The importance of sustainable routes for the production of chemicals has increased over past few decades. The success of a biorefinery is based on its competitiveness with traditional refineries in terms of economics and process sustainability. This work aims to evaluate the environmental performance of cradle-to-gate production of p-Xylene from ligno-cellulosic biomass by a novel process involving the hydrolysis of biomass using Molten Salt Hydrates (MSH process) developed by Catalysis Center for Energy Innovation (CCEI) at University of Delaware and to compare with other existing hydrolysis processes including Dilute Acid (DA) and Concentrated Acid (CA) processes. The work is performed on ecoinvent database using ReCiPe and TRACI methods by a life cycle analysis software, SimaPro. Noticeably, CA and MSH processes perform better in climate change, fossil depletion and ecotoxicity when compared to the DA process. The main contributions for the MSH process arise from the processing of high amount of steam and cultivation and processing of biomass. Sensitivity analysis indicates a significant variance in the MSH process for different kinds of biomass feedstock used and for various energy scenarios for the generation of steam. The uncertainties resulting from the assumptions and developing technologies are assessed by performing uncertainty analysis using Monte Carlo Analysis.