(412a) Process and Adsorbent for Separating Ethanol and Associated Oxygenates from a Biofermentation System

The principles of process intensification if used on existing processes can lead to development and redesign of existing processes to become more sustainable. This presentation will discuss a process and an adsorbent for the separation of ethanol associated oxygenates from a dilute mixture of ethanol and associated oxygenates in water in the presence of organic compounds derived from a biofermentation process. After pretreatment, the separation is carried out in a simulated moving bed adsorption system employing a stationary phase adsorbent comprising fluorinated carbon or modified C18 silica gel selective for the adsorption of ethanol and associated oxygenates, such as 2,3-butanediol, with a mobile phase desorbent selected from the group consisting of methanol, ethanol, propanol, and methyl tertiary butyl ether.

An improvement to the above SMB process is also discussed in which increasing the number of raffinate streams alone or in combination with a hot regeneration zone within the SMB cycle can significantly reduce the capital and operating costs associated with the incorporation of the SMB process to produce ethanol and butanediol from biofermentation effluent. This process is an improvement over conventional distillation which is very energy intensive and not practical for dilute fermentation broths.

The process is useful for removing water from dilute aqueous mixtures of organic compounds comprising ethanol in dilute concentration in water and produced by fermentation, biomass extraction, biocatalytic, and enzymatic processes which are not economically recoverable by conventional distillation methods