磷酰基乙酸改性粉煤灰基SBA-15及选择性吸附稀土性能

以粉煤灰为硅源合成了介孔二氧化硅SBA-15，对其进行磷酰基乙酸（PAA）功能化改性制备了PAA-SBA-15吸附剂，对改性前后的吸附剂进行了XRD，N2-吸脱附、红外光谱表征。结果显示，改性后SBA-15的孔道保持高度有序。将PAA-SBA-15用于模拟溶液中稀土离子吸附，发现PAA-SBA-15对Eu3+、Gd3+、Tb3+、Nd3+和Sm3+的吸附容量分别可达18.6、23.2、21.9、22.6和20.2 mg/g。考察了竞争离子Ca2+、Mg2+、Al3+和Fe3+对稀土离子吸附的影响。结果显示，Fe3+的存在对PAA-SBA-15吸附稀土离子干扰性最强。吸附动力学和热力学结果显示，PAA-SBA-15对稀土离子的吸附符合准二级动力学和Langmuir等温吸附模型，吸附过程中化学吸附占主导作用。     

杂多酸改性SBA-15对柴油氧化-吸附脱硫

用磷钨酸和磷钼酸改性SBA-15制备吸附剂,对直馏柴油、催化柴油进行氧化-吸附脱硫研究。结果表明,吸附剂对氧化后的油品吸附脱硫作用好于未被氧化的油品;经杂多酸改性后的SBA-15比单纯用SBA-15吸附脱硫效果更好;杂多酸负载量为30%时的吸附脱硫性能最好;SBA-15通过磷钼酸改性,其脱硫效果好于磷钨酸改性的SBA-15,直馏柴油的饱和吸附量可以达到17.32 mg/g;吸附剂对直馏柴油的吸附效果优于催化柴油。     

杂多酸改性SBA-15对柴油氧化-吸附脱硫

用磷钨酸和磷钼酸改性SBA-15制备吸附剂,对直馏柴油、催化柴油进行氧化-吸附脱硫研究。结果表明,吸附剂对氧化后的油品吸附脱硫作用好于未被氧化的油品;经杂多酸改性后的SBA-15比单纯用SBA-15吸附脱硫效果更好;杂多酸负载量为30%时的吸附脱硫性能最好;SBA-15通过磷钼酸改性,其脱硫效果好于磷钨酸改性的SBA-15,直馏柴油的饱和吸附量可以达到17.32 mg/g;吸附剂对直馏柴油的吸附效果优于催化柴油。     

Cu-β/SBA-15的吸附脱硫性能及吸附动力学

采用浸渍法制备Cu-β/SBA-15复合分子筛,通过XRD、N2吸附-脱附、NH3-TPD、Py-FTIR等对其进行结构表征,结果表明:Cu-β/SBA-15具有微-介孔复合结构和表面弱酸性。以Cu-β/SBA-15为吸附剂,在间歇式微型反应釜中,进行静态吸附脱除二苯并噻吩(DBT)实验,考察了反应温度、反应时间和剂油质量比("剂"指吸附剂Cu-β/SBA-15,"油"指模拟柴油)对吸附量的影响,并对其吸附动力学进行了考察。结果表明,在反应温度120℃,反应时间120 min,m(剂)∶m(油)=1∶30的条件下,模拟柴油的脱硫率可达54.62%、吸附剂吸附硫容量为2.27 mg/g;在Cu-β/SBA-15对DBT吸附的初始阶段,准二级动力学方程和Elovich方程均能很好地反映吸附模式,而整个吸附过程中,准二级动力学相关系数R20.99,拟合计算出的平衡吸附硫容量qe=2.54 mg/g,与实际所测值相差很少,说明准二级动力学吸附模型能更全面的描述Cu-β/SBA-15对DBT的吸附过程,其吸附过程是液膜扩散和内扩散共同作用的结果。     

