發(fā)布時(shí)間：2018-01-14 02:25

  本文關(guān)鍵詞：微納米分級(jí)有序介孔硅酸鎂的制備與性能研究　出處：《內(nèi)蒙古大學(xué)》2017年碩士論文　論文類型：學(xué)位論文

  更多相關(guān)文章： 介孔材料 微納米硅酸鎂 水熱法 吸附

【摘要】：硅酸鎂具有獨(dú)特的晶體結(jié)構(gòu)和高比表面積的多孔性,可以提供特異的分子場(chǎng)作用力,形成多種類型的吸附中心,在吸附分離領(lǐng)域中有巨大的應(yīng)用潛力。如何提高硅酸鎂的比表面積和孔體積進(jìn)而提高其吸附性能,已成為該領(lǐng)域的研究重點(diǎn)。本文通過水熱法來構(gòu)筑微納米分級(jí)介孔硅酸鎂,研究其對(duì)染料分子和鉛離子的吸附性能,主要研究?jī)?nèi)容如下:1.微納米分層結(jié)構(gòu)硅酸鎂利用介孔二氧化硅SBA-15為模板,以氯化鎂為鎂源,通過犧牲輔助模板-水熱法制備出微納米分層結(jié)構(gòu)硅酸鎂。結(jié)果表明:硅酸鎂具有微納米復(fù)合結(jié)構(gòu),表面是由納米片組成,片的厚度約為12nm,硅酸鎂的比表面積為411 m~2/g,孔體積為0.45 cm~3/g,平均孔徑為4.18 nm。微納米分層結(jié)構(gòu)硅酸鎂對(duì)亞甲基藍(lán)(MB)和羅丹明B(RhB)的最大吸附量分別為353 mg/g和227mg/g,吸附過程符合準(zhǔn)二級(jí)動(dòng)力學(xué)方程,吸附符合朗繆爾吸.附等溫模型。2.微納米有序介孔硅酸鎂通過蔗糖填充和碳化工藝,獲得碳填充的介孔氧化硅SBA-15(C@SBA-15),并將其作為輔助模板和硅源,通過水熱技術(shù)制備出微納米有序介孔硅酸鎂。結(jié)果表明:硅酸鎂具有二維六方相介孔結(jié)構(gòu),微米結(jié)構(gòu)是由納米孔道和表面的納米片構(gòu)成,比表面積為283 m2/g,平均孔徑為7.39 nm,孔體積為0.53 cm3/g,納米片的厚度約為44 nm。微納米有序介孔硅酸鎂對(duì)MB的一次和二次吸附量分別為341 mg/g和203 mg/g,表現(xiàn)出較高的吸附容量、優(yōu)異的重復(fù)利用效率和穩(wěn)定性;對(duì)鉛離子最大吸附量為417 mg/g。吸附過程滿足準(zhǔn)二級(jí)動(dòng)力學(xué)方程和朗繆爾吸附等溫模型,可以用韋伯-莫里斯內(nèi)擴(kuò)散模型描述。3.單分散微納米介孔硅酸鎂對(duì)含有表面活性劑的SBA-15進(jìn)行原位碳化,獲得分散性良好的C@SBA-15,并以此為模板和硅源,同時(shí)加入分散劑PEG200,通過犧牲輔助模板-水熱法制備出單分散微納米介孔硅酸鎂。結(jié)果表明:硅酸鎂的表面和沿著內(nèi)部孔道都充滿了片狀結(jié)構(gòu),構(gòu)成分散性良好的微納米復(fù)合結(jié)構(gòu)硅酸鎂,其比表面積為424 m2/g,平均孔徑大小為50 nm,孔體積為0.53 cm3/g;對(duì)MB的最大吸附量為208.5 mg/g,吸附過程符合準(zhǔn)二級(jí)吸附動(dòng)力學(xué),吸附容量可以用朗繆爾等溫吸附模型分析。實(shí)驗(yàn)表明這種以介孔氧化硅材料為模板和硅源制備的微納米介孔硅酸鎂具有較高的比表面積和大的孔體積,制備方法簡(jiǎn)單易操作,對(duì)有機(jī)陰離子染料和重金屬離子有很強(qiáng)的吸附作用,并且作為吸附劑可以多次循環(huán)使用,是一種性能優(yōu)異的吸附材料。
[Abstract]:Magnesium silicate has unique crystal structure and high surface area porosity, which can provide specific molecular field force and form a variety of adsorption centers. It has great application potential in the field of adsorption and separation. How to improve the specific surface area and pore volume of magnesium silicate and improve its adsorption performance. In this paper, micro and nano-sized mesoporous magnesium silicate was constructed by hydrothermal method to study the adsorption properties of dye molecules and lead ions. The main contents of the study are as follows: 1. The micro and nano layered magnesium silicate uses mesoporous silica SBA-15 as template and magnesium chloride as magnesium source. Magnesium silicate was prepared by sacrificial assisted template-hydrothermal method. The results show that magnesium silicate has a micro-nano composite structure, and the surface is composed of nanochips, the thickness of which is about 12 nm. The specific surface area of magnesium silicate is 411mg / g and the pore volume is 0.45 cm~3/g. The average pore size is 4.18 nm. The maximum adsorption capacity of microlayered magnesium silicate for methylene blue blue (MBB) and Rhodamine Bhh (RhB) is 353 mg/g and 227 mg / g, respectively. The adsorption process accords with the quasi-second-order kinetic equation and the adsorption accords with Langmuir sorption. 