Unlock instant, AI-driven research and patent intelligence for your innovation.

Process for preparation and use of alcohols from a Fischer Tropsch process

a technology of fischer tropsch and process, which is applied in the direction of liquid carbonaceous fuels, organic chemistry, fuels, etc., can solve the problems of poor engine performance, increased pollution, early replacement of engine parts, etc., and achieves low olefin content, good lubricity, and increased yield

Inactive Publication Date: 2008-10-16
CHEVROU USA INC
View PDF16 Cites 1 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Benefits of technology

This method significantly improves the lubricity of distillate fuel blends by increasing the ASTM D6078 value by at least 225 grams and reducing the olefin-to-alcohol molar ratio to below 0.5, resulting in a clean, environmentally benign fuel with enhanced thermal stability and reduced refining needs.

Problems solved by technology

However, lubricity is required for the efficient operation of fuel delivery systems, and the need exists for an environmentally benign way of increasing the lubricity of clean distillate fuel blends.
Low lubricity can lead to excessive wear of metal engine parts which can result in poor engine performance, additional pollution, lower fuel mileage and early replacement of engine parts.
However, the amount of alcohols normally produced during a Fischer-Tropsch synthesis is not enough to raise the lubricity of the isoparaffinic distillate fuel blends to an acceptable level.
These naphthas are too volatile for incorporation into distillate transportation fuels and their levels of olefins and oxygenates makes them unsuitable for use in gasoline or as a petrochemical plant feed.
They are considered less valuable than distillate fuels but it is not possible to vary reaction conditions to selectively eliminate production of light naphthas and increase production of distillate transportation fuels.
The presence of olefins is undesirable and can lead to thermal stability problems, and also to the formation of gums.
In addition, a need exists for methods of recovering alcohols from a distillate fuel product and methods of removing unwanted olefins without the use of hydrogen, which is expensive.
However, these processes focus on the production of lower alkyl ethers that are more volatile than their starting alcohols or olefins, so the ethers could not be easily separated from the mixture by distillation.
Also, these processes do not address lubricity concerns or olefin content.
Often, the ethers and alcohols formed by known processes are of relatively low molecular weight, and sometimes environmentally harmful.
MTBE and TAME contaminate underground aquifers when gasoline spills or leaks.
Because these alcohols and their parent ethers lack protons on the carbon in the non-methyl group adjacent to the oxygen in the ether, they are not very biodegradable.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Examples

Experimental program
Comparison scheme
Effect test

example 1

Identification of Catalysts for Ether Synthesis from Alcohols

[0044]The following batch experiment was used to identify preferred catalysts for conversion of alcohols into ethers. For each trial, 1.0 g of catalyst was charged to a 25 mL stainless steel pressure batch reactor equipped with a magnetic stirring bar. The reactor was evacuated and backfilled with nitrogen several times. The initial pressure in the reactor was set at 560 psig by adding nitrogen gas. While under nitrogen, 5 mL of 1-butanol was added. The reactor was then heated with stirring for 18 hours at 200° C. Upon heating, the pressure rose to approximately 200-250 psig. At the end of the heating period, the reactor was cooled to room temperature and then to dry ice temperature. Through a rubber septum 5 mL of n-hexane was added. Next, ˜2 g of n-heptane was accurately weighed in to serve as an internal standard. The product was then removed from the reactor and analyzed by gas chromatography.

[0045]Samples of various a...

experiment 2

Olefin Hydration

[0047]The flow-type microunits used in this study were equipped with a stainless steel fixed bed reactor and an on-line GC. The catalysts studied for 1-butene hydration are as follows: Alumina base from Condea Chemie, calcined in air at 950° F. for 4 hours, Zeolite Y (CBV 901, no binder), Zeolite Al-SSZ-33, Zeolite Al-SSZ-42, Amberlyst Resin XN-1010, and Amberlyst Resin 15

[0048]The zeolite catalysts (0.24-0.26 g=4.0 cc each) were crushed to 24-60 mesh and, prior to the reaction, dehydrated in a N2 flow (200 cc / min) at 662° F. (350° C.) overnight.

[0049]The products were analyzed with an on-line GC using a HP-1 capillary column and a Flame Ionization Detector (FID). The FID Response Factors (RF) for 1-butanol, di-n-butyl ether and hydrocarbons were determined by assuming hydrocarbon RF=1.

ComponentResponse Factor (RF)1-butanol1.4663di-n-butyl ether1.2626octane (as internal standard)1.0000

[0050]The response factors are defined so that:

Wi=Woctane×(Ai / Aoctane)×(RFi / RFoctan...

experiment 3

Ether Hydrolysis

[0054]The following simple batch experiment can be used to identify catalysts useful for conversion of ethers into alcohols or olefins. Di-n-hexylether from Aldrich was used as a feedstock. Tests were performed at 200° C. using equipment and procedures described above.

[0055]Samples of various acidic catalysts were evaluated at 200° C. in this batch test with the following results. Catalysts were pelletized, crushed, and sized to 20 / 40 mesh. They were then calcined at 1100° F. in air. Catalyst samples (1 g) were charged to 25 mL metal batch reactors. The reactors were purged for 15 minutes with nitrogen gas at ambient pressure. Hexyl ether (5 g) and DI water (1 g) were added and the reactors sealed. The reactors were heated with stirring at 400 F for 24 hours. After cooling to ambient temperature, the reactors and contents were cooled to dry ice temperature and opened. Heptane was added as a solvent and n-octane added as an internal standard for GC analysis. Products ...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

PropertyMeasurementUnit
molar ratioaaaaaaaaaa
molar ratioaaaaaaaaaa
solubleaaaaaaaaaa
Login to View More

Abstract

Olefins and alcohols present in Fischer-Tropsch products are converted to primary and secondary alkyl alcohols having at least four carbons through acid catalyzed etherification and hydrolysis reactions. The alcohols are added to a highly isoparaffinic distillate fuel blend, improving the lubricity of the mixture, and forming a distillate fuel with improved lubricity.

Description

[0001]This invention relates generally to a distillate fuel having improved lubricity and to a method to prepare alcohols from a Fischer-Tropsch product. More specifically, this invention relates to a method to produce primary and secondary alkyl alcohols having at least four carbons by conversion of the alcohols and olefins in a Fischer-Tropsch product through acid catalyzed etherification and hydrolysis reactions. When these alcohols are added to a highly isoparaffinic distillate fuel blend, the lubricity of the mixture is improved.BACKGROUND OF THE INVENTION[0002]Because of the need to reduce fuel emissions, clean-burning middle distillate fuel blends such as diesel and jet fuels are required. These distillate fuel blends can come from many sources, including Fischer-Tropsch synthesis, olefin oligomerization, hydrotreating and hydrocracking processes and combinations thereof. One existing method of creating cleaner fuels involves the severe hydroisomerization of distillate stream...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Applications(United States)
IPC IPC(8): C10L1/18C07C29/10C10L1/02C10L1/182
CPCC07C29/10C10L1/026C10L1/1824C10L10/08C07C31/12C07C31/125
Inventor O'REAR, DENNIS J.HARRIS, THOMAS VANCHEN, CONG-YAN
Owner CHEVROU USA INC