Biomass Depolymerization projects

Detoxification of Miscanthus Hydrolysates with a New Phase Separation Method - Completed

To facilitate biofuel production, removal of toxic compounds from lingocellulose hydrolysates is of great importance. Feng’s lab observed that an organic solvent (OS) that is miscible with water in all proportions can form a two-phase system with water when a low concentration of glucose, xylose, arabinose, fructose, maltose, sucrose or their mixtures was added into the OS-water solution. This new phenomena was named “sugaring-out.” In this project, Feng and his group explored the use of the sugaring-out system to remove inhibitory compounds from Miscanthus hydrolysates. Feng found that at high sugar concentrations the separation of the inhibitors, including furfural, was significantly higher than at lower concentrations.

project Highlights

2011 Highlights

Feng’s group tested a range of non-ionic co-polymers (Triton X 114, L64, L62LF, L61, and L62) to see whether they enhanced acetone-butanol (AB) production, and to extract and separate butanol from the fermentation broth.  They achieved a considerable enrichment of butanol production  (6 times) in the surfactant- rich phase over the control after cofermentation. In addition they showed that tri-block co-polymer L62 not only significantly enhanced butanol production, but also functioned as a good extractant for the separation of butanol from the fermentation broth.

2010 Highlights

In 2010, co-polymer surfactant L62 was used in butanol fermentation and increased the butanol yield by more than 200%.  After fermentation, the broth was separated into a surfactant-rich phase and an aqueous phase. An enrichment of butanol concentration (6 times) in the surfactant-rich phase over the control was achieved while the downstream process volume was reduced by 4-6 times. Butanol was separated from the surfactant-rich phase by evaporation, reaching a concentration of 106.8 g/L in the condensate. This process can be used to increase butanol yield and reduce production costs.

2009 Highlights

Feng examined the technical feasibility of this new approach by 1) examining the biocompatibility of selected surfactants; 2) examining the effect of temperature, surfactant concentration, and fermentation components and conditions on two phase formation and short chain alcohol partitioning; and 3) separating/recovering short chain alcohols from the surfactant-rich phase.



Published in 2012

Extractive Fermentation with Non-Ionic Surfactants to Enhance Butanol Production, Pradip Dhamole, Zhilong Wang, Yuanqin Liu, Bin Wang, Hao Feng, Biomass and Bioenergy,, February 25, 2012.

Published in 2010

Sugaring Out: A New Method for Removal of Acetonitrile from Preparative RP-HPLC Eluent for Protein Purification, Pradip Dhamole, Prafulla Mahajan, Hao Feng, Process Biochemistry, 45(10), pp. 1672-1676, October 2010.


Double Cloud Point of Ethylene Oxide-Propylene Osice Triblock CoPolymer in an Aqueous Solution, Zhilong Wang and Hao Feng, Colloids and Surfaces A: Physiochemical and Engineering Aspects, 362(1-3): pp. 110-116, June 5, 2010.


Phase Separation Conditions for Sugaring-Out in Acetonitrile-Water Systems, Pradip Dhamole, Prafulla Mahajan, Hao Feng, Journal of Chemical & Engineering Data, 55(9), pp. 3803-3806, May 19, 2010.



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