Pentachlorophenol is a phenolic compound that was chlorinated. Pentachlorophenol very toxic for our breath, cause dermatitis on skin and more toxic than inorganic solvent. Pentachlorophenol waste almost dissolvable in water so degradation process is very hard. Some ways have been done to solve biological waste problem, but not efficient enough. For example, active carbon just involve pollutant absorption without decomposition process. Chemical oxidation process can’t decomposition all of organic compound be carbon dioxide and water, and have been used in high concentration waste. Many century ago, scientist success to describe phenomenon photocatalytic in surface of metal-oxide semiconductor. Firstly, have been issued by Renz in 1921 until 1960, and not responding by scientist. Photocatalytic semiconductor popularity increase since publication Akira Fujishima in Nature magazine was issued in 1972. He was reported decomposition water be oxygen and hydrogen used single crystal TiO2 with input UV light in low energy. First research, TiO2 have been used as photocatalytic suspension system. Nowadays, the uses TiO2 as photocatalytic is used in thin plate shape, which is immobilization TiO2 to many kinds of supported material like fiber, glass, silica, and titanium plat.
Titanium dioxide to degrade pentachlorophenol