2. The ordered mesoporous magnesium silicate is filled with sucrose and carbonized by sucrose. Carbon filled mesoporous silicon oxide SBA-15 was obtained and used as an auxiliary template and silicon source. The results show that magnesium silicate has two-dimensional hexagonal mesoporous structure and micron structure is composed of nano-pore and surface nanochip. The specific surface area is 283m2 / g, the average pore size is 7.39nmand the pore volume is 0.53 cm3/g. The thickness of nanocrystalline was about 44 nm. The primary and secondary adsorption capacities for MB were 341 mg/g and 203mg / g, respectively, showing a high adsorption capacity. Excellent reuse efficiency and stability; The maximum adsorption capacity of lead ion is 417 mg / g. The adsorption process meets the quasi-second-order kinetic equation and Langmuir adsorption isotherm model. Weber-Morrisnay diffusion model can be used to describe .3.Mono-dispersed micro-mesoporous magnesium silicate in situ carbonization of SBA-15 containing surfactants to obtain a good dispersion of CSBA-15. It is used as template and silicon source, and dispersant PEG200 is added at the same time. The monodisperse micro-mesoporous magnesium silicate was prepared by sacrificial assisted template-hydrothermal method. The results showed that the surface and inner channels of magnesium silicate were filled with flake structure. Magnesium silicate with good dispersibility has a specific surface area of 424 m2 / g, an average pore size of 50 nm and a pore volume of 0.53 cm / g. The maximum adsorption capacity of MB was 208.5 mg / g, and the adsorption process was in accordance with the quasi-second-order adsorption kinetics. The adsorption capacity can be analyzed by Langmuir isothermal adsorption model. The experimental results show that the micromesoporous magnesium silicate prepared by using mesoporous silica as template and silicon source has high specific surface area and large pore volume. The preparation method is simple and easy to operate, has strong adsorption on organic anionic dyes and heavy metal ions, and can be used as adsorbent for many times, so it is a kind of excellent adsorption material.
【學(xué)位授予單位】：內(nèi)蒙古大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2017
【分類號(hào)】：TQ132.2;TB383.1

【參考文獻(xiàn)】

相關(guān)博士學(xué)位論文 前1條

1 楊毅;納米/微米功能復(fù)合材料的制備及應(yīng)用研究[D];南京理工大學(xué);2003年

相關(guān)碩士學(xué)位論文 前1條

1 李蒙蒙;納/微米結(jié)構(gòu)氧化鋁復(fù)合材料的制備和性能研究[D];吉林大學(xué);2013年

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本文編號(hào)：1421631