This work presents a process-system engineering study of an integrated catalytic conversion strategy to produce bio-based platform molecules (levulinic acid (LA), furfural (FF), and prOpyl guaiacol (PG)) from hemicellulose (C5), cellulose (C6), and lignin fractions of lignocellulosic biomass. A commercial-scale process based on the strategy produces high numerical carbon yields (overall yields: 35.2%; C-6-to-LA: 20.4%, C-5-to-FF: 69.2%, and Lignin-to-PG: 13.3%) from a dilute concentration of solute (1.3-30.0 wt.% solids), but a high recovery of these molecules requires an efficient separation system with low energy requirement. A heat exchanger network significantly reduced the total energy requirements of the process. An economic analysis showed that the minimum selling price of LA as the highest value-added product (42.3 x 10(3) t of LA/y using 700 x 103 dry t/y of corn stover) is US$1707/t despite using negative economic parameters, and that this system can be cost-competitive with current production approaches. (C) 2017 Elsevier Ltd. All rights reserved.