Making Biofuels Part 1

Lecture Notes

This summarizes the barriers to efficient and cost effective conversion of lignocellulosic feedstocks into ethanol. First, recall that the cell wall recalcitrance and separating lignin from cellulose and hemicellulose is one barrier. The fact that we're dealing with a small-scale batch system is a second barrier to this process. As we examine the feedstocks, the cost of producing feedstocks and particularly the cost of transporting and storing the feedstocks is a barrier. Determining which pre-treatment, whether chemical, such as acid or alkaline materials, or thermal using heat is a barrier. In the hydrolysis and scarification steps, enzyme costs and enzyme activities are a concern. Again, we're dealing with a variety of feedstock and the enzyme tends to be specific. And then finally in the fermentation step, converting C5 sugars from the xylose in the hemicellulose into ethanol is difficult. Overcoming these barriers of converting lignocellulosic feedstocks into ethanol in an efficient, cost-effective manner will speed commercial adoption.