CO_2在三聚氰胺酚醛纤维上的吸附分离

CO_2 adsorption and separation on phloroglucinol-melamine-formaldehyde polymeric nanofibers

以三聚氰胺、间苯三酚和甲醛为原料,通过水热缩聚反应合成了三聚氰胺酚醛纤维(PMF),考察了温度对PMF合成的影响。以扫描电子显微镜(SEM)、透射电子显微镜(TEM)、N_2吸脱附和傅里叶变换红外(FT-IR)光谱等表征了PMF的形貌和结构,并采用体积法测定不同温度下CO_2和N_2在PMF上的单组分吸附平衡等温线。结果表明,在393 K下合成的PMF具有较大的比表面积(64 m2/g)和较高的CO_2吸附量(1.83 mmol/g,298 K、118 k Pa)。穿透柱实验表明,在298 K、200-600 k Pa,CO_2-N_2混合气在PMF上均可实现有效分离。将PMF在873 K下,N_2、H2及水蒸气等多种气氛中进行后处理,其比表面积和微孔孔容均显著增加,其中,在15%H_2O气氛中处理后,样品CO_2吸附量提高至2.83 mmol/g(298 K、118 k Pa)。

Phloroglucinol-melamine-formaldehyde polymeric nanofibers(PMF)were hydrothermally synthesized by a polycondensation method using melamine,phloroglucinol and formaldehyde as starting materials.The effect of temperature on the PMF synthesis was investigated.The morphology and structure of the as-synthesized PMF were characterized by the scanning electron microscope(SEM),transmission electron microscope(TEM),N2 adsorption-desorption and Fourier-transform infrared spectrometer(FT-IR)etc.Pure gas adsorption equilibrium isotherms of CO2 and N2 were determined by the volumetric method.The PMF sample synthesized at 393 K presented a higher specific surface area(64 m^2/g)and a higher adsorption capacity of CO2(1.83 mmol/g@118 kPa,298 K).Breakthrough column experiments indicated that efficient separation of CO2-N 2 mixtures could be achieved on the PMF at 298 K and various pressures ranging from 200 to 600 kPa.After the PMF was thermally treated at 873 K in various atmospheres such as N2,H2,water vapor,etc.,it was found that the specific surface area and micropore volume were greatly increased.Among the posttreated PMF samples,the one treated in 15%H2O stream showed an improved CO2 adsorption amount up to 2.83 mmol/g at 298 K and 118 kPa.