磷酰基乙酸改性粉煤灰基SBA-15的制备及选择性吸附稀土性能

以粉煤灰为硅源合成了介孔二氧化硅SBA-15,对其进行磷酰基乙酸(PAA)功能化改性制备了PAA-SBA-15吸附剂,对改性前后的吸附剂进行了XRD、N2吸附-脱附、红外光谱表征.结果显示,改性后吸附剂的孔道保持高度有序.将PAA-SBA-15用于模拟溶液中稀土离子的吸附,发现PAA-SBA-15吸附剂对Eu3+、Gd3+、Tb3+、Nd3+、Sm3+的吸附量分别可达18.6、23.2、21.9、22.6、20.2 mg/g.考察了竞争离子Ca2+、Mg2+、Al3+、Fe3+对吸附稀土离子性能的影响.结果显示,Fe3+的存在对PAA-SBA-15吸附稀土离子干扰性最强.吸附动力学和热力学结果显示,PAA-SBA-15对稀土离子的吸附符合准二级动力学和Langmuir等温吸附模型,吸附过程中化学吸附占主导作用.     

有序介孔分子筛SBA-15的改性研究进展

综述了有序介孔分子筛SBA-15材料由于其骨架缺陷少,导致催化活性较低,为了扩展其在催化、大分子吸附领域的应用,需要在SBA-15表面引入活性组分的现状。从改性机理和方法出发,并结合了近年来国内外研究现状,SBA-15在金属改性和酸改性领域的应用,对今后的研究方向做出了展望。     

有序介孔分子筛SBA-15的改性研究进展

综述了有序介孔分子筛SBA-15材料由于其骨架缺陷少,导致催化活性较低,为了扩展其在催化、大分子吸附领域的应用,需要在SBA-15表面引入活性组分的现状。从改性机理和方法出发,并结合了近年来国内外研究现状,SBA-15在金属改性和酸改性领域的应用,对今后的研究方向做出了展望。     

磁性SBA-15/MIL-100(Fe)复合材料的制备及其吸附应用

采用水热法合成了3种含不同比例铁离子的磁性SBA-15/MIL-100(Fe)复合材料,利用XRD、紫外可见漫反射、傅立叶红外谱图等手段对样品进行了表征,结果表明成功制备了复合材料。用复合材料对刚果红溶液进行吸附,计算了吸附率及吸附量。实验结果表明,3种样品对刚果红溶液都有一定的吸附效果,吸附效果最佳的是含铁离子5%的磁性SBA-15/MIL-100(Fe),其最大吸附率为91.8%,最大吸附量为59.93mg·g^-1。探究了刚果红溶液浓度、体积、样品用量等因素与吸附率的关系,结果表明,溶液浓度越低,溶液体积越小,加入吸附剂的量越大,吸附率越高。     

短孔道介孔二氧化硅SBA-15对铀的吸附性能

以短孔道介孔二氧化硅SBA-15为铀吸附剂,考察吸附时间、初始液pH、初始浓度对吸附性能的影响,并分析了吸附动力学和吸附等温线以及吸附前后红外光谱变化。结果表明,初始液pH对吸附具有重要的影响,最佳吸附的pH值为6; 吸附在30 min即可达到平衡; 当初始浓度为100 mg·L^-1时,饱和吸附量为311 mg·g^-1;吸附量随铀溶液初始浓度的增大而增大,而吸附百分数则相反;吸附等温线符合Langmuir和Freundlich吸附模型,吸附动力学符合准二级动力学方程;吸附过程中起主要作用的基团是Si-OH和Si-O-Si。     

介孔SBA-15的孔径尺寸对小牛血清蛋白和溶菌酶蛋白吸附的影响(英文)

