钛白粉白度影响因素分析

Analysis of Factors Affecting the Whiteness of Titanium Dioxide

以某钛白粉厂2019年全年钛白初品和成品为分析对象,统计分析了产品铁含量和金红石含量对钛白干粉白度的影响规律,在此基础上选择铁含量和金红石含量相当的不同白度样品,分别采用激光粒度仪和SEM进行激光粒度分析和SEM粒度分布分析。结果表明:产品白度随着铁含量的增加呈下降趋势,铁含量(质量分数)超过50×10-6后白度显著下降;金红石含量在97%~100%范围内,随金红石含量的增加,产品白度呈现微弱的下降趋势;随产品激光粒度粒径D50的增加,产品白度呈现下降趋势,D50<300 nm可获得较高的白度;SEM平均粒径在200~300 nm范围内,产品白度随粒径增加呈现下降趋势,随150~350 nm粒径比例增加,产品白度呈现增加趋势。平均粒径在240 nm以下,150~350 nm颗粒所占比例在75%以上时产品亨特白度可达到95以上。

Taking the original and final titanium dioxide products from a titanium dioxide factory in 2019 as the object,the influences of iron content and rutile TiO2 content on the whiteness of the product were statistically analyzed.On this basis,samples of different whiteness with similar iron content and rutile TiO2 content were selected to analyze the particle size distribution by a laser particle size analyzer and SEM,respectively.The results show that the whiteness of the product decreases with increase of the iron content,and a significant decrease of the whiteness can be found with the iron content exceeding 50 ppm.At 97%to 100%of the rutile TiO2 content,the whiteness of the product shows a slight decrease with increase of the rutile TiO2 content.With the increase of the product’s laser particle size D50,the whiteness of the product shows a downward trend,and a higher whiteness can be obtained with D50 less than 300 nm.At 200~300 nm of the average particle size by SEM,the product’s whiteness decreases with increase of the particle size,and the whiteness increases with increase of the ratio of particles of 150~350 nm.Hunter whiteness above 95 of the product can be obtained at the average particle size less than 240 nm and the proportion of particles of 150~350 nm above 75%.