Font Size: a A A

The Study On CO2 Adsorption Performance Of Amino-functionalized Mesoporous Silica SBA-15

Posted on:2016-01-01Degree:MasterType:Thesis
Country:ChinaCandidate:H SunFull Text:PDF
GTID:2311330479952814Subject:Thermal Engineering
Abstract/Summary:PDF Full Text Request
Nowadays, the CO2 emission from the combustion of fossil fuels is the primary reason of the global climate change.In this case the technology of CO2 capture and separation has been put forward. Compared with the traditional method for CO2 capture, solid adsorption though rises later, it owns many advantages, so it gets a worldwide attention and a fast development.So it is important to develop a noval and effective adsorbent for CO2 capture and separation from flue gas.This paper study on the adsorption of several adsorbents, then choose SBA-15 as the supporter, through a wet impregnation technique to obtain the PEI functionalized mesoporous SBA-15. The static adsorption and dynamic adsorption performance of modified SBA-15 has been studied on different PEI load ratios.First, use a volumetric technique to research the CO2 static adsorption performance of four adsorbents(13X?Silica?MCM-41 and SBA-15). The influence of structure property, temperature, pressure on the adsorption capacity were analyzed, meanwhile the performance of the different adsorbents through eight regenerative cycles has been investigated. The pressure range is 0~100kpa,the temperature range is 293~308K respectively. The results shows that the adsorption of four adsorbents is physical adsorption and the order of the CO2 adsorption capacity is 13X>Silica>MCM-41>SBA-15. Compared with the heat of adsorption,the adsorption coefficient b plays a decisive role in adsorption. Though 13 X owns a higher adsorption capacity at a lower temperature, the high temperature of flue gas against the adsorption and the small pore size of 13 X is not suitable for modification.Then, choose SBA-15 which owns a bigger pore size and a bigger pore volume. The functionalized SBA-15 is prepared by impregnating mesoporous silica SBA-15 with polyethyleneimine(PEI) dissolved in ethanol. Using a volumetric technique to study the static adsorption performance of the modified SBA-15.The results shows that compared with unmodified SBA-15,the CO2 adsorption capacity of the modified SBA-15 has a obvious rise at a higher temperature. The CO2 adsorption capacity rises with the increase of the PEI load ratio. The adsorbents of load ratio 50%(SP-50) and 60%(SP-60)own a high CO2 adsorption capacity at 343 K and 363 K,the value is 0.930mmol/g(50% 343K)?0.900mmol/g(50% 363K)?0.955mmol/g(60% 343K)and 0.983mmol/g(60% 363K)respectively. Through eight regenerative cycles,the SP-50 and SP-60 sill have a high CO2 adsorption capacity.Finally, the dynamic adsorption of the modified SBA-15 has been studied. Firstly, the dynamic adsorption performance of SP-30?SP-40 and SP-50 at 343 K have been investigated. The results shows that the total adsorption capacity and breakthrough capacity rise with the increase of the load ratio of PEI,the adsorbent SP-50 owns the biggest adsorption capacity and breakthrough capacity, 0.920mmol/g and 0.637mmol/g respectively. Then the breakthrough curves of SP-50 at different temperatures(333K?343K and 353K)have been studied,the results shows that the SP-50 has a bigger adsorption capacity at 343 K compared with 333 K and 353 K.Furthmore,the adsorption capacity of SP-50 increased in hydrous environment. Finally,the SP-50 has a good adsorption performance through eight regenerative cycles.
Keywords/Search Tags:Carbon dioxide, Adsorbent, Adsorption capacity, Static adsorption, Adsorption isotherm, Dynamic adsorption, Breakthrough curve
PDF Full Text Request
Related items