Study of POSS-modified ZMS exchanging ammonia-nitrogen in water with Quantum Chemistry program based on DFT
In this work, the mesoporous zeolite molecular sieve (ZMS, SBA-15) was modified by polyhedral ologomeric silsesquioxane (POSS) with sodium carboxylates(-COONa) and sodium sulphonate (SO_3Na) as ion-exchanging active group. With this approach, the capacity of removing ammonia-nitrogen (NH_3-N) in water will be greatly increased because of changing and increasing of active groups. The exchangeing process between NH_3-N and the active group in the pore of POSS modified SBA-15 including sodium silanolate (-SiONa), -COONa and -SO_3Na was simulated by using Dmol~3 program of the Materials Stutio (MS)software which is the quantum chemistry program based on density functional theory (DFT). In the simulation process the transition state of the exchanging reaction was searched with LST/QST algorithm and the activation energy of reaction was calculated. As the results of simulation and calculation, the activation energy of exchanging reaction between NH3-N and sodium sulphonate (-SO_ 3Na) is smallest and the thermal effect of exchanging reaction between NH3-N and -SO_3Na is lowest in all exchanging reactions, which means the exchanging reaction between NH3-N and -SO_3Na proceeds more easily than others two exchanging reactions. The POSS_(SO3Na) is a better modifier for SBA-15 to remove NH_3-N in water.
Di Wang Peng Zhu Lijiang Hu
Material Science and Engineering College, Northeast Forestry University, Harbin 150040, China Chemis Chemistry Department, Harbin Institute of Technology, Harbin 150001, China
国际会议
哈尔滨
英文
800-804
2011-03-26（万方平台首次上网日期，不代表论文的发表时间）