Organosiliceous nanotubes with enhanced hydrophobicity and VOCs adsorption performance under dry and humid conditions

Abstract

Organosiliceous nanotubes (OSNs) have been successfully prepared by a reverse micelle, then coated with mixed silica sources of tetraethylorthosilicate (TEOS) and 1,2-bis(triethoxysilyl)ethane, (BTSE). The OSNs were analyzed with different apparatuses and used for volatile organic compounds (VOCs) removal. The static pentane, hexane, benzene, toluene, 92# gasoline and water adsorption behaviors on OSNs and marketable activated carbon (AC) and silica gel (SG) were explored. Experimental results showed that the OSN-35% sample (mass ratio BTSE to (BTSE + TEOS) of 35% in feeding process) was uniform nanotubes with the biggest aspect ratio and pore volume had the best static VOCs adsorption capacity (1.35 g g− 1, pentane, 1.63 g g− 1, hexane, 1.68 g g− 1, benzene, 1.83 g g− 1, toluene and 0.973 g g− 1, oil vapor, respectively) and 0.247 g g− 1, water (the smallest). The dynamic monocomponent n-hexane and toluene adsorption performance on OSN-35% was evaluated via breakthrough curves, and the experimental results showed that OSN-35% had longer breakthrough times (tbs) and higher adsorption capacities compared with commercial adsorbents, and OSN-35% is water resistant under wet condition. For binary component (n-hexane and toluene) adsorption, the OSN-35% preferred to adsorb toluene. The larger VOCs capacity of OSNs was co-influenced by the introduction of organic groups, aspect ratio and pore volume. The OSNs with enhanced hydrophobicity and VOCs adsorption behaviors and excellent stability are potential for VOCs adsorption application.