Clean diesel fuel and methods of producing clean diesel fuel

Abstract

A low emissions "clean" diesel fuel and methods of producing a clean diesel fuel are provided. In one aspect, this invention relates to a method of producing a diesel fuel which provides reduced, or at least substantially equivalent, emissions of oxides of nitrogen ("NO x ") In another aspect this invention relates to a clean diesel fuel composition which is economical to produce, meets regulatory specifications, and has desirable characteristics including acceptable aromatics content and cetane number.

I claim: 
     
       1. A diesel fuel, having reduced, or at least substantially equivalent, emissions of oxides of nitrogen as compared to a reference fuel containing 10% by volume aromatics prepared in accordance with Title 13, California Code of Regulations effective at Oct. 1, 1993, characterized by: a. a cetane number (per ASTM D-613-84) not less than 55.2; and,   b. total aromatics (per ASTM D-1319-84), not less than 21 percent by weight nor greater than 21.7 percent by weight.   
     
     
       2. A diesel fuel in accordance with claim 1 further characterized by: a. polycyclic aromatics (per ASTM D-2424-83) not greater than about 4.6 percent by weight;   b. sulfur content (per ASTM D-2622-82) not greater than about 33 parts per million by weight; and,   c. nitrogen content (per ASTM D-4629-86) not greater than about 20 parts per million by weight.   
     
     
       3. A diesel fuel, having reduced, or at least substantially equivalent, emissions of oxides of nitrogen as compared to a reference fuel containing 10% by volume aromatics prepared in accordance with Title 13, California Code of Regulations effective at Oct. 1, 1993, characterized by: a. a cetane number (per ASTM D-613-84) not less than 56.2; and,   b. total aromatics (per ASTM D-1319-84) not less than 21 percent by weight nor greater than 24.7 percent by weight.   
     
     
       4. A diesel fuel in accordance with claim 3 further chracterized by: a. polycyclic aromatics (per ASTM D-2424-83) not greater than about 4.0 percent by weight;   b. sulfur content (per ASTM D-2622-82) not greater than about 42 parts per million by weight; and,   c. nitrogen content (per ASTM D-4629-86) not greater than about 40 parts per million by weight.