Published December 2022
Propylene glycol (PG) is a commodity chemical that finds use in a variety of applications, such as the production of unsaturated polyester resins, antifreeze, food additives, cosmetics, and pharmaceuticals. PG has been commercially produced predominantly from crude-derived propylene and propylene oxide. With the growth of the biodiesel market buoyed by government subsidies, glycerin, a major by-product of biodiesel production, is an increasingly competitive and greener alternative as a feedstock for PG production.
This review presents the techno-economic analysis of the GT-ProGSM technology by Sulzer GTC Technology US, LLC (Sulzer GTC) for producing PG from glycerin via a simple one-step process. We discuss the industry status of PG, its properties, and its uses. Based on the information obtained from the public domain and inputs from Sulzer GTC, a design is presented for a plant to produce United States Pharmacopeia-grade PG industrially via glycerin hydrogenolysis. The production economics assessment in this review is for a plant based at a US Gulf Coast location, with a capacity of 110.2 million pounds per year [MMlb/yr] (50 kilotons per year [kt/yr]) of PG.
While the production economics assessment in this review is based on a US Gulf Coast location, an Excel®-based tool, iPEP Navigator® is also provided to allow a quick calculation of the process economics in other major regions of the world. The technological and economic assessment of the process is the Process Economics Program’s (PEP) independent interpretation of a potential commercial process, and it may not reflect in whole or in part an actual plant configuration. We do believe that the assessment is sufficient to represent the process as well as the process economics within the range of accuracy necessary for economic evaluations of a conceptual process design.