Butyric acid production from corn: economics of fermentative production of a novel biobased chemical.

In the present study, the economic evaluation of fermentation produced butyric acid (HBu) from corn was carried out (capacity 40 × 103 metric tons HBu∙yr-1) and two recovery processes (distillation and adsorption) were compared. Distillation is a longstanding process that has been effectively used to recover volatile chemicals. Recently, we developed an adsorption process that can be used to recover HBu cost competitively. The direct fixed capital (DFC) of the two processes (distillation & adsorption) were (in US dollars) $73.96 × 106 and $43.91 × 106, respectively. It is reported that the production of HBu from corn requires supplementing with amylase enzymes to the corn mash. For the two processes (distillation & adsorption) the annual operating costs were $37.67 × 106 and $31.83 × 106, respectively. The utilities annual costs for the two processes were $47.38 × 106 and $5.91 × 106, respectively. Corn price is one of the most important factors that influence HBu selling price, but other factors that could lower production costs include plant capacity. Factors such as tax on profit, interest rates on borrowed capital and plant life have marginal or low impact on HBu selling price. The significance of this paper is that HBu produced from corn and recovered by adsorption could be sold for $1.22 to 0.85∙kg-1. The selling price of fermentation produced HBu could further be reduced considerably if agricultural biomass such as wheat straw is used for production. One sentence summary Butyric acid production by fermentation and process economics.