Patent ID: 8378020

Claim:
A process for recovering a lignin derivative from a hardwood feedstock, the lignin derivative having an aliphatic hydroxyl content of 2.35 mmol/g or less, the process comprising: pulping the feedstock with a selected organic solvent (ETHANOL) supplemented with a selected acid catalyst (pH) for a selected period of time (TIME) at a selected temperature (TEMPERATURE) to produce a cellulosic solids fraction and an extractives liquid fraction; separating the cellulosic solids fraction from the extractives liquid fraction; and recovering the lignin derivative from an extractives liquid fraction, wherein the hardwood feedstock is an Acacia spp. and the parameters ETHANOL, pH, TIME, and TEMPERATURE are selected to satisfy the equation: 44.4758−17.3944*pH−0.342106*Temperature+0.373582*Ethanol−0.0133583*pH*Time+0.124198*pH*Temperature+0.000205204*Time*Time−0.00333743*Ethanol*Ethanol≦2.35.