Fuel cell electric vehicles have recently experienced rising demand. The geographic coverage of hydrogen stations, however, is limited. This study proposes an on-site hydrogen production system that converts heavy naphtha to high-purity hydrogen for remote areas without convenient access to hydrogen. It includes a pressurized steam reformer (SR) to produce H-2-rich gas and a catalytic membrane reactor (MR) to promote H-2-producing reactions and permeate hydrogen. By utilizing the liquid-fuel infrastructure, this compact system can produce hydrogen effectively and make it more accessible. Our paper describes how we maximize the system's hydrogen output by investigating how the operating conditions affect each component. Various tests are performed to select the system's water-gas-shift catalyst (Fe-Cr) and determine the optimal temperatures of the SR (800 degrees C) and the MR (400 degrees C). The MR shows enhanced catalytic performance from hydrogen permeation or 1.63 times higher hydrogen output at 25 bar(g) than a reactor that contains only catalyst (no membrane). At this pressure, the MR has a maximum hydrogen output at different SR reformate compositions. The maximization is possible by incorporating Le Chatelier's principle and minimizing methanation. This work is important because it proposes a comprehensive method to maximize on-site hydrogen output and ensure the MR's stable operation.