Methods of making ball milled and sonicated oil fly ash powder and uses thereof

2:

• The method of claim 1, wherein the ball milled and sonicated oil fly ash powder is contacted with the water for 5-60 min.

3:

• The method of claim 1, wherein the ball milled and sonicated oil fly ash powder has a carbon content of greater than 65 wt. %, based on a total weight of the ball milled and sonicated oil fly ash powder.

4:

• The method of claim 1, wherein the ball milled and sonicated oil fly ash powder has a SiO2 content of less than 3 wt. %, and a Al2O3 content of less than 3 wt. %, each based on a total weight of the ball milled and sonicated oil fly ash powder.

5:

• The method of claim 1, wherein the ball milled and sonicated oil fly ash powder has a bimodal particle size distribution with nanoparticles having an average particle size of 10-100 nm, and sub-micron sized particles having an average particle size of 0.2-0.9 μm.

6:

• The method of claim 1, wherein 0.01-0.5 g of the ball milled and sonicated oil fly ash powder is employed per L of the water during the contacting.

7:

• The method of claim 1, wherein the organic pollutant is at least one selected from the group consisting of methylene blue, Congo red, brilliant green, and crystal violet.

8:

• The method of claim 1, wherein at least 75% of the organic pollutant is removed from the water relative to an initial concentration.

10:

• The method of claim 9, wherein the oil fly ash has a carbon content of greater than 65 wt. %, based on a total weight of the oil fly ash.

11:

• The method of claim 9, wherein the oil fly ash has a SiO2 content of less than 3 wt. %, and a Al2O3 content of less than 3 wt. %, each based on a total weight of the oil fly ash.

12:

• The method of claim 9, wherein the oil fly ash has a vanadium content of 1,000-70,000 ppm, and a nickel content of 500-15,000 ppm.

13:

• The method of claim 9, wherein the ball milled and sonicated oil fly ash powder has an average particle size of less than less than 1 μm.

14:

• The method of claim 13, wherein the ball milled and sonicated oil fly ash powder has a bimodal particle size distribution with nanoparticles having an average particle size of 10-100 nm, and sub-micron sized particles having an average particle size of 0.2-0.9 μm.

15:

• The method of claim 9, wherein the oil fly ash is ball milled in a high energy ball mill at a rotational speed of 100 to 400 rpm.

16:

• The method of claim 9, wherein the oil fly ash is ball milled in tungsten carbide vials with tungsten carbide or stainless steel balls, and with a ball to oil fly ash weight ratio of from 8:1 to 12:1.

17:

• The method of claim 9, wherein the oil fly ash particles are ball milled for 5-11 hours and sonicated for at least 1 hour.

18:

• The method of claim 9, further comprising shaking and/or stirring the mixture for at least 30 min. after sonicating.

20:

• The method of claim 19, wherein the oil fly ash has a vanadium content of 1,000-70,000 ppm and a nickel content of 500-15,000 ppm, and the method provides 20-50% more vanadium and 40-80% more nickel compared to a process employing oil fly ash which is shaken and/or stirred in the aqueous medium but has not been ball milled or sonicated.