it has been discovered that waste cross - linked polymer materials both synthetic and natural can be conveniently depolymerized at slightly elevated temperatures and moderate pressures by the action of a liquid chemical reagent . the proposed inexpensive process results in a substantial to total depolymerization of synthetic polymers and thereby recovers valuable liquid and solid materials . when applied to lignocellulosic biomass , the proposed process , depending on the reaction conditions , either unlocks the lignin - hemicellulose matrix making cellulose more available for fermenting microorganisms or results in carbonization , or coalification of the biomass that may be desirable in terms of sequestering excessive carbon from the earth &# 39 ; s biosphere .