Catalyst-loaded micro-encapsulated phase change material for thermal control of exothermic reaction

Abstract

CO2 methanation is a promising technology to enable the use of CO2 as a resource. Thermal control of CO2 methanation, which is a highly active exothermic reaction, is important to avoid thermal runaway and subsequent degradation of the catalyst. Using the heat storage capacity of a phase change material (PCM) for thermal control of the reaction is a novel passive approach. In this study a novel structure was developed, wherein catalysts were directly loaded onto a micro-encapsulated PCM (MEPCM). The MEPCM was prepared in three steps consisting of a boehmite treatment, precipitation treatment, and heat oxidation treatment, and an impregnation process was adopted to prepare a Ni catalyst. The catalyst-loaded MEPCM did not show any breakage or deformation of the capsule or a decrease in the heat storage capacity after the impregnation treatment. MEPCM demonstrated a higher potential as an alternative catalyst support in CO2 methanation than the commercially available α-Al2O3 particle. In addition, the heat storage capacity of the catalyst-loaded MEPCM suppressed the temperature rise of the catalyst bed at a high heat absorption rate (2.5 MW m−3). In conclusion, the catalyst-loaded MEPCM is a high-speed, high-precision thermal control device because of its high-density energy storage and resolution of a spatial gap between the catalyst and cooling devices. This novel concept has the potential to overcome the technical challenges faced by efficiency enhancement of industrial chemical reactions.

Sr-Doped Ca2AlMnO5 + δ for Energy-Saving Oxygen Separation Process

“…Approximately 0.13 g of the sample powder was placed as a packed bed in a quartz tube reactor (6 mm of ID, 554 mm of length) with quartz wool of 0.025 g put as the bed support. A similar configuration of the reactor set was reported elsewhere . Ar at 100 mL/min was initially introduced to keep the atmosphere in an oxygen-free condition.…”

“…A similar configuration of the reactor set was reported elsewhere. 28 Ar at 100 mL/min was initially introduced to keep the atmosphere in an oxygen-free condition. The reactor was then heated using an electrical furnace heater to a constant temperature at 550 °C.…”

Developing Composite Phase Change Material with Al–Si Base Microencapsulated Phase Change Material and Glass Frit for High Temperature Applications

“…Takahashi et al reported the use of a Ni catalyst on the surface of Al-25 mass% Si MEPCM and that the temperature increase due to heat generation during methanation reaction was suppressed by MEPCM. 27) This result shows the feasibility of microscale thermal control of catalytic reactions with the use of MEPCM. Another advantage of MEPCMs is that they can be molded into different shapes according to the type of heat exchanger.…”

Phase Change Thermal Storage Materials for Interdisciplinary Applications

“…(B) Thermal control performance of Ni/Al–Si@α-Al 2 O 3 microcapsule during CO 2 methanation. Reproduced with permission from ref . Copyright 2021, Springer Nature.…”