CIESC Journal ›› 2021, Vol. 72 ›› Issue (4): 2317-2327.DOI: 10.11949/0438-1157.20201182

• Material science and engineering, nanotechnology • Previous Articles     Next Articles

Fabrication of boron-doped hybrid silica membranes for pervaporation desalination

ZHANG Rui(),SHAO Qi,ZHANG Huayu,JIN Zelong,ZHANG Xiaoliang()   

  1. College of Chemistry and Chemical Engineering, Jiangxi Normal University, Nanchang 330022, Jiangxi, China
  • Received:2020-08-19 Revised:2020-09-18 Online:2021-04-05 Published:2021-04-05
  • Contact: ZHANG Xiaoliang

硼掺杂二氧化硅杂化膜的制备及渗透汽化脱盐性能

张锐(),邵琦,张华宇,金泽龙,张小亮()   

  1. 江西师范大学化学化工学院,江西 南昌 330022
  • 通讯作者: 张小亮
  • 作者简介:张锐(1996—),男,硕士研究生,rzhang2018@126.com
  • 基金资助:
    国家自然科学基金项目(21766011);江西省主要学科学术和技术带头人培养计划(20204BCJL22042)

Abstract:

Using 1, 2-bis(triethoxysilyl)ethane (BTESE) and boric acid as precursors, a boron-doped silica (B-BTESE- SiO2) hybrid membrane was successfully prepared by the sol-gel method. The boron element was confirmed to be successfully doped into silica frameworks during the sol-gel procedure by various characterizations of FTIR, XRD, XPS, TEM and SEM, which would form hydrothermally stable Si—O—B bonds. It could significantly influence membrane surface microstructure, hydrophilicity and pore size of B-BTESE-SiO2 hybrid membranes, and then improve their desalination performance and stability. The B-BTESE-SiO2 membranes prepared under the optimized condition of H3BO3/BTESE ratio as 0.25 in the sols, exhibited the strongest hydrophilicity, lowest mass transfer resistance (lowest activation energy during desalination process) and applicable pore size of 0.61 nm, thus demonstrating the highest desalination performance. The high water flux up to 16.5 kg·m-2·h-1 and NaCl rejection of nearly 100% were achieved for this SiO2 membrane towards 3.5%(mass) NaCl feed solution at 60℃. Moreover, this membrane showed excellent long-term stability (>168 h) and desalination performance for high-salinity [4.2%—15.0%(mass) NaCl] solutions, which had promising potential applications in seawater desalination and high-salinity wastewater treatment.

Key words: silica, membrane, desalination, hydrothermal stability, activation energy, high-salinity wastewater

摘要:

以1,2-双(三乙氧基硅基)乙烷(BTESE)和硼酸为前体,通过溶胶-凝胶法制备了硼掺杂的二氧化硅(B-BTESE-SiO2)杂化膜。采用FTIR、XRD、XPS、TEM、SEM等系列表征手段对合成溶胶及膜的结构和形貌进行了分析,结果表明:硼元素成功掺杂进入SiO2骨架中,形成了水热稳定的B—O—Si键,能明显影响膜表面的微观结构、亲疏水性、膜孔径大小从而提高膜的脱盐性能和稳定性。当溶胶中的H3BO3/BTESE比为0.25时所优化制备SiO2膜的亲水性最强,脱盐过程中活化能最低,传质阻力最小,膜孔径约为0.61 nm,故表现出最佳的脱盐性能。在60℃以3.5%(质量) NaCl溶液为进料液时,该膜的水通量高达16.5 kg·m-2·h-1,盐截留率近乎100%,并且表现出优异的长时间稳定性(>168 h)和高浓度盐水溶液[4.2%~15.0%(质量) NaCl]脱盐性能,在海水淡化和高盐废水处理等领域具有潜在的应用前景。

关键词: 二氧化硅, 膜, 脱盐, 水热稳定性, 活化能, 高盐废水

CLC Number: