Synthesis of imprinted amino-functionalized mesoporous silica and their selective adsorption performance of Pb2+, Cu2+, and Zn2

• Published in: Journal of sol-gel science and technology 2019-06, Vol.90 (3), p.465-477
• Main Authors: Yang, Hong, Fan, Jiaxi, Tian, Huijuan, Wang, Xiaoyu, Fu, Weng, Alam, Easar
• Format: Article
• Language: English
• Subjects: Adsorption; Aminopropyltriethoxysilane; Ceramics; Chemistry and Materials Science; Composites; Copper; Ethanol; Glass; Heavy metals; Inorganic Chemistry; Ions; Lead; Materials Science; Metal ions; Nanotechnology; Natural Materials; Optical and Electronic Materials; Organic chemistry; Original Paper: Fundamentals of sol-gel and hybrid materials processing; Response surface methodology; Selective adsorption; Silica; Silicon dioxide; Surface analysis (chemical); Surface chemistry; Synthesis; Tetraethyl orthosilicate; Zinc
• ISSN: 0928-0707; 1573-4846
• DOI: 10.1007/s10971-019-04985-6

The synthesis of imprinted amino-functionalized mesoporous silica (IAFMS) are using lead, copper, and zinc ions as imprinting species, anhydrous ethanol as a solvent, PEG-2000 as a template agent, tetramethylammonium hydroxide (TMAOH) as an auxiliary template agent, and tetraethoxysilane (TEOS) as a source of silica. The amino group was provided via the most common agent (3-aminopropyl)triethoxysilane (APTES). Based on the uniform design and response surface analysis, the optimum molar ratios of synthetic species such as APTES:heavy metal ions:TMAOH:PEG-2000:TEOS:anhydrous ethanol were determined as 0.270:0.065:0.25:0.073:1:50. Subsequently, Pb-IAFMS, Cu-IAFMS, and Zn-IAFMS were prepared with the same ratios as the above. Then, isothermal adsorption and selective adsorption of Pb(II), Cu(II), and Zn(II) were carried out. The results showed that the adsorption of heavy metal ions was mainly a chemical adsorption, the adsorbent surface was not a completely uniform adsorption, and a higher temperature was beneficial to the adsorption of heavy metal ions. Compared with q m values in the Langmuir model, the adsorption capacities of target ions onto imprinted materials can be 32.6–71.2% higher than those on the non-imprinted material. Values of relatively selective coefficients of IAFMS ranged from 4.35 to 18.45, which reveals the remarkable affinities of imprinted samples to the corresponding ions. Highlights Combining ion-imprinting and modification of amino groups into one step can successfully prepare IAFMS for selective adsorption of metal ions. In the binary ion system, the selective coefficients of the imprinted materials to the target ions are 4 times more than it of the non-imprinted one, and the anti-jamming ability is strong. The imprinted mesoporous adsorbent have a great regeneration performance, the modified amine components have good chemical stability.