We claim:
1. A method for preparing a silica embedded carbon black composite
aggregate comprising:
a) feeding an oxidative gas, silica precursor and carbon black feedstock to a mixing chamber of a reactor assembly;
b) mixing the oxidative gas, silica precursor and carbon black feedstock in the mixing chamber to obtain a pre-mixed blended feedstock;
c) injecting the pre-mixed blended feedstock into a flame burner of the reactor assembly, said flame burner being operably connected to the mixing chamber;
d) generating heat of combustion through partial oxidative burning of the pre-mixed blended feedstock to attain reactor thermal conditions; and
e) cracking the pre-mixed blended feedstock to produce in-situ formed silica embedded carbon black composite aggregate.

2. The method as claimed in claim 1, wherein the oxidative gas is selected from air, nitrogen-oxygen mixtures, pure oxygen and mixture thereof.
3. The method as claimed in claim 1 or 2, wherein the carbon black feedstock comprises a fuel having high content of hydrocarbon.
4. The method as claimed in claim 3, wherein the fuel having high content of hydrocarbon is selected from various sources such as petroleum or its derivatives, heavy hydrocarbon oils, recovered pyrolysis oils and mixtures thereof.
5. The method as claimed in any one of claims 1 to 4, wherein the silica precursors are selected from organosilanes and organosilicates.
6. The method as claimed in claim 1, wherein weight ratio of the silica-precursor to the carbon black feedstock in the step a) is from 0.017 to 0.259.
7. The method as claimed in claim 1, further comprising collecting the silica embedded carbon black composite aggregate in a collector assembly.

8. The method as claimed in claim 7, further comprising filtering the silica embedded carbon black composite aggregate, said filtering being carried out by the collector assembly.
9. The method as claimed in claim 1, further comprising supplying an inert gas around the flame burner of the reactor assembly.
10. The silica embedded carbon black composite aggregate prepared by the method as claimed in any one of the preceding claims, wherein weight percent of the embedded silica particle in the composite aggregate is in a range of from about 30 % to about 60 %.
11. The silica embedded carbon black composite aggregate as claimed in claim 10, wherein a BET surface area of the silica embedded carbon black composite aggregate is in a range of from about 20 m2/g to about 180 m2/g.
12. The silica embedded carbon black composite aggregate as claimed in claim 10 or 11 whenever incorporated into a rubber composition.
13. A rubber composition comprising: (i) 100 phr of a rubber component; and
(ii) a silica embedded carbon black composite aggregate as claimed in claim 10 or 11, said composite aggregate being present in an amount of from 40 to 70 phr with respect to 100 phr of the rubber component.
14. A tyre comprising the rubber composition as claimed in claim 13.