【作者】 周乐舟；

【导师】 周方钦；

【作者基本信息】 湘潭大学 ， 分析化学， 2008， 硕士

【摘要】 本论文在查阅大量中外文献资料的基础上,通过深入、系统的试验研究,根据中孔分子筛具有可调的孔径、可控的行貌、结构组成等特点,自行合成了中孔分子筛并制作成一种新型的吸附材料对有害金属离子进行分离富集,分别研究了汞、镉、铬等有害金属离子在中孔分子筛上的分离富集行为,运用原子光谱法测定痕量有害金属元素,由此建立了简单、准确、高效、高选择性、高灵敏度的分析痕量有害金属离子的新方法。拓展了中孔分子筛在分析化学领域中的应用。全文共分四章,主要内容如下:第1章:综述了近年来分离富集技术和吸附材料在原子光谱检测的中应用。重点介绍了新型吸附材料-中孔分子筛产生的历史、特性及在分离富集中的应用,以及中孔分子筛的研究进展。第2章:以正辛胺为模板剂合成了有机—无机介孔材料,以此作为分离预富集材料,以原子荧光法作为测试手段,建立了测定痕量汞的一种新方法,探讨了中孔分子筛吸附汞的原理以及溶液pH值、温度、洗脱条件及干扰离子对汞分离富集的影响,该方法测定汞的检出限达1.89×10-9 g/L,相对标准偏差为2.69%,线性范围为0.005 ng/mL～5 ng/mL,相关系数r=0.9992,加标回收率在95.3%～104.5%之间。此法应用于环境水样中痕量汞的测定,结果满意。第3章:用合成的中孔分子筛P123–SH作为镉的分离富集新材料,以原子吸收光谱法作为测试手段,建立了测定痕量镉的新方法,探讨了中孔分子筛P123–SH吸附镉的原理以及溶液pH值、温度、洗脱条件及干扰离子对镉分离富集的影响,该方法的检出限为0.12μg/L,加标回收率在96.5%～103.1%之间,对50μg/L的Cd2+溶液平行测定7次,RSD=2.1%。此法已成功地应用于环境水样中痕量镉的测定。第4章:采用嫁接法制备了一种新型的中孔分子筛SBA-15(NH2),以此为吸附材料,以火焰原子吸收光谱为测试手段,研究了中孔分子筛SBA-15(NH2)材料在动态条件下对环境样品中痕量铬进行形态分析。探讨了微柱中孔分子筛吸附铬的原理以及溶液的pH值、温度、采样时间、采样速度、洗脱条件及干扰离子对铬在线分离富集的影响,由此建立了测定痕量铬的新方法,该方法线性范围为0.00012~2.0μg/mL,线性回归方程A=0.1198C+0.0545,检出限为0.10 ng/mL,相对标准偏差为2.8%,加标回收率在99.0%~104.0%之间,该方法用于实际水样中痕量铬的形态分析,结果满意。更多还原

【Abstract】 On the basis of numerous references, through in-depth and systemic studied, mesoporous molecule-sieve was chosen to be studied because its aperture and shape can be controlled or its derivative’s characteristics and the existing state of being studied at home and abroad. Mesoporous molecule-sieve firstly has been synthesized and then impregnated, loaded or bonded on the carrier to prepare a new type of adsorbent material which was applied to separate/enrich harmful metal ions. The separation and concentration behavior of Hg、Cd、Cr ions had been studied respectively, and then new methods for analysis and determination by FAAS of trace heavy harmful metal ions have been established. The methods were simple / accurate and highly selection. At the same time, the field of mesoporous molecule-sieve applied was enlarged.The major contents include four parts, there are described as follows:1. The methods of separation/preconcentration and kinds of adsorption materials in atomic adsorption spectrometry detemination were reviewed. The characteristics and application in separation/preconcentration of new adsorption material- mesoporous molecule-sieve were introduced in detail.2. A new functiontalized organic-inorganic mesoporous material has been studied on preconcentration and determination of trace mercury. Determination of trace mercury by atomic fluorescence spectrometry (AFS) after perconcentration on supported this material was elutioned with thick HCl. The linear range was 0.005~5 ng/mL. The detection limit was 1.89×10-9 g/L(3σ). The RSD was 2.69﹪(n=11 , c=0.5 ng/mL). The recoveries of mercury were 95.3~104.5﹪. The method has been applied for determination of trace mercury in water samples with satisfactory results.3. A new method of determination of trace cadmium with mesoporous molecule-sieve P123-SH material by flame atomic absorption spectrometry (FAAS) was reported. The linear range was 0.0005～0.1mg/L. The detection limit was 0.12μg/L (3σ,n=11). The recoveries of cadmium were 102%~104%.The RSD was 2.13%(n=7, c=0.05 mg/L). The method has been applied for determination of trace cadmium in water samples with satisfactory results.4. Mesoporous molecule-sieve SBA-15(NH2) was synthesized through grafted mothed, use SBA-15 and 3-aminopropyltriethoxysilane as reagent, SBA-15(NH2) was synthesized at strict conditions in our laboratory. A PTFE micro column packed with SBA-15(NH2) was used in FI (flow injection)-FAAS (flame atomic adsorption spectrometry) system for the determination trace Cr forms in environment sample. The linear range was 0.0002~2.0μg/mL.The detection limit was 0.10 ng/mL. The linear equation was A=0.1198C+0.0545(C:μg/mL,r=0.9978). The RSD was 2.8%. The recoveries of Cr(Ⅲ) was 99.0%~104.0%. The method has been applied for the determination of trace Cr forms in environmental and biological samples with satisfactory results.更多还原