Separation technologies for the recovery and dehydration of alcohols from fermentation broths

Abstract

Multi-column distillation followed by molecular sieve adsorption is currently the standard method for producing fuel-grade ethanol from dilute fermentation broths in modern corn-to-ethanol facilities. As the liquid biofuels industry transitions to lignocellulosic feedstocks, expands the end-product portfolio to include other alcohols, and encounters more dilute alcohol concentrations, alternative separation technologies which are more energy effi cient than the conventional approach will be in demand. In this review, alcohol recovery technology options and alcohol dehydration technology options for the production of ethanol and 1-butanol are reviewed and compared, with an emphasis on the energy footprint of each approach. Select hybrid technologies are also described.

Influence of fermentation by-products on the purification of ethanol from water using pervaporation

“…Hence, a lot of research was carried out in finding energetically more attractive separation techniques, such as gas/steam stripping (Ezeji et al, 2004), liquidliquid extraction (Bothun et al, 2002), adsorption (Carton et al, 1998) and pervaporation (Bowen et al, 2007;Fadeev et al, 2003;Ikegami et al, 2003;Nomura et al, 2002). These separation technologies for producing fuel grade ethanol from fermentation broths have been extensively reviewed by Vane and compared to the classical distillation process (Vane, 2008). Among proposed technologies, pervaporation may have advantages due to the simplicity of operation, the absence of extra chemicals, low energy requirements and hence low operational cost.…”

Capillary supported ultrathin homogeneous silicalite-poly(dimethylsiloxane) nanocomposite membrane for bio-butanol recovery

“…Ge-ZSM-5 [28], PTMSP [11,12], surface modified poly(vinylidene difluoride) (PVDF) [29], PERVAP-1070 [9], PDMS [7,9,15], poly(urethane) (PUR) [7], PEBA [7] membranes have also been reported for pervaporation separation of butanol-water mixtures. According to the economic appraisal by Vane [3], when butanol-water separation factor is larger than 30, the energy required for pervaporation of butanol will be less than that of distillation. Our silicalite-PDMS nanocomposite membrane meets this target.…”

“…Distillation is a traditional yet very energy intensive recovery option for butanol. Therefore, alternative recovery technologies that can lower the recovery costs, thus improving the bio-butanol economics are highly demanded, such as liquid-liquid extraction, adsorption, gas stripping, steam stripping, and pervaporation [3]. From an energy requirement perspective, pervaporation is considered to be one of the most attractive options [4].…”

Investigação Do Uso De Elevadas Razões De Compressão Com Etanol Hidratado Através Da Análise De Liberação De Calor

“…Em geral, as indústrias alcançam cerca de 5% v/v de etanol no caldo. Para aumentar a pureza de etanol de 5% para 94% v/v, um total de 6MJ/kg-etanol é gasto, o que representa 20% do poder calorífico superior do etanol [10][11][12]. Assim, torna-se claro que embora o etanol seja uma alternativa para substituir os combustíveis fósseis em motores de combustão interna é necessário, ainda, considerar os custos de produção e quantidade total de energia gasta na sua obtenção.…”