wherein a weight ratio in the mixture of {TAIL ~ the first heavy oil fraction} relative to {HEAD ~ the deasphalting residue} is from 30:70 to 70:30, and further comprising up to 10 wt % of an alkyl substituted aromatic sulfonic acid, 
wherein a weight ratio in the mixture of { TAIL ~ the first heavy oil fraction } relative to { HEAD ~ the deasphalting residue } is from 30:70 to 70:30 , and further comprising up to 10 wt % of an alkyl substituted aromatic sulfonic acid ,
OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH