非定域密度函数计算微波改性天然沸石的介孔分布(英文)  

Nonlocalized density functional theory used to evaluate mesopore size distribution of Chinese natural zeolite modified by microwave irradiation

作　　者：柳旭升[1,2] 马军[1,2] 杨晶[3] 刘乾亮[1,2] 沈吉敏[1,2] 

机构地区：[1]哈尔滨工业大学市政环境工程学院,哈尔滨150090 [2]哈尔滨工业大学水资源与环境国家重点实验室,哈尔滨150090 [3]哈尔滨工业大学建筑设计研究院,哈尔滨150090

出　　处：《黑龙江大学自然科学学报》2014年第2期211-217,共7页Journal of Natural Science of Heilongjiang University

基　　金：Supported by the National Science&Technology Pillar Program of China(2012BAC05B02);the Open Project of State Key Laboratory of Urban Water Resource and Environment,Harbin Institute of Technology(QA201208);the Funds for Creative Research Groups of China(51121062)

摘　　要：采用微波加热离子交换方法改性天然沸石以增加其介孔容量，同时以传统回流加热离子交换方法制备的改性沸石作为对照，用非定域密度函数理论（NLDFT）和氮气在柱状、孔状硅介质上的吸附模型为依据，计算不同加热方法改性沸石的孔径分布曲线。结果表明，所选择模型和实际测得的样品等温线有很高的拟合程度。与传统BJH方法相比，NLDFT方法可以提供更多的孔径分布信息。相对于未改性沸石，微波加热改性天然沸石的介孔直径增加3～5nm，而常规回流加热只增加直径在3nm以下的介孔。这主要是由于沸石颗粒在回流加热过程中相互剧烈摩擦，导致沸石的结构受到破坏，沸石由层片状变为粉末状，而微波加热改性后的天然沸石仍保持原来的层片状。微波加热法提供了一个高效的天然沸石介孔容量增加途径。A microwave irradiation heating ion-exchange method was used to increase the mesopore volume of Chinese natural zeolite. The pore size distribution （PSD） of sodium-modified Chinese natural ze- olite was evaluated by nonlocalized density functional theory （NLDFT）. The NLDFT model provided more details of PSD than the traditional BJH model. The microwave irradiation increased the mesopore volume of sodium-modified Chinese natural zeolite with diameter in a range of 3 - 5 nm while the heat reflux method only increased the mesopore volume for those with diameter below 3 nm. The different results from these two methods were attributed to the zeolite structure destroyed by acute friction among particles in the boiling process, which was verified by the powder-like appearance compared to the original plate-like particles af- ter microwave irradiation heating.

关 键 词：微波加热 天然沸石 非定域密度函数理论 孔径分布 

分 类 号：O647[理学—物理化学]