Dismiss
InnovationQ will be updated on Sunday, Oct. 22, from 10am ET - noon. You may experience brief service interruptions during that time.
Browse Prior Art Database

Fischer-Tropsch Waxes - Production, Properties and Applications

IP.com Disclosure Number: IPCOM000126507D
Publication Date: 2005-Jul-22
Document File: 15 page(s) / 1M

Publishing Venue

The IP.com Prior Art Database

Related People

Madelein vd Merwe (Kleyn): ATTORNEY [+6]

Related Documents

IPCOM000021747D: IP.COM

Abstract

Fischer-Tropsch technology for the production of wax and middle distillate products is well documented. Decades of know-how regarding this subject matter have been documented in a recent publication "Fischer-Tropsch Technology", edited by A.P. Steynberg and M.E. Dry. As a result of changed and changing requirements in base oils products a variety of new and alternative production processes have been developed. The overall processes, whereby synthesis gas, derived from coal, gas or biomass are converted to wax and further hydrotreated to produce middle distillate products and lubricant base oils are known as the coal to liquids (CTL)–, gas to liquids (GTL)–, or biomass to liquids (BTL) processes. Synthetic paraffin waxes produced by the FT-process have become as significant as conventional wax products and its applications. Although FT-waxes have many identical properties to other paraffin waxes their structure, amongst other things, differs and the patent literature entertains the unique features of FT derived waxes and its many applications in numerous granted patents. Pure FT-wax, or FT-wax blends are now used widely in paraffin wax applications, and in various paraffin wax applications extensive R&D efforts have shown that FT-wax has the potential to replace natural or crude derived waxes.

This text was extracted from a Microsoft Word document.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 7% of the total text.

Fischer-Tropsch Waxes - Production, Properties and Applications

1 Introduction

Fischer-Tropsch (FT) technology for the production of wax and middle distillate products is well documented. Decades of know-how regarding this subject matter have been documented in a recent publication “Fischer-Tropsch Technology”, edited by A.P. Steynberg and M.E. Dry [ST04].

As a result of changed and changing requirements in base oils products a variety of new and alternative production processes have been developed. The overall processes, whereby synthesis gas, derived from coal, gas or biomass are converted to wax and further hydrotreated to produce middle distillate products and lubricant base oils are known as the coal to liquids (CTL)–, gas to liquids (GTL)–, or biomass to liquids (BTL) processes.

In addition to the existing plants in

South Africa

(Sasol) and

Malaysia

(Shell) new plants with the potential to produce FT-waxes will be up and running in the near future.

Synthetic paraffin waxes produced by the FT-process have become as significant as conventional wax products and its applications.

Although FT-waxes have many identical properties to other paraffin waxes their structure, amongst other things, differs and the patent literature entertains the unique features of FT derived waxes and its many applications in numerous granted patents. Pure FT-wax, or FT-wax blends are now used widely in paraffin wax applications, and in various paraffin wax applications extensive R&D efforts have shown that FT-wax has the potential to replace natural or crude derived waxes.

2. Production of FT-Waxes

The FT-process was developed in 1925 by F. Fischer and H. Tropsch. The main feedstock for the gasification process to synthesis gas and the subsequent polymerisation of the produced carbon monoxide to hydrocarbons is coal. Natural gas or biomass may also be used as feed material to produce synthesis gas. This is the reason for the renaissance of FT-process especially in offside remote regions without economic transportation or consumption possibilities.

In the (exothermic) FT-process one mole of CO reacts with two moles of H2 to yield a hydrocarbon chain extension (-CH2-). The oxygen from the CO is released as product water:

CO + 2H  →  -CH2 - + H2O

          ΔH = -165 kJ/mol

The reaction implies a H2/CO ratio of at least 2 for the synthesis of the hydrocarbons. When the ratio is lower it can be adjusted in the reactor with the catalytic Water-Gas Shift (WGS) reaction:

CO + H2O   →  CO2 + H2

          ΔH = -42 kJ/mol

When catalysts are used with WGS activity the water produced in the reaction can react with CO to form additional H2. In this case a minimal H2/CO ratio of 0.5 is required and the oxygen from the CO is released as CO2:

2CO + H2   →  - CH2 - + CO2

          ΔH = -204 kJ/mol

The ability to remove sulphur contents by conventional desulphurizing processes in the gas phase prevents poisoning of the FT-catalyst and ensures that final products are sulphur free.

The reaction yields ma...