Sulfonic acid functionalized mesoporous silica based solid acid catalysts with different morphology were designed and fabricated.The synthesized materials were characterized by various physicochemical and spectroscopi...Sulfonic acid functionalized mesoporous silica based solid acid catalysts with different morphology were designed and fabricated.The synthesized materials were characterized by various physicochemical and spectroscopic techniques like scanning electron microscopeenergy dispersive X-ray spectroscopy,Fourier transform infrared spectroscopy,Brunauer–Emmett–Teller surface area,thermogravimetric analysis and n-butylamine acidity.The shape of catalysts particles plays an important role in its activity.The sulfonic acid functionalized mesoporous silica catalysts of spherical shape and the cube shape were assessed for catalytic activity in biodiesel production.The catalytic biodiesel production reaction over the catalysts were studied by esterification of free fatty acid,oleic acid with methanol.The effect of various reaction parameters such as catalyst concentration,acid/alcohol molar ratio,catalyst amount,reaction temperature and reaction time on catalytic activity were investigated to optimize the conditions for maximum conversion.It was sulfonated cubic shape mesoporous silica which exhibited better activity as compared to the spherical shape silica catalysts.Additionally,the catalyst was regenerated and reused up to three cycles without any significant loss in activity.The present catalysts exhibit superior performance in biodiesel production and it can be used for the several biodiesel feedstock’s that are rich in free fatty acids.展开更多
以月桂酸为阴离子表面活性剂,3-胺丙基三乙氧基硅烷(APTES)为共结构导向剂,合成了高含量氨基功能化介孔氧化硅材料(AFMS)。以AFMS为吸附剂对溶液中酸性橙7(AO7)进行吸附,对影响AO7吸附效率的相关因素进行了详细研究,结果表明,溶液p H值...以月桂酸为阴离子表面活性剂,3-胺丙基三乙氧基硅烷(APTES)为共结构导向剂,合成了高含量氨基功能化介孔氧化硅材料(AFMS)。以AFMS为吸附剂对溶液中酸性橙7(AO7)进行吸附,对影响AO7吸附效率的相关因素进行了详细研究,结果表明,溶液p H值及温度影响较大。吸附动力学表明,本研究中合成的AFMS对AO7的吸附速率极快。Sips吸附模型对吸附等温线模拟效果最好,从中可知AO7在样品D(由3.0 m L正硅酸乙酯及1.4 m L APTES合成)上的最大吸附量为1.26 mmol·g-1,远远高于相关文献报道的值。此外,通过吸-脱附循环实验证明,样品D具有良好的稳定性。展开更多
Although mesoporous silica with magnetically hybridized two-dimensional channel structures has been well studied in recent years,it remains a challenge to fabricate the counterpart with macroporous three-dimensional c...Although mesoporous silica with magnetically hybridized two-dimensional channel structures has been well studied in recent years,it remains a challenge to fabricate the counterpart with macroporous three-dimensional cubic structures since the highly acidic preparation conditions lead to dissolution of magnetic particles.Herein,we successfully prepared magnetic KIT-6 nano-composite and its amino derivatives by bearing acid-resistant iron oxide.The prepared materials exhibited excellent properties for U(VI)ions removal from aqueous solutions under various conditions.The experimental data show that the U(VI)adsorption features fast adsorption kinetics,high adsorption capacity and ideal selectivity toward U(VI).The adsorption process is of spontaneous and endothermic nature and ionic strength independence,and the adsorbents can be easily regenerated by acid treatment.Compared to pristine KIT-6,the introduction of magnetism does not reduce the efficiency of the material to remove U(VI)while exerting its role as a recovery adsorbent.The findings of this work further demonstrate the potential broad application prospects of magnetic hybrid mesoporous silica in radionuclide chelation.展开更多
基金Varsha P.Brahmkhatri also acknowledges TARESERB.TAR/2018/000547.Nanomission project“SR/NM/NS-20/2014”CNMS,JAIN deemed to be University is acknowledged for SEM facility。
文摘Sulfonic acid functionalized mesoporous silica based solid acid catalysts with different morphology were designed and fabricated.The synthesized materials were characterized by various physicochemical and spectroscopic techniques like scanning electron microscopeenergy dispersive X-ray spectroscopy,Fourier transform infrared spectroscopy,Brunauer–Emmett–Teller surface area,thermogravimetric analysis and n-butylamine acidity.The shape of catalysts particles plays an important role in its activity.The sulfonic acid functionalized mesoporous silica catalysts of spherical shape and the cube shape were assessed for catalytic activity in biodiesel production.The catalytic biodiesel production reaction over the catalysts were studied by esterification of free fatty acid,oleic acid with methanol.The effect of various reaction parameters such as catalyst concentration,acid/alcohol molar ratio,catalyst amount,reaction temperature and reaction time on catalytic activity were investigated to optimize the conditions for maximum conversion.It was sulfonated cubic shape mesoporous silica which exhibited better activity as compared to the spherical shape silica catalysts.Additionally,the catalyst was regenerated and reused up to three cycles without any significant loss in activity.The present catalysts exhibit superior performance in biodiesel production and it can be used for the several biodiesel feedstock’s that are rich in free fatty acids.
文摘以月桂酸为阴离子表面活性剂,3-胺丙基三乙氧基硅烷(APTES)为共结构导向剂,合成了高含量氨基功能化介孔氧化硅材料(AFMS)。以AFMS为吸附剂对溶液中酸性橙7(AO7)进行吸附,对影响AO7吸附效率的相关因素进行了详细研究,结果表明,溶液p H值及温度影响较大。吸附动力学表明,本研究中合成的AFMS对AO7的吸附速率极快。Sips吸附模型对吸附等温线模拟效果最好,从中可知AO7在样品D(由3.0 m L正硅酸乙酯及1.4 m L APTES合成)上的最大吸附量为1.26 mmol·g-1,远远高于相关文献报道的值。此外,通过吸-脱附循环实验证明,样品D具有良好的稳定性。
基金supported by the National Natural Science Foundation of China(Grant Nos.22276193,U20B2019,and U2067212)the National Science Fund for Distinguished Young Scholars(Grant No.21925603).
文摘Although mesoporous silica with magnetically hybridized two-dimensional channel structures has been well studied in recent years,it remains a challenge to fabricate the counterpart with macroporous three-dimensional cubic structures since the highly acidic preparation conditions lead to dissolution of magnetic particles.Herein,we successfully prepared magnetic KIT-6 nano-composite and its amino derivatives by bearing acid-resistant iron oxide.The prepared materials exhibited excellent properties for U(VI)ions removal from aqueous solutions under various conditions.The experimental data show that the U(VI)adsorption features fast adsorption kinetics,high adsorption capacity and ideal selectivity toward U(VI).The adsorption process is of spontaneous and endothermic nature and ionic strength independence,and the adsorbents can be easily regenerated by acid treatment.Compared to pristine KIT-6,the introduction of magnetism does not reduce the efficiency of the material to remove U(VI)while exerting its role as a recovery adsorbent.The findings of this work further demonstrate the potential broad application prospects of magnetic hybrid mesoporous silica in radionuclide chelation.
基金supported by the National Natural Science Foundation of China(Grant No.21673259)the Natural Science Foundation of Jiangsu Province of China(No.BK20171241)~~
