钛精矿中Cr含量对钛白白度和亮度的影响

Influence of Cr Content in Ilmenite on Whiteness and Brightness of Titanium Pigments

以国内某企业两种型号的硫酸法钛白产品RA和RB为研究对象,考查了钛白初品中Cr含量对初品白度和亮度的影响规律;对此两种产品对应的两种钛精矿原料所含Cr在工序中的走向和分布以及对钛白初品质量的影响进行了深入研究,分析Cr含量不同的钛精矿对钛白产品白度和亮度影响机理,在此基础上,对生产线RA和RB两种产品的白度、亮度差异原因进行了分析。认为:钛白初品的白度和亮度值随着其中Cr含量的增加而降低,且Cr含量高于20×10-6时,初品的白度和亮度迅速下降。钛精矿中Cr含量越高,钛液中Cr含量就越高,但Cr在偏钛酸和初品中的残留量一定;钛液中Cr含量高,易造成Cr对偏钛酸的晶格掺杂,从而影响初品的白度和亮度。

Taking the two kinds of titanium white RA and RB produced by sulphate process in a domestic corporation as research targets,the influence of Cr content on whiteness and brightness of the crude titanium white pigments was studied. For the corresponding A（ raw materials of RA） and B（ raw materials of RB） ilmenite,the Cr distribution in the different working procedures and its influence on the qualities of titanium white pigments were deeply researched,and the mechanism was analyzed. Based on these results,there was also analysis on the reasons caused the differences of whiteness and brightness between RA and RB. It is indicated that both the whiteness and brightness of crude titanium white pigments decrease with increasing Cr content,and the tendency becomes sharp when the Cr content exceeds 20 ×10- 6. The more Cr in ilmenite,the higher Cr content in titanyl sulfate solution,and the residue content of Cr in meta- titanic acid keeps the same with that in crude titanium white. Furthermore,with a high content of Cr in titanyl sulfate solution,it is easy for the doping of Cr into the lattice of meta- titanic acid which affects the whiteness and brightness of crude titanium white pigments.