乙二胺-N-丙基改性硅胶的可控键合制备及其在银杏酸脱除中的应用研究

Controllable bonding preparation of ethylenediamine-N-propyl modified silica gel and its application in ginkgolic acid removal

优化了乙二胺-N-丙基键合硅胶(PSA)键合量可控的制备工艺,考察了PSA制备的批次重复性,并进行PSA制备的中试放大实验。采用红外光谱、元素分析及电位滴定法对所制备的PSA进行性能评价,结果表明:在3460 cm^(-1)处出现了N—H伸缩振动峰,在2960 cm^(-1)和2860 cm^(-1)处出现了—CH的不对称和对称伸缩振动峰,708 cm^(-1)处出现了—NH2的变形振动吸收峰,表明乙二胺-N-丙基成功接枝到硅胶表面;随着制备体系中硅烷化试剂比例的增加,碳、氮和氢元素的含量以及电位滴定法得到的离子交换容量均呈现上升趋势,说明乙二胺-N-丙基官能团的键合量逐渐增加。将制备的PSA填充成分离纯化小柱,考察了不同键合量PSA对银杏叶提取物中银杏酸的脱除效率,结果表明:PSA对银杏酸有强吸附能力,可应用于银杏叶提取物中银杏酸的脱除,2^(#)、3^(#)、4^(#)和5^(#)PSA分离纯化柱的最大上样体积分别为21、22、23、24 mL,且脱除效率随乙二胺-N-丙基键合量的增加而升高。

In this paper,the preparation process of N-propylethylenediamine bonded silica gel(PSA)with controllable bonding amount was optimized;the batch repeatability of PSA preparation was examined;and the pilot scale-up experiment of PSA preparation was conducted.The properties of the PSA were investigated by infrared spectroscopy,elemental analysis,and potentiometric titration.The results showed that N—H stretching vibration peaks appeared at 3460 cm^(-1),asymmetric and symmetric stretching vibration peaks of—CH appeared at 2960 cm^(-1)and 2860 cm^(-1),and deformation vibration absorption peaks of—NH 2 appeared at 708 cm^(-1),indicating that N-propylethylenediamine was successfully grafted onto the surface of silica gel.Furthermore,with the increasing proportion of silane reagent in the preparation system,the content of carbon,nitrogen,and hydrogen elements and the ion exchange capacity obtained by potentiometric titration showed an upward trend,indicating that the bonding amount of ethylenediamine-N-propyl functional group gradually increased.Moreover,the prepared PSA packing component was separated from the purification column,and the removal efficiency of ginkgolic acid from the extract of ginkgo biloba leaves using PSA with different bonding amounts was investigated.The results showed that PSA had a strong adsorption capacity for ginkgolic acid and could be used to remove ginkgolic acid from the extract of ginkgo biloba leaves,the maximum sample loading volumes for PSA separation and purification columns 2^(#),3^(#),4^(#),and 5^(#)are 21,22,23,24 mL,respectively.In addition,the removal efficiency was found to increase with the increasing amount of ethylenediamine-N-propyl bonding.