在可見光照射下利用含鐵酸鋅/二氧化鈦光觸媒之粒狀活性碳在液-固流體化床內去除酸性染料之研究

Removal of Acid Dye by ZnFe2O4/TiO2-Immobilized Granular Activated Carbon in a Liquid-Solid Fluidized Bedn under Visible Light Irradiation

范國瑄(Kuo-shiuan Fan)

指導教授 ： 王榮基

大同大學/工程學院/化學工程學系所/碩士(2005年)

摘要

摘要

本研究主要探討將Zinc Ferrite/TiO2固定在粒狀活性碳(GAC)上，操作在流體化床內作光催化反應。藉由添加能隙較低的半導體改質二氧化鈦達到能在可見光下進行實驗。Zinc Ferrite/TiO2以sol-gel方法來製備，主要藥品為Titanium n-butoxide，配製後放入震盪器經過12小時反應，再經過不同的溫度煅燒而得。由XRD、SEM、EDS和DRS的分析中證實，粒狀活性碳上有尖晶石的鐵酸鋅(spin zinc ferrite)及anatase晶相的TiO2存在，且分佈在粒狀活性碳的表面上。光催化反應是以酸性染料當有機污染物作為分解對象。使用一個圓柱型壓克力流體化床反應器進行分解反應，燈源為150W的CDM-T燈管，以進行可見光光催化反應。
實驗結果顯示，含Zinc Ferrite/TiO2的粒狀活性碳觸媒在可見光下高於粒狀活性碳的吸附效率。實驗操作的變數包括:含光觸媒之活性碳粒徑、酸性染料起始濃度、與光觸媒活性碳的添加量。光催化反應經由一階動力式表示出反應常數隨著染料濃度與觸媒粒徑增加而減小;隨著光觸媒活性碳的添加量增加而上升。

關鍵字

流體化床 ； 活性碳 ； 光觸媒 ； 可見光

並列摘要

ABSTRACT

The photocatalytic oxidation of acid dye in visible light irradiation was carried out in a fluidized bed reactor.
ZnFe2O4/TiO2-immobilized granular activated carbon was employed as the photocatalysts, and the lamp (CDM-T, 150 W) was used as the light source. The fluidized bed reactor, involving contact among liquid and solid phases, has gained an increasing importance in a wide range of industrial application. ZnFe2O4/TiO2-immobilized granular activated carbons (ZnFe2O4/TiO2-GAC) with different characteristics and absorption ability were prepared by hydrolysis of Titanium n-butoxide, combined with Zinc Ferrite solution and calcinations at different temperatures. The crystalline structures and morphologies of the samples have been characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive spectrometer (EDS) and diffuse reflectance spectrum (DRS). The kinetic law for the photocatalytic degradation was determined to apparently be first-order with respect to the concentration of acid dye. The apparent first-order rate constant decreases with increasing initial acid dye concentration and catalysts particle size, as well as with decreasing ZnFe2O4/TiO2-GAC amount.

並列關鍵字

activated carbon ； fluidized bed ； photocatalyst ； visible light

參考文獻

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