| The rapid development of science, technology and proceeding industrializationleads to the consumption and draining of heavy metals and organic substance. Thepollution caused by heavy metals and poisonous organic substance become more andmore serious. The accurate determination of trace element in geological, biologicaland environmental samples is very important in analytical chemistry. Although manyinstrument analysis methods have been developed recently and reached trace level orsuper trace level sensitivity, the direct analysis is still difficult because of the highcomplexity of samples and severe interference caused by matrix effects. So, variouspre-treatment procedures are necessary before the more accurate measurement byanalytical instruments. It is obvious that the pre-treatment procedures of traceelements depend on appropriate separation methods and different functionaladsorption materials with higher selectivity and adsorption capacity. This papermainly described the preparation of several adsorption materials based on thepre-concentration and separation of trace components. The behaviors of thesematerials that have high selectivity for targets have been studied systematically anddetailedly. At the same time, study on nano-scale nickel hydroxide-CNTs composedmaterial used as electrode material has been done by me. The more detailed noveltyof this work can be categorized as follows:1. The imprinted and non-imprinted amino-functionalized silica gel adsorbents forFe(Ⅲ), Ni(Ⅱ) and Al(Ⅲ) were obtained by a surface imprinting technique forselective extraction of Fe(Ⅲ), Ni(Ⅱ) and Al(Ⅲ) prior to its determination byICP-AES. The results are: (1) Compared with the traditional solid sorbents andnon-imprinted sorbent, the Fe(Ⅲ)-imprinted amino-functionalized silica gel adsorbentexhibited excellent selectivity and adsorption capacity for Fe(Ⅲ). The maximumstatic adsorption capacity of the Fe(Ⅲ)-imprinted and non-imprinted sorbent forFe(Ⅲ) was 25.21 and 5.10 mg g-1, respectively. The largest selectivity coefficient of the Fe(Ⅲ)-imprinted sorbent for Fe(Ⅲ) in the presence of Cr(Ⅲ) that is the sameconcentration with Fe(Ⅲ) was 451. The relatively selective factor (ar) value ofFe(Ⅲ)/Cr(Ⅲ) was 49.9, which were greater than 1. The detection limit (3σ) of themethod was 0.34μg L-1. The relative standard deviation (R.S.D.) was 1.5 %. Theproposed method has been successfully applied to the determination and speciation ofiron in biological and water samples with satisfactory results. (2) Compared with thetraditional solid sorbents and non-imprinted sorbent, Ni(Ⅱ)-imprinted sorbent presentshigher selectivity and adsorption capacity for Ni(Ⅱ). The maximum static adsorptioncapacity of the ion-imprinted and non-imprinted sorbent for Ni(Ⅱ) was 12.61 and 4.25mg g-1, respectively. The relatively selective factor (αr) values of Ni(Ⅱ)/Cu(Ⅱ),Ni(Ⅱ)/Co(Ⅱ), Ni(Ⅱ)/Zn(Ⅱ) and Ni(Ⅱ)/Pd(Ⅱ) were 45.99, 32.83, 43.79 and 28.36,which were greater than 1. The detection limit (3σ) of the method was 0.16 ng mL-1.The relative standard deviation of the method was 1.48 %. The method wassuccessfully applied to the determination of trace nickel in plants and water sampleswith satisfactory results. (3) Compared with the traditional solid sorbents andnon-imprinted sorbent, Al(Ⅲ)-imprinted sorbent presents higher selectivity andadsorption capacity for Al(Ⅲ). The maximum static adsorption capacity of theion-imprinted and non-imprinted sorbent for Al(Ⅲ) was 11.46 and 6.28 mg g-1,respectively. The relatively selective factor (αr) value of Al(Ⅲ)/Cr(Ⅲ) was 6.73. Therelative standard deviation of the method was 3.2 %. The detection limit (3σ) of themethod was 0.36 ng mL-1.2. A molecularly imprinted polymer was prepared by molecular imprintingtechnique using aerylamide (AA) as monomer, curcumin as template molecule, alarge excess of pentaerythritol triacylate (PETRA) as the cross-linking agent and 2,2-Azobisisobutyronitrile (AIBN) as the initiator. The bulk polymer obtained wasinvestigated in equilibrium binding experiments to evaluate the molecular recognitionand binding characteristics of the curcumin molecularly imprinted polymer. Thesubstrate selectivity of imprinted polymers and non-imprinted polymers wereinvestigated. The results showed that the imprinted polymers exhibited much higher affinity for curcumin among the tested compounds. It is possible to be a goodadsorption and binding material in the selective enrichment and determination of tracecurcumin in complex biosamples.3. Nanometer Ni(OH)2 were prepared by chemistry-deposition method with addingthe buffer solution and surfactant. Firstly, carbon nanotubes (CNTs) were dispersed inNaOH solution, then CNTs were chemically synthesized with nanometer Ni(OH)2. Inthis experiment, 10-20 nm, 20-40 nm, 60-100 nm of 2 wt%, 5 wt%, 10 wt%, 25 wt%and 50 wt% CNTs were used to study the electrochemical performances ofNi(OH)2/CNTs composed electrode. The results showed that Ni(OH)2/CNTscomposed electrode presents the best performance with using 20-40 nm of 25 wt%CNTs. The specific capacity is 280 mAh/g. And the electrode using ultrasoniccondition has a better cycling stability, a higher charging efficiency, greater specificdischarge capacity, higher discharge voltage, better high-rote capability and superiorcycling stability.
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