An Iterative Approach To Evaluate and Guide Fine Chemical Processes: An Example from Chloroaluminum Phthalocyanine for Photovoltaic Applications

This work demonstrates the use of a sustainability methodology that combines process-based life cycle assessment (LCA) and green chemistry metrics to evaluate and guide fine chemical synthesis. Using green chemistry principles and an iterative approach, alternatives are developed and evaluated using the proposed methodology until an alternative that simultaneously reduces the environmental impact, cost, and chemical hazard is found. The approach is demonstrated for chloroaluminum phthalocyanine (ClAlPc), which is a common donor material in organic photovoltaic. This study (1) demonstrates a new method to evaluate fine chemical manufacturing containing uncharacterized chemicals that combine LCA and green chemistry metrics, (2) provides life cycle inventories associated with various methods for ClAlPc synthesis, and (3) reports an optimized process for high-purity ClAlPc which simultaneously reduces the relative environmental impact by 3%, the cost by 9%, and the chemical hazard by 23% compared to the baseline process.