Measurement of reaction temperature distribution inside of methanol steam reforming microreactor using infrared thermography

Methanol steam reforming is a promising method for in-situ hydrogen production and greatly affected by the reaction temperature inside the microreactor, while the inside reaction temperature distribution is quite difficult to be measured. Here, we developed a visible methanol steam reforming microreactor using optical crystal as observation window and using infrared thermography to measure the real-time reaction temperatures. The method of using infrared thermography to measure the distribution of reaction temperature was presented and characterized with the accuracy of 98.4 % in the range of 300.0-575.0 K. Then, temperature heating and hydrogen production tests were conducted, and results showed that the lower oxygen to carbon (O/C) ratio leads to higher heating rate of 18.0 K/min during microreactor heating stage. The measured temperature distribution on the copper foam increases with a stable gradient of 0.91 K/mm along the reactant flow direction and the temperature difference in vertical direction is less than 10.0 K. The maximum methanol conversion is 98.0 % at the gas hourly space velocity (GHSV) of 3600 mL/(g center dot h) and maximum reformate flow rate is 100.8 mL/min at the GHSV of 6000 mL/(g center dot h). The obtained results demonstrated that the visible methanol steam reforming micro-reactor and reaction temperature measurement method would be beneficial for future microreactor's design.