methodology. However, wastewater analysis shows no major differences between both processes. Main contributors to these results are the zirconium salts, dispersing agents and acrylic copolymers used along with an increase in energy consumption due to processing times. Alternative methods used in the impact assessment lead to similar results, revealing no major differences in the comparative results between methods in this case.
- ItemOpen AccessStudy of the impact on occupational health of the use of polyaziridine in leather finishing compared with a new epoxy acrylic self-crosslinking polymer(Elsevier, 2021-02-16) Ollé i Otero, Lluís; Frías Álvarez, Aroha; Sorolla, Sílvia; Cuadros Domènech, Rosa; Bacardit i Dalmases, AnnaThe leather industry needs innovative products to meet the continued demands of the global market. To achieve a good performance in the finishing operation, crosslinking of the polymers used in this leather production stage is necessary. These crosslinkers are irritating and harmful. This study is based on the synthesis of functionalized acryl polymers with epoxy groups to improve the properties of the leather finishing to avoid the use of external crosslinkers, and consequently; harmful products for health and the environment will not be necessary. Likewise, the affectation in the health of workers exposed to crosslinker has been investigated when the leather finish is carried out. To do this research, a clinical analysis has been carried out prior authorization of the workers. The study demonstrates a good performance finishing avoiding the use of crosslinkers. In addition, it has been determined that molecular fragments of the decomposition of polyaziridine are present in the urine of one of the employees. Although the human metabolism may metabolize these polyaziridine fragments being non detectable in the urine samples, a positive result was obtained in the analysis by GC-MSD of the urine, and therefore; it could affect the health of this employee.
- ItemOpen AccessEvaluation of a new sustainable continuous system for processing bovine leather(Elsevier, 2015-08) Bacardit i Dalmases, Anna; Baquero Armans, Grau; Sorolla, Sílvia; Ollé i Otero, LluísThe aim of the present work is to evaluate a new sustainable continuous system for processing bovine leather. By means of a prototype described in the international patent WO, 2010/070571 (A2) of the technological centre AIICA, a dehydration process for bovine hides is carried out. What is obtained through this new process is a dehydrated leather with the optimal physical and chemical characteristics that will allow its subsequent tanning by immersion processes in aqueous solutions of chemical products. When compared to existing traditional processes, there are economic and environmental advantages resulting from the use of this new system. More specifically, the new process results in reductions of 30.6% in water use, 50.2% in chemical use and 16.4% in process time. In addition, a reduction of 27.3% in wastewater and a reduction of 47.5% of thermal energy consumption are obtained. However, this new system presents an increase in electricity consumption of 63.03% and an increase in gaseous emissions of 75% due to the use of acetone in the dehydration process and the 0.5% losses of acetone during the process. In order to better assess the environmental impact of this new tanning system, life cycle analysis methodology has been chosen to perform calculations on the Global Warming Potential (CO2 equivalent emissions) and the energy consumption comparing both traditional and new tanning processes.