In this paper,the effects of pore-size of SBA-15 on the adsorption kinetics and equilibrium of large protein molecules Bovine serum albumin(BSA)and lysozyme(LYS)have been investigated.The mesoporous molecular sieve SBA-15 with six different pore sizes were synthesized with P123 triblock copolymer as the template agent,and 1,3,5-trimethylbenzene(TMB)and isopropyl alcohol as the pore-expanding agent.The samples were characterized by N2 adsorption/desorption,Scanning Electron Microscopy(SEM),Transmission Electron Microscopy(TEM)and X-Ray Diffraction(XRD).It is found that BSA and LYS were adsorbed rapidly on SBA-15 materials with large pores.The BSA adsorption capacity of sieve with the pore diameter of 21.4 nm reached 500 mg·g-1 within 25 minutes.However,if the pore diameter was smaller than 14 nm,the BSA adsorption capacity of the sieve was only about 220 mg·g-1.The adsorption equilibrium data fits in the Langmuir model,where the coefficient of effective use of specific area of mesoporous molecular sieve was found to be 0.03,0.18,0.37 and 0.48,corresponding to the pore diameter of 10.1 nm,13.2 nm,15.4 nm and 21.4 nm,respectively.The equilibrium loading amount of LYS on SBA-15 materials with pore size of 15.4 nm could be up to 1000 mg·g-1.The coefficient of effective use of surface area of mesoporous molecular sieve with diameter of 3.9 nm,7.4 nm,10.1 nm,13.2 nm and 15.4 nm was 0.10,0.47,0.56,0.71 and 0.79,respectively.It is also noted that greater pore size of mesoporous molecular sieve would lead to a higher coefficient of effective use of surface area.     

The selective adsorption of rare earth elements by modified coal fly ash based SBA-15

Rare earth elements (REE) are strategic resources and the recycling of REE in alternative resources is urgent and gets increasingly attention. However, the separation of REE in these alternative resources is still a challenge due to the low concentration of REE and multi coexisted ions in acidic system. In this study, the species distribution of REE within the pH 0-8.0 was calculated. The SBA-15 originated from coal fly ash was modified by two steps with (3-aminopropyl) triethoxysilane (APTES) and diethylenetriaminepentaacetic dianhydride (DTPADA) to obtain DTPADA-SBA-15 adsorbent, which was applied to the selective adsorption of REE. The results showed that DTPADA-SBA-15 possessed excellent adsorption performance on the selective adsorption of REE, including Eu, Gd, Tb, Nd and Sm, in acidic solution (pH 2) with multi competing ions. The FT-IR and Zeta potential characterization verified that the chemical adsorption through the coordination of O in DTPADA-SBA-15 with REE was dominant at lower pH value. The study of adsorption kinetics indicated that the adsorption of rare earth metal ions followed pseudo-second-order kinetic, of which the adsorption process followed the Langmuir isotherm model.     

SBA-15的改性及催化文冠果油制备生物柴油

以介孔分子筛SBA-15为载体,采用直接合成法和后合成法镀饰Al后再负载碱金属盐KNO₃,制得负载型固体碱催化剂KNO₃-AlSBA-15和KNO₃-Al-SBA-15。用XRD、BET、SEM以及CO₂-TPD对催化剂进行表征。结果表明：在SBA-15上镀饰Al可以保护分子筛的介孔结构;进一步负载KNO₃,能够增强催化剂的碱性。将其应用于催化文冠果油酯交换制备生物柴油,结果显示催化剂KNO₃-Al-SBA-15的催化活性最好,优于传统均相催化剂,所得生物柴油产率可达92%,重复使用多次仍具有较好的催化效果。     

Co-Mo／SBA-15柴油加氢脱硫研究

以介孔分子筛SBA-15为载体,担载Co—Mo双金属活性组分制备了深度加氢脱硫催化剂。通过XRD和BET表征表明,负载金属后SBA-15分子筛仍然保持二维晶相结构,表面积略有下降。以直馏柴油为原料,在固定床反应器上评价了催化剂的脱硫反应活性的结果表明,SBA-15介孔分子筛Co—Mo的负载量为W（CoO）=5％,w（MoO3）=25％;脱硫适宜的反应条件为：反应温度360℃,压力4．0MPa,氢油体积比400．0,空速2．0h^-1。在此条件下,柴油硫含量可由1350μg／g降至39μg／g。     

