Preparation Of Water Purification Agents Of Titanium Ferric And Application In Wastewater

Two new types of water purification agents of titanium and ferric(M-PTF and I-PTF) were prepared using the raw materials of “metatitanic acid waste” from titanium white production process and ilmenite, respectively. The optimum preparation parameters of M-PTF and I-PTF were obtained with orthogonal experiment method. Surface morphology, crystal structure, bonding structure and composition of these two coagulants were investigated by scanning electron microscope(SEM), infrared spectrum(IR), X-ray diffraction(XRD), fluorescence spectrometer instrument, and so on. And coagulation characteristics of M-PTF and I-PTF was studied compared with that of polyaluminium chloride(PAC) in treating sewage and simulate dyeing wastewater. And coagulation mechanism of this kind of coagulant was also simply discussed.The microscopic characterization experimental results expressed that M-PTF and I-PTF were composed of many crystals and amorphous polymer of metal complex. The surface morphology of M-PTF presents a sort of spacial network structure, in comparision with of lamellar structure of I-PTF. These two coagulants have larger specific surface area and strong bridging and sweeping ability, leading to their excellent coagulation effect.The influences of dosages of these two coagulants and pH value of raw water samples on coagulation effect were studied using sewage and simulate dyeing wastewater as tested wastewater samples, compared with that of PAC. The results showed that the optimum doses of M-PTF and I-PTF were lower than that of PAC.Dealing with sewage, the M-PTF removal rate of turbidity, color and COD at the optimum doses of 144mg/L were 96%, 93% and 71% respectively,while the I-PTF removal rate of turbidity, color and COD at the doses of 216 mg/L were 91%, 89% and 71% respectively. Dealing with simulate dyeing wastewater, the I-PTF removal rate of turbidity and color at the doses of 72mg/L were 97%, 97% respectively, while the M-PTF removal rate of turbidity and color at the doses of 96 mg/L were 98%, 96% respectively.However, the M-PTF and I-PTF removal rate of COD increased as the change of the dose and reached 65%,55%, respectively at the doses of 144mg/L. And the coagulation effect of M-PTF and I-PTF in alkaline conditions was better than that in acidic conditions. Floc sedimentation experiments were studied in treating sewage using M-PTF, I-PTF, and PAC, respectively. The results showed that M-PTF and I-PTF had better floc sedimentation performance, faster settling velocity and denser flocs that PAC.Finally, the coagulation mechanism of this new type of water purification agents was discussed according to the microscopic characterization and coagulation performance based on the theory of traditional coagulation theory.