鋅結合多壁碳奈米管複合二氧化鈦降解多氯聯苯之研究

The degradation of PCBs using zinc and titanium dioxide composite with carbon nanotubes photocatalyst

楊紘權(Hung-chuan Yang)

指導教授 ： 林耀堅

國立屏東科技大學/工學院/環境工程與科學系所/碩士(2016年)

摘要

近年來光催化氧化程序是具有潛力的的高級氧化程序之一，使用的光觸媒多以二氧化鈦為主，主要是二氧化鈦的價格相對便宜、化學安定性與氧化能力強而受到青睞。亞甲基藍為一種普遍的染料，能在很多物質表面產生吸附作用，常被用於光觸媒分解實驗中，為研究調查之對象。多氯聯苯具高穩定性、不易被生物分解且易累積於脂肪中之特性，排放至環境中會因生物濃縮及生物放大，危害人體健康及破壞環境生態。本研究以溶膠-凝膠法製備鋅結合二氧化鈦複合碳奈米管光觸媒，並比較純TiO2、TiO2/C30、TiO2/C60、Zn-TiO2/C30和Zn-TiO2/C60改質光觸媒之光催化能力，使其提高可見光區域之利用，進一步探討處理亞甲基藍與PCBs水溶液光解效能之研究。

自製光觸媒以場發射掃描式電子顯微鏡對觸媒進行表面型態的觀察；X-ray繞射分析儀分析觸媒之礦相及能量逸散光譜儀進行觸媒元素百分比分析，證實本研究自製光觸媒皆以銳鈦礦相型為主要優勢礦相。從光降解實驗得知，因為光強度的關係(自然日光721 W/m2>氙燈254 W/m2>可見光121 W/m2)，所以亞甲基藍試驗中於自然日光照射下有最佳的光催化效果，其中以600℃中的TiO2/C30、TiO2/C60和Zn-TiO2/C60光催化效果最佳。以上述實驗最佳條件進行持久性試驗，結果顯示Zn-TiO2/C60於試驗5天後具有96.2 %的降解率，且為一個可重複利用之觸媒，再以Zn-TiO2/C60對多氯聯苯於自然日光下進行降解，光催化降解於光照時間2小時後漸達趨緩，最終去除率為57 %。

關鍵字

二氧化鈦 ； 碳奈米管 ； 光觸媒 ； 亞甲基藍 ； 多氯聯苯

並列摘要

In recent years, photocatalytic oxidation procedure is one of the advanced oxidation process for the treatment of pollutants. Photocatalysts used include titanium dioxide that is relatively cheap with high chemical stability and oxidative capability. Methlene blue is a common dye, and its high adsorption ability takes place with the large surface of materials. It is commonly used for photocatalytic decomposition experiments due to decolorization. Polychlorinated biphenyls (PCBs) have been widely used in industries that are highly stable man-made organic matters. However, PCBs are not easily biodegradable, a group of persistent organic pollutant. When PCBs released to the environment through the transportation of atmosphere, due to bioconcentration and biomagnification, endanger human health and damage the environment. In this study, the sol-gel method was used to bind zinc and carbon nanotube in titanium dioxide photocatalyst composite, pure TiO2, TiO2/C30, TiO2/C60, Zn-TiO2/C30 and Zn-TiO2/C60 those were compared on catalytic ability of the photocatalyst. With the improved adsorption of the visible light region, the methylene blue and PCBs aqueous were further investigated on the photolysis efficacy of treatment.

The photocatalysts were observed using field emission scanning electron microscope (FE-SEM) on the catalyst surface patterns; X-ray diffraction analyzer (XRD) analysis of the crystal phase catalyst and elemental analysis using energy dissipation spectroscopy (EDS). This study confirmed that the prepared photocatalyst showed that anatase type is the major crystal phases. Experimental results demonstrated the efficiency of photodegradation corresponding to the relationship between the intensity of light (natural sunlight 721 W/m2> xenon lamp 254 W/m2> visible 121 W/m2). Therefore, methylene blue test using natural sunlight, which in 600℃ TiO2/C30, TiO2/C60 and Zn-TiO2/C60 has the best photocatalytic effect. The optimum conditions durability test results show 96.2% degradation rate after 5 days using Zn-TiO2/C60. PCBs were degraded (57%) in natural sunlight after 2 hours of light exposure.

並列關鍵字

titanium dioxide ； carbon nanotubes ； photocatalysts ； methylene blue ； polychlorinated biphenyls

參考文獻

鄧資騰，2012以發光二極體結合鉍/二氧化鈦光觸媒提高可見光光催化效能之研究，碩士論文，國立屏東科技大學，環境工程與科學系，屏東。

游非庸、黃媛偵、黃惠蓉，2005，「磷酸對Fenton程序脫色之影響」，蘭陽學報第四期，第7-14頁。

游淞仁，2011，以單、多壁碳奈米管複合TiO2光催化效率之評估，碩士論文，國立屏東科技大學，環境工程與科學系，屏東。

高妤秦，2002，多氯聯苯/呋喃對女性高暴露族群之生殖健康效應，國立成功大學，環境醫學研究所，碩士論文，台南。

林聖凱，2005，以微波電漿火炬製備可見光光觸媒之研究，碩士論文，私立中原大學，化學工程研究所，桃園。