Effe ct of some operatio nal parameters on d iscoloration of Aci d Blue ۱۱۳ via nano TiO۲ stabilized on concrete be d in photocatalytic process

Textile dyes are one of the m ain sources of environmental pollution. More than ۴۰ percents of consumed dyes, in different dyeing proc esses are r eleased to wastewater. Dyes chang e the color of water and prevent light diffusion, disturbing photosynthetic and leads to destruction of aquatic ecosystem [۱-۲]. Mo dern comm ercial dyes are very stable and t hey contain high comp osition ratio of aromatic rings. Azo dyes represent the largest class of dyes. The r elease of these compounds into the environment is undesir able, not only because o f their color, but also because many azo dyes and their bre akdown pro ducts are to xic and/or mutagenic t o life. Thus, wastewater containing s ynthetic az o deys is co nsidered serious warning for environ ment and removal of these pollutants has been attended in several researches [۳]. Since conventional treatment methods including physical, chemical and biological, such as filtration, adsorption, coagulation and chemical oxidation are u nable to degradation of these pollu tants as much as environmental standards [۴]. Recently, th e application of advanced oxidation methods[۵], such as pho tocatalytic reactions have been exp anded for removing of toxic and non-biodegradable pollutions. Semic onductor na nostructures play an imp ortant role i n developing smart materials that c an simultane ously sense and destroy harmful chemical contaminants such as dyes. Some reason s for these particular properties are break down of whole pollutio ns, removing of various types of pollutions in short time, e xcreting of residuals easily and ability to carry out in room temperature and pressure [۶-۷].

Keywords:

Titanium dioxide nanoparticl e , COD , DO , ORP , AB۱ ۱۳.