Towards environmental protection and process safety in leather processing – A comprehensive analysis and review

Leather process industry requires in-plant process interventions with inherent safety; wherein, enhancement in process efficiency, rather than end-of-pipe treatment are gaining importance. Switching over to alternate processes with statutory requisite such as material safety and toxicological information of chemicals employed, eco-label, Registration, Evaluation, Authorization and Restriction of Chemicals (REACH) and UN’s Sustainable Development Goals (SDGs) for Leather sector (SDGs) are essential. Herein, these aspects have been linked with safer and eco-benign process development. The present review analyze the environmental, occupational safety concerns and difficulty in overcoming the conventional non eco-benign chemicals, in order to develop alternative cleaner processes through scientific basis with fundamental theory and practice of leather manufacture. Aspects such as mass balance, diffusion phenomena, E-Factor metrics for assessing the clean technology and pollution reduction have been explained. Focus given towards improving exhaustion levels in various stages, eco-benign processes, non-toxic products, use of natural materials, bio-process, novel processes/products, new process systems, 3 R approach, process intensification tools such as ultrasound are analyzed with environmental and cost aspect. In addition, concepts of process safety, modernization of tannery and process engineering of leather making to identify the need for benign methods in processing have been incorporated. Analysis of life cycle assessment and carbon footprint relevant to leather sector are also provided. This unique and novel review includes 257 references with recent information, leading to environmental protection and process safety. The distinctive approach and analysis presented here provides methodology and novel approach for development of eco-benign alternatives, chemicals and systems for Leather and other generic processing industries for green & sustainable development and also form a typical model for preparedness towards future challenges for sustainable development. This comprehensive analysis and review would pave way for switch over from conventional leather process, which has environmental and safety concerns to alternate eco-benign products, processes and systems.