New nanosized catalytic membrane reactors for hydrogenation with stored hydrogen: Prerequisites and the experimental basis for their creation

The prerequisites and prospects for creating a new generation of nanosized membrane reactors are considered. For the first time, hydrogenation reactions take place in ceramic membrane pores with hydrogen adsorbed beforehand in mono- and multilayered oriented carbon nanotubes with graphene walls (OCNTGs) formed on the internal pore surface. It is shown for Trumem microfiltration membranes with D _avg ∼130 nm that oxidation reactions of CO on a Cu_0.03Ti_0.97O_{2 ± δ} catalyst and the oxidative conversion of methane into synthesis gas and light hydrocarbons on La + Ce/MgO are considerably enhanced when they occur in membranes. Regularities of hydrogen adsorption, storage, and desorption in nanosized membrane reactors are investigated through OCNTG formation in Trumem ultrafiltration membrane pores with D _avg = 50 and 90 nm and their saturation with hydrogen at a pressure of 10–13 MPa. It is shown that the amount of adsorbed hydrogen reaches 14.0% of OCNTG mass. Using thermogravimetric analysis in combination with mass-spectrometric analysis, hydrogen adsorption in OCNTG is first determined and its desorption is found to proceed at atmospheric pressure at a temperature of ∼175°C. It is shown that adsorbed hydrogen affects the transport properties of the membranes, reducing their efficiency with respect to liquids by 4–26 times. This is indirect confirmation of its high activity, due apparently the dissociative mechanism of adsorption.