05173172 is referenced by 22 patents and cites 5 patents.

Hard asphalts exhibiting acceptable penetration and low temperature properties can be produced from vacuum residua from which such hard asphalts are not normally obtainable via typical vacuum distillate such as that derived from Arab Light crude and/or feeds substantially comprising Arab Light-type crudes by ultrafiltering the residua through a membrane.

Title
Production of hard asphalts by ultrafiltration of vacuum residua
Application Number
7/746542
Publication Number
5173172
Application Date
August 19, 1991
Publication Date
December 22, 1992
Inventor
John A Thompson
Lady Smith
CA
Brian B Adams
Sarnia
CA
Agent
Joseph J Allocca
Assignee
Exxon Research and Engineering Company
NJ, US
IPC
C10C 1/00
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