The Study Of Pilot Scale Of Rutile Phase Nanometer Titanium Dioxide

Titanium dioxide of rutile phase has the most stable crystal structure in three main crystallographic forms of titania.Compared with anatase TiO2,rutile TiO2 has the higher refractive index,the larger the dielectric constant,the higher density and the higher hardness.In addition to non-toxic and odorless.As the result of these advantages,nano-titanium dioxide has been studied both the scientific community and industry attention since the rise of nano-materials in the late 1980s.These excellent properties of rutile TiO2 makes it been widely used in many industries.In this market context,based on the transfer of patented technology about "one kind of preparation method of titanium dioxide nano-powder of rutile phase(application date:2004.11.16;application number:200410084338.6,;Publication date:2005.6.29;Publication Number:CN1631795A).To make this technology can be applied successfully to industrial production,and to provide theoretical and practical guidance for future large-scale production,the pilot study of this paper carried out mainly from the following aspects:We magnified the feasibility analysis to the optimum condition of laboratory stage.From the verification result,we can see that the product has stable yield,reliable quality,high purity,uniform particle size and good dispersion in the laboratory stage.Meanwhile,the technology has repeatability.Meet the technical feasibility analysis to the pilot study.We account the costs(include fixed asset costs,direct material costs,fuel and power costs,payroll and benefits,waste disposal charges,other charges,etc.)and profits of pilot study.The costs of per ton product is 61,000.The gross profit of per ton product is about 159,000.The profit tax is 31,800.So we can see that the net profit is 127,200.The investment in equipment is 46,600.Meet the economic feasibility analysis of pilot study.After analysis,we can see that the pilot project meet feasibility analysis of the pilot study in terms of market,technology or economically.In this paper,we magnified the optimum condition of laboratory stage of rutile TiO2.The scope of amplification is 60 times.The total volume is 9L.First,We studied the influence of stirring rate on the particle size of titanium dioxide.Then we used orthogonal experiment method to study the influence of the reactant concentration ratio,precipitation formation temperature,reaction time on the yield and particle size of the product.Experimental results show that the particle size decreases and then increases with the stirring rate increases,and then the trend become slow.Obtain the optimal reaction conditions and the variation of the reaction conditions as the size of the amplification is increased.The variation is that the ratio of water and sol of titanium tetrachloride and the reaction time should be increased.Compared to the above two indicators,the effect of temperature is smaller.Because of the problem that the solid-liquid separation is difficult.The loss rate of TiO2 is high using the method of filtration.In order to reduce the settling period,we added a certain amount of water in the precipitate,and then aqueous ammonia was added slowly until the pH is up to 6.5-7.Then stand for 4 to 5 minutes,centrifuged,dried in 110℃,calcined in 500℃、750℃ and 800℃.Nanosized TiO2 particles were characterized by Scanning electron microscopy(SEM),X-ray diffraction(XRD),and the laser size distribution apparatus.