多氨基硅烷改性SBA-15分子筛对Cr^(3+)的吸附性能研究  

Preparation of Muti-Amino Silane Functionalized SBA-15 Molecular Sieve for the Adsorption of Cr^(3+) from Aqueous Solution

作　　者：陈强强[1] 齐迹 郭宇[1] 吴红梅[1] CHEN Qiang-qiang;QI Ji;GUO Yu;WU Hong-mei(School of Chemical and Environmental Engineering,Liaoning University of Technology,Jinzhou 121001,China)

机构地区：[1]辽宁工业大学化学与环境工程学院,辽宁锦州121001

出　　处：《化学试剂》2022年第12期1796-1803,共8页Chemical Reagents

基　　金：国家自然科学基金资助项目(21601075);辽宁省“兴辽英才计划”资助项目(XLYC2007171);辽宁省“百千万人才工程”资助项目(辽人社函〔2020〕78号);辽宁省自然科学基金资助项目(2021-MS-321)。

摘　　要：以多氨基硅烷(NQ-62)为改性剂,采用后嫁接法制备了氨基改性的SBA-15介孔分子筛(SN-SBA-15)。利用扫描电子显微镜、透射电子显微电镜、能量色散X射线光谱、X-射线衍射、氮气吸附-脱附、热重、红外光谱等表征手段对样品的形貌、结构进行了分析。结果表明,与SBA-15相比较,SN-SBA-15的比表面积和孔径较小,但表面形貌和晶体结构没有明显改变。以SN-SBA-15为吸附剂,对水中Cr^(3+)的吸附过程进行了动力学与热力学行为分析。研究表明,氨基改性过程可以显著增强SBA-15对Cr^(3+)的吸附能力,当溶液初始pH值为6.0,吸附时间为390 min,其最大吸附量可达88.6 mg/g。SN-SBA-15对Cr^(3+)的吸附过程符合准二级动力学模型,吸附行为可以用Langmuir模型描述,吸附为自发、吸热、熵增加的过程。而且,SN-SBA-15重复再生后吸附性能较稳定,经过5次吸附与再生循环,吸附量仅降低了16.1%。A novel amino-functionalized SBA-15(SN-SBA-15)was synthesized by using post-grafting method,in which 3-[2-(2-aminoethylamino)ethylamino]propyl-trimethoxysilane(NQ-62)was used as modified regent.The morphologies and structures of the samples were characterized by means of scanning electron microscope(SEM),transmission electron microscope(TEM),energy dispersive X-ray spectroscopy(EDX),X-ray diffraction(XRD),nitrogen adsorption-desorption,thermal analysis(TGA)and fourier transform infrared spectra(FT-IR).In comparison with SBA-15,SN-SBA-15 exhibited a smaller BET surface area and pore size,but the modification process did not make significant surface morphology and crystal structure of SBA-15 change.The SN-SBA-15 was used to remove Cr^(3+)from the aqueous solution.The adsorption kinetics and thermodynamics were investigated.The results showed that amino functionalization of SBA-15 improved the adsorption capacity toward Cr^(3+).When the pH value was 6.0 and the contact time was 390 min,the maximum adsorption capacity was up to 88.6 mg/g.The kinetic and adsorption isotherms of Cr^(3+)ions on the SN-SBA-15 were correlated well with the pseudo-second-order mode and Langmuir isotherm model.Thermodynamic analysis indicated that the adsorption process was a spontaneous endothermic process of increased entropy.Moreover,SN-SBA-15 exhibited good reusability for application in the adsorption of Cr^(3+)ions,the adsorption capacity of SN-SBA-15 showed a loss of 16.1%after 5 cycles of adsorption and regeneration.

关 键 词：SBA-15分子筛 氨基 改性 吸附 Cr^(3+) 

分 类 号：O655.4[理学—分析化学]