Catalyst and reactor have always been two key elements in chemical manufacture, because catalyst is viewed as the core of catalytic reaction by which to accelerate the reaction rate and control reaction direction, and meanwhile reactor is correlated to the mass transfer, fluid flow and pressure drop, etc. Until now, researchers still work hard on improving the performance and functionalization of these two important elements, so as to push forward the industrialization process of chemical industry as much as possible. It is worth noting that researches focusing on the functional integrations of catalysts and reactors are, however, rarely reported in decades of development, especially for those harsh reactions that need to be performed upon high temperature and high pressure.
Three-dimensional (3D) printing is a category of rapid prototyping technology by layer-to-layer way allowing the fabrication of complex structures with geometric shape, controlled composition, and function that are unattainable through conventional manufacturing techniques. In this study, we revolutionized catalyst and reactor by accomplishing the integration of the dual function using 3D printing technology, to create self-catalytic tubular reactors (Fe-SCR, Co-SCR and Ni-SCR). These 3D printing reactors were, for the first time, applied to realize direct conversion of C1 molecules (CO, CO2 and CH4) into high value-added chemicals Fischer-Tropsch (FT) synthesis, CO2 hydrogenation and CO2 reforming of methane (see Figure 1).
Figure 1: 3D printing self-catalytic reactors for FT synthesis, CO2 hydrogenation and CO2 reforming of methane.
Taking into consideration on the limitation that Co- and Fe-based supported catalysts are difficult to be reused for FT synthesis, the proposed 3D printing self-catalytic tubular reactors show an unprecedented innovation. The 3D printing tubular reactor can be highly reused by in situ regeneration, and the experimental results indicated that the tubular reactor presented extreme reliability for repeated runs in FT synthesis. Moreover, the tubular reactor with alloy property poses considerably strong hardness, which is able to withstand high reaction pressure such as 5 MPa in our tests. To unfold high flexibility and freedom in our tubular reactor designs, we conducted the geometrical studies on the Co-SCR for FT synthesis. Surprisingly, the inner geometric configurations of tubes exhibit obvious differences in product distributions (gasoline, jet fuel, and diesel), further declaring that these controllable 3D printing structures effectively tuned FT product distributions. These innovative characteristics show distinctive superiorities in contrast to those of conventional powder catalysts.
Conventional powder catalyst needs binder to form catalyst pellet in huge commercial plant. But the binder often decreases catalyst intrinsic ability. Our new 3D printed self-catalytic reactor erases the troublesome binder problem. More importantly, our new self-catalytic reactor, without extra catalyst loading into the reactor, can downsize the micro-reactor dramatically.
If you're interested in this research, you are appreciated to visit the website for further reading. The website for research article publication on “Nature Communications” is as follows: https://www.nature.com/articles/s41467-020-17941-8.
Laboratory of Prof. Noritatsu Tsubaki, http://www3.u-toyama.ac.jp/tsubaki/eng%202007/eng.htm