Methods of separating aromatic compounds from lube base stocks

A method for separating an aromatic compound from a lube base stock, the method comprising contacting a lube base stock containing an aromatic compound with an organosilica material, which is a co-polymer of:

• (a) a monomer of Formula [Z1OZ2OSiCH2]3 (I), wherein Z1 and Z2 each independently represent a hydrogen atom, a C1-C4 alkyl group, or a bond to a silicon atom of another monomer;
• and
• (b) a cyclic polyurea monomer of Formula
• wherein each R1 independently is a X1OX2X3SiX4 group, wherein each X1 represents a hydrogen atom, a C1-C4 alkyl group, or a bond to a silicon atom of another monomer;
• X2 and X3 each independently represent a hydroxyl group, a C1-C4 alkyl group, a C1-C4 alkoxy group, or an oxygen atom bonded to a silicon atom of another monomer;
• and each X4 represents a C1-C8 alkylene group bonded to a nitrogen atom of the cyclic polyurea monomer.