(61a) Best Renewable Routes to Adipic Acid, Acrylic Acid and Propionic Acid

Many new synthesis routes from biomass resources to chemical building blocks are being researched; based on microbial, enzymatic, catalytic, or thermal conversions. For an industrial company it is hard to select the best route, as the information lacks a process concept design, and economic data. Generating the additional information for all process routes is very time consuming and costly.  

Therefore a process route selection method is derived requiring only some key information. As indicator for the feedstock cost the product yield on feedstock is used. For the investment cost the minimally required um number of process steps is taken. This is the sum of the minimum number of reactions and separation steps. The latter is derived from the stoichiometric equation. If not available, it can be derived from the chemical formulae of the products and feedstock. If solvents or additives are used then a separation step is added. The best process route has the highest yield of product on feedstock and the lowest number of process steps.  The selection method has been validated with four process routes researched in the past for the production of adipic acid from cyclohexane, benzene, phenol or butadiene of which the process route from cyclohexane is selected as the best. This is also the commercial winner.

With this method best renewable process routes have been selected for adipic acid, acrylic acid and propionic acid, all produced from glucose. These are presently produced at commercial scale from fossil resources. For each building block between 4 and 7 routes have been found in the public domain. The best process route for each building block has then been compared to the conventional commercial scale process from fossil resources on feedstock cost and investment cost. For the best biomass based process route a Technology Readiness Level assessment is made as well as an assessment of the Research and Development required to commercialisation. This includes an estimate of the effort to meet Safety, Health and Environment (SHE) criteria.