Identifying barriers to scaled-up production and commercialization of chitin and chitosan using green technologies: A review and quantitative green chemistry assessment
Shegufta Shetranjiwalla, Arlene Ononiwu
Abstract
Chitosan (CHT) production from Chitin (CH) is a billion-dollar industry but is constrained by multi-step chemical extractions that are energy and wastewater-intensive. Numerous green recovery technologies (GRT)s have paved the path for sustainable extraction, however, these have not been adopted for scale-up or mainstream commercialization. Therefore, this review critically evaluates the chemical, biological, combined biological-chemical and GRTs for CH/CHT recovery on commercially important criteria such as yields, molecular properties, cost/gram, water & energy use and wastewater & GHG emissions to identify barriers that hinder (i) the scaled-up, cost-effective commodity production of CH/CHT using GRTs (ii) the preparation of CH/CHT standards and (iii) the successful pathway from CH/CHT recovery to commercialization of chitosan-based products, supporting United Nations Sustainable Development Goals (UN SDG)s, particularly SDG 12. To arrive at the data-driven assessment, techno-economic and green chemistry metrics such as PMI and E-factor were calculated. The industry-developed quantitative green chemistry evaluator DOZN™ was used to assess resource & energy efficiency and human & environmental health hazards for CHT production. Mechanochemistry was identified as a viable GRT based on the limited literature available for quantitative assessment, and increasing the yield from GRT processes was identified as key to improving economic performance while also reducing environmental impacts.