利用二氧化鈦／氫氧磷灰石光觸媒處理水中酚之研究

Study on the Treatment of Phenol in Aqueous Solution via TiO2/Apatite Photocatalyst

本研究以溶膠－－凝膠法製備二氧化鈦(TiO2)及氫氧磷灰石(Apatite)，利用二氧化鈦經紫外光照射後產生氧化作用，以及磷灰石對有機物可吸附之特性將二者結合，以酚為反應物，使用不同比例二氧化鈦／磷灰石所合成之觸媒，由上述反應物去除率篩選最適之TiO2/Apatiet光觸媒及最適之觸媒添加量。從實驗結果得知，當觸媒中TiO2含量高於Apatite時，對水中的汙染物去除率也會較高，反之則相反。另外，從BET分析發現添加適量的聚丙烯可以增加磷灰石的比表面積，最適之磷灰石／聚丙烯比例為1:1。由分析實驗結果得知，TiO2/Apatiet光觸媒在二氧化鈦／鱗灰石合成比例為5:1時，對水中酚反應效果為最佳，最適觸媒添加量為0.75g/L。在前述最佳觸媒及最適添加量下，常溫、常壓下反應6小時，則100 mg/L酚轉化率可達45%，COD去除率則為24%，而50mg/L酚在常溫、常壓下反應4小時，則酚轉化率可達55%，COD去除率則為35%，另實驗也發現，當紫外光強度提高時，觸媒對水中有機物的去除效果也增加。

This study aimed at removing phenol in aqueous solution via photo catalysis. A more efficient photo catalyst, i.e. TiO2/Apatite, was synthesized by the sol-gel method. The improved efficacy of TiO2/Apatite may be attributed to the combination of photo catalytic capability of TiO2 and adsorption capability of Apatite. Removing efficiency of phenol was based to screen for the optimal catalyst loading and composition of TiO2/Apatite. The results show that Apatite has the most BET surface area as it was prepared at Apatite/pp=1:1. Moreover, for removing phenol, the optimal ratio of TiO2/Apatite is 5:1. The most suitable catalyst loading is about 0.75 g/L for this organic tested. Under the above-mentioned optimal reaction a condition, the following efficiency was obtained. For 100 mg/L phenol, 45% phenol conversion and 24% COD removal was achieved after 6 hrs reaction. Besides, UV radiation intensity was also relevant to the phenol removing efficiency. Higher radiation intensity confers to higher efficiency