Preparation And Adsorption-catalysis Performance Of Aminated Porous Material

Amino functionalized porous materials is far better than the unmodified porous materials in the adsorption, separation and catalyst, which improved its application value greatly, and will be applied in some new areas. Thus, the development of amino functionalized porous materials got a lot of attention. In this paper, amino functionalized SBA-15 and AC were prepared by the modification of SBA-15 and AC. Meanwhile, the modified porous materials have been characterized by fourier transform infrared spectroscopy, X-ray diffraction, thermo gravimetric analysis, nitrogen adsorption desorption and environmental scanning electron microscopy.The SBA-15 was prepared using tetraethyl orthosilicat as the raw material by hydrothermal method, and activated to increase the quantity of Si-OH by stirring SBA-15 in hydrochloric acid solution. Amine modified SBA-15 (NH2-SBA-15) was synthesized though amino-functionalization of the activated SBA-15 with 3-Aminopropyl triethoxysilane. The test results showed that NH2-SBA-15 possessed large surface area, stable skeleton structure, and high amino contents (14%). Moreover, the CO2 temperature programmed desorption experiments (CO2-TPD) of the as-prepared NH2-SBA-15 were conducted. Moreover, the CO2 temperature programmed desorption experiments of the as-prepared NH2-SBA-15 were studied, and the results show that the introduction of amino groups results in the increase of the basic sites of SBA-15, which is beneficial to the adsorption of CO2.The synthesis procedure of NH2-AC involves the following steps. First, the activated carbon was oxidized by acid according to the modified Hummers method, and the reaction product is called COOH-AC. Second, the COOH-AC was via acyl chlorination, which produced COC1-AC. Third, the COC1-AC was aminated, which produced NH2-AC. The results showed that the as prepared NH2-AC had a large surface area and stable skeleton structure, and the decomposition temperature is 4300℃.Pd/C catalysts were prepared using NH2-AC as carrier by impregnation reduction method, which produced NH2-AC-Pd. The X-ray diffraction of NH2-AC-Pd showed that the Pd particles could be uniformly dispersed on the surface of NH2-AC. The as-prepared NH2-AC-Pd catalyst was used in the reduction of nitrobenzene to aniline by NaBH4. Results show that the conversion of nitrobenzene over NH2-AC-Pd in an on stream time of 8 min was 99%, and the NH2-AC-Pd catalyst could be reused for five successive cycles with a conversion of>99%. Moreover, Pd(Ⅱ) adsorption behavior of NH2-AC was studied. Results show that the high catalytic performance and excellent recyclability of NH2-AC-Pd catalyst is attributed to the high adsorption capacity of NH2-AC, which is beneficial to improve the catalytic activity. The present study provided an approach for the development of noble metal catalysts to improve the adsorption amount of the carrier.