Fuel oil compositions

A process for improving the regenerative ability of a particulate trap of a fuel oil composition device, which process consists of:

• supplying directly to the trap an additive composition;
• wherein the additive composition consists of:
• (a) at least one fuel-soluble or fuel-dispersible alkaline earth metal compound selected from the group consisting of calcium sulfonate and calcium salicylate, and
• (b) at least one fuel-soluble or fuel-dispersible transition metal compound including a transition metal selected from the group consisting of iron, copper, cerium, chromium, cobalt and molybdenum;
• and
• wherein the fuel oil composition contains at most 0.05 mass percent of sulfur, the total metal content of the alkaline earth metal compound and the transition metal compound in the fuel oil composition is at most 50 ppm by mass, the mass proportion of metal in the alkaline earth metal compound to metal in the transition metal compound is in the range of about 60:40 to about 95:5, the alkaline earth metal compound includes an organic anion and metal associated with the organic anion, the ratio of metal in the alkaline earth compound to metal associated with the organic anion is less than about 2, and the fuel composition does not comprise a manganese compound.

A process for improving the regenerative ability of a particulate trap of a fuel oil composition device, which process consists of:

• adding to the fuel oil combustion device a fuel oil composition incorporating an additive composition;
• wherein the additive composition consists of:
• (a) at least one fuel-soluble or fuel-dispersible alkaline earth metal compound selected from the group consisting of calcium sulfonate and calcium salicylate, and
• (b) at least one fuel-soluble or fuel-dispersible transition metal compound including a transition metal selected from the group consisting of iron, copper, cerium, chromium, cobalt and molybdenum;
• and
• wherein the fuel oil composition contains at most 0.05 mass percent of sulfur, the total metal content of the alkaline earth metal compound and the transition metal compound in the fuel oil composition is at most 50 ppm by mass, the mass proportion of metal in the alkaline earth metal compound to metal in the transition metal compound is in the range of about 60:40 to about 95:5, the alkaline earth metal compound includes an organic anion and metal associated with the organic anion, the ratio of metal in the alkaline earth compound to metal associated with the organic anion is less than about 2, and the fuel composition does not comprise a manganese compound.