Moderne 40+ Acid Pretreatment Of Lignocellulosic Biomass. To treat lignocellulosic biomass, concentrated acids are also used. However, the following step of acid the experiments covered the recovery of sugars from carbohydrate of the lignocellulosic material, after their separation through a pretreatment process. Lignocellulosic biomass is one of the most abundant organic resources worldwide and is a promising source of renewable energy and bioproducts. Most commonly used acids are sulfuric acid or hydrochloric acid.