We want to understand how well different types of forest biomass can be converted to biofuel. Knowing this, we can recommend the technologies that may be most efficient.

Research Question

The purpose of this project is to determine the suitability of forest biomass to be processed into intermediates for biofuels production. These chemical intermediates include fermentable sugars, synthesis gas, and pyrolysis bio-oils. We will process several different types of forest biomass using several advanced processing strategies and analyze the chemical products to see what sort of biofuel intermediates are produced from each combination of starting material and processing technology. Another important statistic will be the yield, or the amount of each chemical intermediate we can expect to obtain from a given amount of starting biomass. This knowledge will inform our recommendations about what types of biomass conversion technologies and reaction conditions could be most efficiently applied to specific forest feedstocks in Michigan. 

Approach

We collected representative samples of hardwoods and softwoods present in Michigan forests from other project researchers, as well as energy crops that could be planted on abandoned agricultural lands in forest regions (poplar, willow, switchgrass).  Laboratory-scale conversion processes in this research included many of the methods being currently used in the emerging biofuels industry, along with a few new technologies: dilute acid hydrolysis, steam expansion, ionic liquid extraction of lignin, fast pyrolysis, and gasification.  Products from these conversion processes were analyzed for speciation (identity of chemicals) and yield. Analyses conducted include high performance liquid chromatography (HPLC), gas chromatography / mass spectroscopy (GC/MS), and image analysis of native and residual biomass. 

Progress and Results

In previous research, we obtained conversion data on dilute acid hydrolysis of aspen, basswood, red maple, balsam, switchgrass (sample from the National Renewable Energy Laboratory- NREL), and two hybrid poplar clones obtained from Dr. Victor Busov of the School of Forest Resources and Environmental Sciences at Michigan Tech.  Optimum conditions of temperature, acid concentration and time in reaction were examined for these species.  We applied these same experimental methods to new forest feedstocks; poplar and willow. A final report summarizes experimental findings and identifies the most suitable processing routes for each candidate forest feedstock to achieve high efficiency conversions.

Final Project Report:

Evaluation of Forest Biomass Processability