Purification of ultralow sulfur diesel fuel
The invention is a method of purifying an ultralow sulfur diesel fuel which contains polycyclic aromatic color bodies. The method comprises contacting the ULSD fuel in the liquid phase with a coal-based activated carbon adsorbent having a surface area ranging from 800 to 1500 m 2 /g and containing pores having pore size greater than 20 Å, and recovering a purified diesel product having a decreased color bodies content.
1 . A method of purifying an ultralow sulfur diesel fuel containing polycyclic aromatic color bodies, which comprises contacting the ultralow sulfur diesel fuel in the liquid phase with a coal-based activated carbon adsorbent having a surface area ranging from 800 to 1500 m 2 /g and containing pores having pore size greater than 20 Å, and recovering a purified diesel product having a decreased polycyclic aromatic color bodies content.
2 . The method of claim 1 wherein the ultralow sulfur diesel fuel has a color greater than 2.5 as measured by ASTM D 6045.
3 . The method of claim 1 wherein the purified diesel product has a color less than 2.5 as measured by ASTM D 6045.
4 . The method of claim 1 wherein the carbon adsorbent has a surface area ranging from 800 to 1200 m 2 /g.
5 . The method of claim 1 wherein at least 10 percent of the total pore volume of the carbon adsorbent is in pores having a pore size greater than 20 Å.
6 . The method of claim 1 wherein at least 30 percent of the total pore volume of the carbon adsorbent is in pores having a pore size greater than 20 Å.
7 . The method of claim 1 wherein the carbon adsorbent is a granulated activated carbon.
8 . The method of claim 1 wherein the contacting is performed at a temperature within the range of about 10° C. to 60° C.
9 . A process for producing an ultralow sulfur diesel fuel, comprising:
(a) hydrodesulfurizing a diesel fuel stream in the presence of the supported hydrodesulfurization catalyst to produce an ultralow sulfur diesel fuel having a color greater than 2.5 as measured by ASTM D 6045;
(b) contacting the ultralow sulfur diesel fuel having a color greater than 2.5 in the liquid phase with a coal-based activated carbon adsorbent having a surface area ranging from 800 to 1500 m 2 /g and containing pores having pore size greater than 20 Å; and
(c) recovering an ultralow sulfur diesel product having a color less than 2.5 as measured by ASTM D 6045.
10 . The method of claim 9 wherein the carbon adsorbent has a surface area ranging from 800 to 1200 m 2 /g.
11 . The method of claim 9 wherein at least 10 percent of the total pore volume of the carbon adsorbent is in pores having a pore size greater than 20 Å.
12 . The method of claim 9 wherein at least 30 percent of the total pore volume of the carbon adsorbent is in pores having a pore size greater than 20 Å.
13 . The method of claim 9 wherein the carbon adsorbent is a granulated activated carbon.
14 . The method of claim 9 wherein the contacting is performed at a temperature within the range of about 10° C. to 60° C.