A comparative investigation on the properties of Cr-SBA-15 and CrOx/SBA-15

High-surface area and well-ordered mesoporous Cr-incorporated SBA-15 (Cr-SBA-15) and SBA-15-supported chromia (CrO_x/SBA-15) with Cr surface density = 0.05–1.11 Cr-atom/nm² have been prepared, respectively, using the one-step synthesis and incipient wetness impregnation method, and characterized by AAS, XRD, BET, ESEM, TEM, XPS, laser Raman, UV-Vis, FT-IR, and H₂-TPR. It is observed that the Cr-SBA-15 and CrO_x/SBA-15 samples showed an evolution of surface morphology from long chain-shaped to short rod-like and further to an irregularly spherical architecture at elevated Cr content, which might arise from the interaction of Cr ions or CrO_x domains with SBA-15. There were co-presence of tetrahedrally coordinated mono- and poly-chromate (Cr⁶⁺) as well as octahedrally coordinated Cr³⁺ species in Cr-SBA-15 and CrO_x/SBA-15, with the Cr⁶⁺ species being dominant at Cr surface density ≤0.22 Cr-atom/nm² in Cr-SBA-15 and Cr ≤0.54 Cr-atom/nm² in CrO_x/SBA-15, whereas the amount of the Cr³⁺ species increased markedly at Cr surface density ≥0.53 Cr-atom/nm² due to the formation of crystal Cr₂O₃ phase. Maximal Cr incorporation into Cr-SBA-15 and one monolayer surface CrO_x coverage on CrO_x/SBA-15 occurred at Cr surface density ≤0.53 Cr-atom/nm² and <1.11 Cr-atom/nm², respectively. The CrO_x/SBA-15 samples exhibited better reducibility than the Cr-SBA-15 samples, with the best reducibility exhibited at Cr surface densities of 0.54 and 0.12 Cr-atom/nm², respectively.     

SBA-15改性固体酸催化合成乙酸正丁酯的研究

以SBA-15为载体利用尿素水解法制备Zro2/SO2(4)-改性的固体酸SZ/SBA-15,通过XRD、N2吸附-脱附、IR、SEM 、Hammett指示剂法和N H3-TPD法对合成材料的孔结构、骨架结构及表面酸性等进行了表征.实验结果表明,所合成的固体酸催化剂具有典型的介孔结构特征,酸强度在0.80 < Ho <...     

P/SBA-15催化合成十六烷基苯

采用负载磷酸的SBA-15分子筛作为催化剂,以苯和十六碳烯为原料,经烷基化反应合成十六烷基苯。在微型液相固定床反应器上考察了反应温度、空速、体系压力、磷酸负载量以及苯烯摩尔比等反应条件对催化剂性能的影响。研究结果表明,磷酸的适宜负载量约为7%(质量分数),适宜反应条件为反应温度180℃、空速为2.0 h-1、体系压力为2.0 MPa和苯、烯摩尔比为10。在此条件下,十六碳烯的转化率可达到94.5%,十六烷基苯选择性可达93%。催化剂单程寿命达到120 h以上。负载磷酸的SBA-15催化剂呈现较好的催化活性和稳定性。     

介孔分子筛SBA-15在催化领域的应用进展

从负载固体酸催化剂、金属和金属氧化物以及手性催化剂三方面综述了介孔分子筛SBA-15在催化领域应用的研究进展;并展望了介孔分子筛SBA-15在催化领域的研究方向。     

Silver nanoparticles synthesized from mesoporous Ag/SBA-15 composites

Silver nanoparticles were prepared by removing silica from mesoporous Ag/SBA-15 composites. The results of nitrogen adsorption–desorption isotherms, X-ray diffraction, transmission electron microscopy and UV–vis spectroscopy indicated that Ag nanoparticles existed in the pore channels of SBA-15. Ag nanoparticles with diameters in the range of 2.5–5.5 nm and a narrow size distribution were confirmed by atomic force microscope images and energy-dispersive X-ray spectroscopy. UV–vis spectroscopy showed a broad emission peak of Ag nanoparticles centered at ca. 438 nm.