F MacGregor Miller, Timothy Jay Roth, William Russell Welliver: Modified cement and concrete compositions. Air Products and Chemicals, William F Marsh, December 1, 1998: US05843222 (4 worldwide citation)

A cementitious composition comprising 0.1 to about 7.5 percent by weight of a solid residual oxidation product from the combustion of an aqueous emulsion of a naturally occurring asphalt from the Orinoco Belt of Venezuela which contains from about 100 to about 1500 ppm by weight of magnesium in the ...

Roth Timothy Jay, Welliver William Russell, Miller F Macgregor: Modified cement and concrete compositions. Air Prod & Chem, August 20, 1997: EP0790221-A1

Magnesium sulfate is admixed or interground with hydraulic silicate cement material to improve the properties of cement or concrete derived therefrom. Suitably, the magnesium sulfate is present in the oxidation product obtained by combustion of an asphalt.