Assessing the energetic and environmental sustainability of organic borazines preparation: A comprehensive life cycle assessment and uncertainty analysis

Abstract

Since its inception, organic synthesis has played a fundamental role in the development of society, as its efficiency is essential for the preparation of materials in several strategic sectors such as pharmaceuticals, transportation and energy. In this context, organic borazines have emerged as promising molecules useful both as doping units and organic semiconductors, particularly in the production of photovoltaics and organic transistors. However, like most “fine chemical” products, their engineering is generally complex and harmful to the environment due to the need for dangerous reagents, solvents, and harsh reaction conditions. Recent adopted advancements in the manufacturing process, including continuous-flow synthesis and the use of safer, biomass-derived solvents, have been confirmed through a comprehensive cradle-to-gate life cycle assessment (LCA). The study, compared to four batch processes from the literature, identified electricity consumption as the primary contributor to environmental and human health impacts. Additionally, it was demonstrated that adopting a continuous-flow approach, which reduces electricity consumption and leverages safer reaction media such as 2-MeTHF, characterized by an exceptional recovery rate (90%), proved to be an effective strategy, resulting in a notable 11% reduction in emissions. Furthermore, an uncertainty analysis using the Monte Carlo method revealed that energy mixes reliant on fossil fuels increase the impacts across all categories related to human health damage.