March 16, 2015
Gasoline, diesel fuel, and base oils can be coproduced from biobased sources. The production of diesel fuel replacements from biobased sources is a well-known commercial technology, but processes for making biobased “drop-in” gasolines are still under development. The coproduction of both from renewable resources is the novelty of this patent.
Ethanol, which is used as a gasoline additive, allows partial substitution of biobased material; but for large-volume substitution, a drop-in solution is needed. Several concepts are at or near commercialization for gasoline or diesel, but few methods can produce a range of products, and none coproduce gasoline and diesel blending stocks.
M. Kettunen and co-inventors are investigating ways to produce gasoline, diesel, and base oils simultaneously from biobased sources. Their route is substantially different from other attempts to produce renewable gasoline in that the feedstock is lipids (triglycerides and/or free fatty acids). This is similar to other routes to renewable diesel, but the additional production of gasoline is of particular interest.
Even with the low levels of gasoline production in the examples, this is a significant development. The triglycerides and/or free fatty acids first undergo a ketonization reaction to produce a mixture of base-oil–range ketones. The ketones are then hydrodeoxygenated and isomerized to produce base oil and fuel-range alkanes.
In example 1 in the patent application, 100% palm oil was subjected to the process with a sulfidized 1:1 w/w K2O/TiO2-NiMo dual catalyst system at 365 ºC, 4 MPa, and a H2/feedstock ratio of 500:1. In example 5, liquid products from the hydrodeoxygenation step were isomerized in the presence of a noble metal bifunctional catalyst at a temperature of 311 ºC, a pressure of 5 MPa, and a H2/feedstock ratio of 800:1. The product distributions for both examples are shown in the table.
|Example||Gas (C1–C4) +
(Neste Oil Oyj [Espoo, Finland]. US Pat. Appl. 20150018581, Jan. 15, 2015; Steven R. Slome)