Enhancement in Enzymatic Hydrolysis by Mechanical Refining of Pretreated Biomass

International Congress on Energy (ICE)
AIChE Annual Meeting
November 1, 2012 - 4:15pm-4:45pm
Cellulose is the most abundant natural polymer.  Therefore, cellulosic bioethanol has been identified as a fuel source that has tremendous potential to supplement the United States consumption of non-renewable transportation fuel sources.  Although cellulosic bioethanol is poised for market entry, several processing problems and high processing costs have has been identified as barriers to commercialization.  In order to make cellulosic bioethanol economically viable, these barriers (including high enzyme and raw material costs, and the natural resistance of biological degradation of a plant; “biomass recalcitrance”) need to be overcome.  This study looks at the effectiveness of refining (a mechanical post-treatment) in addition to the traditional pretreatment step to assist in overcoming the biomass recalcitrance barrier.  Laboratory scale refining was conducted using a disk refiner, a PFI mill, and a valley beater at different refining severities to determine which refining mechanisms allowed for the most substantial gains in enzymatic hydrolysis conversion.  Studies were conducted using green liquor pretreated hardwood, and also various lignin content kraft (NaOH + Na2S) pretreated hardwood.  Initial results show that refining allows for significant improvements in enzymatic hydrolysis yield.  Enzymatic sugar recovery of alkaline pretreated hardwood increased from 55.9% to 81.9% with 5 FPU/g after mechanical refining.  Enzyme reduction of more than 50% was achieved at the same level of sugar recovery.  To investigate the reason for increased digestibility, pore volume and surface area were evaluated in a wet state using three independent analyses; Water retention value, Simons’ staining, and DSC thermoporometry methods. A strong correlation was found between sugar recovery and measured properties.
Professional Development Hours
0.5 PDHs
You will be able to download and print a certificate for these PDH credits once the content has been viewed. If you have already viewed this content, please click here to login.

Would you like to access this content?

No problem. You just have to complete the following steps.

You have completed 0 of 2 steps.

  1. Log in

    You must be logged in to view this content. Log in now.

  2. Purchase Technical Presentation

    You must purchase this technical presentation using one of the options below.
    If you already purchased this content recently, please click here to refresh the system's record of ownerships.


Credits 0.5 Use credits
List Price $25.00 Buy now
AIChE Members $15.00 Buy now
AIChE Undergraduate Student Members Free Free access
AIChE Graduate Student Members Free Free access