原子能科学技术2026，Vol.60Issue(z1)：1-9,9.DOI:10.7538/yzk.2026.youxian.0159
液相硅烷化改性ZSM-5分子筛对NOx与水蒸气竞争吸附性能的影响
Effect of Liquid-phase Silane Modification on Competitive Adsorption Behavior of NOx and Water Vapor on ZSM-5 Zeolite
摘要
Abstract
To address the critical issue of rapid degradation in the denitrification performance of molecular sieves caused by competitive adsorption of water vapor in the high-humidity,high-concentration NOx exhaust gas generated during the reprocessing of spent nuclear fuel,in this study ZSM-5 zeolite was selected as the substrate and modified to be hydrophobic using a liquid-phase grafting method.Initially,six typical zeolites(ZSM-5,ZSM-22,MOR,SSZ-13,MCM-22,and β)were evaluated under 90％relative humidity.Despite SSZ-13 and β showing higher equilibrium capacities,ZSM-5 exhibits the steepest breakthrough curve,indicating the shortest mass transfer zone and lowest diffusion resistance.Furthermore,ZSM-5 demonstrates excellent cyclic stability with nearly 100％capacity retention after six adsorption-desorption cycles,and the lowest NOx desorption peak temperature(270℃),making it the optimal substrate for subsequent hydrophobic modification.Subsequently,the ZSM-5 was modified using five different silanes:TMCS,OTS,HMDS,PTMS,and BTS.Among these,butyltrichlorosilane(BTS)modification achieves the best balance between hydrophobicity and NOx adsorption capacity.Through dual-component NOx/water vapor breakthrough experiments and temperature-programmed desorption(TPD)tests,the adsorption separation performance,micro-mechanisms,and influence of carbon chain length on adsorption properties were systematically investigated.The results indicate that after BTS modification,the static water vapor adsorption capacity of ZSM-5 at atmospheric pressure decreases from 7.28 mmol/g to 5.22 mmol/g,a reduction of 28.3％.During high-humidity NOx adsorption breakthrough,the roll-up peak concentration ratio significantly decreases from 2.84 to 1.08,and the amount of NOx displaced by water vapor drops from 6.0 μmol/g to 0.5 μmol/g,demonstrating a substantial improvement in hydrophobicity.However,due to the steric hindrance introduced by surface-grafted silane groups,partial pore blockage occurs,and the catalytic oxidation of NO to NO2 is inhibited.Consequently,the NOx adsorption capacity of the modified sample slightly decreases from 39 μmol/g to 34 μmol/g,and the desorption product shifts from NO2 to NO.Despite this reduction in capacity,the modified material significantly lowers the NOx desorption temperature,with the peak temperature decreasing from 270℃to 85℃.Furthermore,within the carbon chain length range of C1 to C4,the hydrophobic gain brought by longer carbon chains gradually outweighs the steric hindrance loss,thereby improving the overall adsorption performance.This study provides new insights and a solid theoretical foundation for the development of low-temperature regenerative hydrophobic adsorbents suitable for the advanced purification of high-humidity NOx exhaust gases from nuclear facilities,offering a promising strategy to balance water resistance and adsorption capacity.关键词
ZSM-5分子筛/硅烷化/疏水改性/NOx吸附/竞争吸附/丁基三氯硅烷Key words
ZSM-5 zeolite/silanization/hydrophobic modification/NOx adsorption/competitive ad-sorption/butyltrichlorosilane分类
能源科技引用本文复制引用
汤云鹏,郭咏雪,李磊,陶海洋,王绎成,李子宜,刘佳鑫..液相硅烷化改性ZSM-5分子筛对NOx与水蒸气竞争吸附性能的影响[J].原子能科学技术,2026,60(z1):1-9,9.基金项目
国家自然科学基金(52370107) （52370107）
北京市科技新星计划(20240484685) （20240484685）
中核集团"青年英才"项目 （）
中核集团星原计划(CN-PE-8208) （CN-PE-8208）
