# Experimental Study on Renewable Porous Carbon Dioxide Adsorbent Materials for Space Shuttles
###### Abstract
The results showed that the Avrami kinetic model was better than the quasi-first-order and quasi-second-order kinetic models for CO\({}_{2}\) adsorption, indicating that the adsorption process of CO\({}_{2}\) by the prepared adsorbent included both physical adsorption and chemical adsorption. [PERSON] et al. [16] reported a breakthrough experiment of packed-bed CO\({}_{2}\) adsorption using amine impregnation and amine-grafted silica adsorption material in the presence of SO\({}_{2}\), NO and NO\({}_{2}\) impurities. The effects of temperature, feeding concentration and amine loading on the dynamic adsorption capacity of the adsorbent were investigated. [PERSON] [17] prepared a novel amine-modified hollow mesoporous silica (HMS)@Mg-Al layered dihydroxide (LDH) composite to evaluate its CO\({}_{2}\) adsorption capacity. The amine-modified adsorbent showed stable adsorption performance in four consecutive adsorption/desorption cycles. [PERSON] et al. [18] prepared a carbon dioxide-imprinted solid amine adsorbent (IPEIA-R) using polyethylene imide (PEI) as the skeleton and glutaraldehyde crosslinked carbon dioxide as the pre-adsorption of PEI. The adsorption results showed that NaBH4 had an imprinting effect on CO\({}_{2}\) and the reduction in the imine group gave the adsorbent higher CO\({}_{2}\) adsorption capacity. [PERSON] et al. [19] reviewed the latest progress of solid-loaded amines for carbon dioxide capture, with emphasis on amine-functionalized metal-organic framework (MOF) materials. Diamine-functionalized Mg-DOBPDC MOF has good CO\({}_{2}\) capture performance, a unique adsorption mechanism, and good thermodynamic characteristics. [PERSON] et al. [20] synthesized a solid diamine adsorbent and discussed the effects of temperature, the dosage of mixed amine, the mass ratio of DMAEE to PEHA, and the partial pressure of CO\({}_{2}\) on CO\({}_{2}\) adsorption performance. [PERSON] et al. [21] functionalized activated carbon with two different amines, chitosan and triethylene tetramine. The results showed that the adsorbent functionalized by amine could significantly improve the adsorption capacity of CO\({}_{2}\). [PERSON] et al. [22] functionalized the synthesized mesoporous hollow silica with amine solid adsorbents for CO\({}_{2}\) capture. The morphological, structural, and textural properties of the amine-functionalized mesoporous hollow silica were characterized. In order to alleviate the phenomenon of amine aggregation in solid amine sorbents and achieve efficient CO\({}_{2}\) capture, [PERSON] et al. [23] synthesized a new dual-functional adsorbent by grafting 3-aminopropyl triethoxysilane and impregnating tetraethylenepentamine with the original mesoporous silica molecular sieve as the carrier. The effects of organic amine loading, gas flow rate and adsorption temperature on the adsorption performance of CO\({}_{2}\) were studied. Later, [PERSON] et al. [24; 25; 26; 27] studied gas adsorption in metal-organic frameworks and found that they were promising as adsorbents which could be coated by the amine. As reviewed above, the amount and heat of CO\({}_{2}\) adsorption in solid amines are key parameters in space shuttles. In fact, the case of a high amount and a low heat of CO\({}_{2}\) adsorption in a solid amine is the best option for space shuttles. In addition, the vapour existing in space shuttles affects CO\({}_{2}\) capture. During the CO\({}_{2}\) capture process, the adsorption heat will release which increases the temperature in the adsorption bed to lower the CO\({}_{2}\) adsorption amount. The degree of heat accumulation is controlled by the specific thermal conductivity of the solid amine. Therefore, water sorption and thermodynamical parameter measurements are necessary for space shuttle applications.