奈米可見光光觸媒之製備及其應用於水中染料之光催化分解

Preparation of nanometer-sized visible-light photocatalyst for the photocatalytic decomposition of dyes in water

陳詩淵(Shr-yuan Chen)

指導教授 ： 林文崇

崑山科技大學/工程學院/環境工程研究所/碩士(2007年)

https://doi.org/10.6828/KSU.2007.00065

摘要

由於各種工業大量的使用各式各樣的合成染料，且有很大比例的染料被排入廢水中，污染了我們的環境！而這些染料中有絕大部分難被微生物給分解，亦難以傳統的化學氧化劑予以氧化破壞。故本研究探討以光催化的方法將水中的染料－亞甲基藍予以破壞、降解。
本研究為應用溶膠-凝膠法，以配製出二氧化鈦粉末，並添加不同莫耳比例的Fe、Ag或Cr 金屬離子以進行二氧化鈦粉末的改質，目的為利用添加不同莫耳比例的Fe、Ag或Cr金屬離子將二氧化鈦的光吸收特性由紫外光的吸收範圍轉移到可見光範圍，來增進光觸媒於可見光的照射下對亞甲基藍的分解效力。
結果得知以Fe/Ti = 0.1 mole %，在500 ℃下煅燒、Ag/Ti = 2 mole %，在700℃下煅燒和Cr/Ti = 0.4 mole %，在300 ℃下煅燒之改質二氧化鈦比未改質二氧化鈦性能來的佳！經紫外光-可見光光譜分析，明顯都有往可見光的吸收範圍移動，並在本研究系統中可經由十小時可見光的照射，將水中20 ppm的亞甲基藍破壞降解掉16~25 %。

關鍵字

染料 ； 溶膠-凝膠 ； 二氧化鈦 ； 光觸媒 ； 可見光

並列摘要

Large amounts of synthetic dyes are used for various industrial applications. A significant proportion appears in the form of wastewater and is spilled into the environment. Most of them are recalcitrant to biodegradation and conventional chemical oxidation using oxidants. In this work, the photocatalytic decomposition of methylene blue in water was studied.
Titanium dioxide powders modified with specific metal or metal oxide could be used as photocatalyst with visible light activity. In this work, various nanometersized titanates has been prepared from alkoxide solutions containing polyethylene glycol (PEG) via the sol-gel method and by calcination of a mixture of Fe(NO3)3 [AgNO3, or Cr(NO3)3] and titanium dioxide sol solution. And they were used as photocatalysts with visible light activity in the reaction of methylene blue decomposition in water.
The more active modified titanium dioxide photocatalysts were obtained by adding 0.1 mole % Fe+3, 2.0 mole % Ag+, or 0.4 mole % Cr+3 and calcining at 500 ℃, 700 ℃, or 300 ℃, respectively. About 16~25 % of 20 ppm methylene blue in water could be decomposed under visible light irradiation with the modified photocatalyst content of 0.33 g dm-3 for 10 hours.

並列關鍵字

Dyes ； Photocatalyst ； Visible light ； Titanium dioxide ； Sol-gel

參考文獻

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