Ideas for Lube base oil color improvement

[1906]

We have hydrocracker unit followed by lube base oil production unit. This lube base oil unit has been operated with selective iso-dewaxing catalyst and hydro-fininshing catalyst. At the end of run, however, product lube base oil(Group III) color became a little darker. Re this matter, any body who has good idea to improve LBO color well above saybolt 30, please let me share that ideas or experiences.
Is there any facility that can increase color ? If you guys have any comments, it would be very helpful.

 

[25362]

What is the actual color level you want to bring up to Saybolt 30 ?
I have no experience with grade III base oils but I've had some with hydrotreated lubes. However, since you asked about any ideas/comments I propose trying a labtop active clay treat, or a filtration through kieselguhr, just to see if the color improves.

 

[1906]

. LBO color level we actually want is above Saybolt 30. By the way, would you please explain a little more detail re the laptop active clay test or filtration through kieselguhr. For example clay material, LHSV etc.. Thanks for the comment from 25362 and hope another comment.

 

[25362]

30+ is the lightest color level measured by the ASTM D156 Saybolt chromometer.
You didn't tell us what is the present color level.

An example of a laboratory test: assuming the kin. visc. @ 100[sup]o[/sup]C of the oil is between 4.5 and 5.5 cSt, add to the oil sample 2% w/w of an active clay (for example Tonsil) 200 mesh at, say, 70[sup]o[/sup]C, stirring for half an hour, filter and measure the color improvement if any.

If there is a color improvement, look for the oil chemistry factors that may be responsible such as nitrogen compounds, iron salts, etc.