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As a triphenylmethane dye, crystal violet is one of high toxicity, teratogenicity, carcinogenicity,mutagenicity substances. The crystal violet wastewater generated from the industry has caused seriouspollution to water. In addition, crystal violet could transform into much toxicity compound which called asrecessive crystal violet. Therefore, it is very important to removal crystal violet from wastewater andprevent it flow into natural water body.In the present work, the simulated wastewater, crystal violet dye solution was treated by ozone,ultrasound compound with ozone, amino-silica, respectively.（1） The degradation kinetics of crystal violet oxidized by ozone in aqueous was studied. The factorswhich affected the reaction rate, including the initial concentration of crystal violet, pH value, ozone dosage,reaction temperature and inorganic cations and anions, were investigated. The study results showed thatafter120min, the degradation ratio of COD （Chemical Oxygen Demand） could be more than90%under the reaction conditions of the initial concentration of crystal violet0.88mmol L-1, pH10.0, ozonedosage9.06×10-5mol min-1and temperature25℃. The degradation process was conforms to the first orderkinetics. According to experimental results and the data have been reported in literature, Crystal violet maybe mainly degraded to various de-methylation primary and secondary aromatic amines by OH and ozone,and finally oxidized to small molecule compounds.（2） The degradation of crystal violet in aqueous solution by combined ultrasound （US） and ozonationwere studied. The factors which affected the reaction rate, including the pH value, ultrasound power,ultrasound frequency, ozone gas flow rate and reaction temperature, were investigated. The results showedthat there are synergistic enhancement effect between ultrasound and ozone. When the concentration ofcrystal violet was200mg L-1, the degradation of TOC （Total Organic Carbon） could be more than89%,under the conditions of ultrasound power200W, ultrasound frequency30kHz, solution pH10.0, ozone gasflow rate0.4L min-1and reaction temperature25℃, after90min treatment, and the pseudo-first-orderreaction rate constant was calculated as2.38×10-2min-1.（3） Adsorption of crystal violet from aqueous on to amino silica has been investigated as a function of parameters such as aqueous pH, temperature, amino silica dose, contact time, agitation speed and initialcrystal violet concentration using experimental design and response surface methodology. The modelfunction was investigated by Analysis of variance, the result showed that the quadratic polynomial equationmodel is highly significant, and it can predict the removal rate of crystal violet under unknown conditions.The optimum conditions were obtained as temperature33℃, amino silica dosage0.35g, contact time64min and agitation speed230r min-1.
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