Development Of Continuous-Type Equipment For The Reduction Of CO2 Under Hydrothermal Conditions

Abstract

To gain a new carbon resource and to decrease the CO2 emission are important task for sustainable development. As a mean for those, we had proposed a process for the reduction of CO2 by hydrothermal method. In this process, CO2, aqueous solution, and reductant are to react under hydrothermal condition, to generate organic compounds. This report is focused on the application of this process to continuous‐type process. In experiments, newly developed continuous‐type equipment has been used. In experiments, carbon steel cutting chaff as a reductant and Ni powder catalyst are settled in the reactor. CO2 gas and solvent were injected continuously into the heated and pressurized reactor. Initial materials are to react under hydrothermal conditions at 200 °C and 2.0 MPa. During the experimental period, reaction gas and liquid are collected successively. The samples are analyzed with GC and TOC. In treatment without Ni powder, organic compound was detected in neither reaction gas nor solution, while the occurrence of CO was confirmed. On the other hand, in the experiment with Ni powder additionally, formic acid was generated. It has been confirmed that the reaction process proceeds even in the continuous‐type treatment including the catalytic effect of Ni.