Process intensification for hydrogen production through glycerol steam reforming

Glycerol is the main by-product of biodiesel production and its use to produce hydrogen is a wise option not only because glycerol valorization would decrease biodiesel price, thus making it more competitive with other fuels, but also because glycerol is renewable. For this reason, in the last years, glycerol steam reforming (GSR) for green hydrogen production has been triggering the interest of the scientific community as a good alternative to other hydrogen production techniques. Recently, several researchers have been focusing their studies and efforts in GSR thermodynamics, developing new catalysts, studying and clarifying reaction kinetics and mechanisms, developing phenomenological reactor models as well as innovative reactor configurations. In this review, the last developments on catalysts and bi-functional materials, as well as the last advances on GSR in multifunctional reactors – namely membrane reactors (MRs) with H2 removal, sorption-enhanced reactors (SERs) with CO2 capture, and sorption-enhanced membrane reactors (SEMRs) that combine the in situ H2 and CO2 removal – are addressed while emphasizing the CO2-selective sorbents and H2-selective membranes with higher performances to be used in such devices. Scheme of a sustainable route for hydrogen production through glycerol steam reforming. [Display omitted] •Glycerol, a by-product from biodiesel manufacture, requires urgent utilization.•Glycerol steam reforming is an effective method to produce renewable hydrogen.•New catalysts for GSR should be active, stable and minimize coke formation.•Bi-functional materials are promising for improving the performance of GSR.•Innovative reactor configurations increase the hydrogen production during GSR.