Process for preparing a chlorine comprising catalyst, the prepared catalyst, and its use

Abstract

The invention concerns a process for preparing a chlorine comprising catalyst using one or more metal salts of chloride, hydrochloric acid (HCl), one or more organic chloride compounds, or a combination thereof. The prepared catalyst preferably comprises 0.13-3 weight percent of the element chlorine. The invention further relates to the prepared catalyst and its use.

Claims

1. A process for the preparation of a Fischer Tropsch catalyst, consisting of the steps of: (a) contacting cobalt and/or a cobalt compound; at least one promoter; one or more metal salts of chloride, hydrochloric acid (HCl), one or more organic chloride compounds, or a combination thereof; and a liquid; optionally one or more co-catalyst(s) or precursor(s) therefor; with titania; (b) drying the material obtained in step (a) at a temperature in the range of 70 to 350 C., whereby the material obtained in step (b) comprises: at least 5 weight percent cobalt, calculated on the total weight of the catalyst, in the range of between to 0.1 to 15 weight percent promoter, calculated on the total weight of the catalyst, and 0.13-4 weight percent of the element chlorine, calculated on the total weight of the catalyst.

2. A process according to claim 1, wherein a material is obtained in step (a) comprising 0.13-6 weight percent of the element chlorine, calculated on the total weight of the material obtained in step (a).

3. A process according to claim 1, wherein the liquid used in step (a) is water, ammonia, alcohol, ketone, aldehyde, aromatic solvent, or a mixture thereof.

4. A process according to claim 1, wherein the metal salt(s) of chloride with which the catalyst is contacted in step (a) is/are a chloride of manganese, cobalt, vanadium, titanium, silver, gold, zinc, platinum, palladium, zirconium, ruthenium, rhenium, rhodium, chromium, nickel, iron, osmium, or iridium or mixtures thereof.

5. A process according to claim 1, wherein fixed bed catalyst particle(s) larger than 1 mm, or immobilised slurry catalyst particles larger than 1 mm, are prepared.

6. A catalyst prepared according to any one of claims 1 to 5, said catalyst comprising 0.15-2 weight percent of the element chlorine, calculated on the total weight of the catalyst.

7. A process according to claim 1, wherein the at least one promoter is selected from the group consisting of manganese, rhenium, Group 8-10 noble metals, and mixtures thereof.

8. A process according to claim 7, wherein the Fischer-Tropsch catalyst comprises in the range of between to 0.1 to 15 weight percent manganese, rhenium, Group 8-10 noble metals, or mixtures thereof, calculated on the total weight of the catalyst.

9. A process for the preparation of a Fischer Tropsch catalyst, consisting of the steps of: (a1) contacting cobalt and/or a cobalt compound; at least one promoter; one or more metal salts of chloride, hydrochloric acid (HCl), one or more organic chloride compounds, or a combination thereof; and a liquid; optionally one or more co-catalyst(s) or precursor(s) therefor; with titania, obtaining a mixture (a2) shaping or forming catalyst particles by means of spray drying, pelletizing, (wheel) pressing or extruding the mixture obtained in step (a1), or application of the material obtained in step (a1) on a metal support (like a metal wire or a metal flake) (b) drying the catalyst particle obtained in step (a2) at a temperature in the range of 70 to 350 C. to obtain the Fischer-Tropsch catalyst, whereby the Fischer-Tropsch catalyst obtained in step (b) comprises: at least 5 weight percent cobalt, calculated on the total weight of the catalyst, in the range of between to 0.1 to 15 weight percent promoter, calculated on the total weight of the catalyst, and 0.13-4 weight percent of the element chlorine, calculated on the total weight of the catalyst.

10. A process according to claim 9, wherein the at least one promoter is selected from the group consisting of manganese, rhenium, Group 8-10 noble metals, and mixtures thereof.

Description

EXPERIMENTAL

(1) Measurement Method; Activity

(2) Catalytic activities can be measured, for example, in a model Fischer-Tropsch reactor. The catalytic activities measured may be expressed as space time yield (STY) or as an activity factor, whereby an activity factor of 1 corresponds to a space time yield (STY) of 100 g/l.Math.hr at 200 C.

(3) Sample Preparation

(4) Fixed bed particles were prepared as follows. Mixtures were prepared containing titania powder, cobalt hydroxide, manganese hydroxide, water and several extrusion aids. Depending on the experiment, no or a specific chlorine comprising compound was added to the mixture. The mixtures were kneaded. The mixtures were shaped using extrusion. The extrudates were dried and/or calcined. The obtained catalysts contained about 20 wt % cobalt and about 1 wt % of manganese.

(5) A part of the catalyst particles that was prepared without adding a chlorine comprising compound was used as reference (Comparative Examples). As one or more of the ingredients used comprised a very small amount of chlorine or chlorine components, the Comparative Examples comprised a very small amount of chlorine. Several batches were prepared, with slightly different properties.

(6) The comparative examples and the examples according to the invention were tested under different conditions. The experimental data can be compared per measurement set as presented below.

Examples 1-7

(7) Catalyst particles which were prepared as described above were prepared without adding a chlorine comprising compound in step (a), and were heated in step (b) at 300 C. This is referred to as Comparative Example 1.

(8) Catalyst particles which were prepared as described above were prepared with different amounts of cobalt chloride (CoCl.sub.2) in step (a), and then heated in step (b) at 300 C. The prepared catalysts comprised 0.1 to 1.4 weight percent of the element chlorine, calculated on the total weight of the catalyst. These catalysts are further referred to as Examples 1 to 3.

(9) Catalyst particles which were prepared as described above were prepared with hydrochloric acid (HCl) in step (a), and then heated in step (b) at 300 C. These catalysts are further referred to as Example 4.

(10) Catalyst particles which were prepared as described above were prepared without adding a chlorine comprising compound in step (a). Instead, cobalt nitrate (Co(NO3)2) was added in an amount equivalent to 2.5 wt % Co, calculated on the weight of the prepared catalyst. This is referred to as Comparative Example 2.

(11) Catalyst particles which were prepared as described above were prepared without adding a chlorine comprising compound in step (a), and were heated in step (b) at 595 C. This is referred to as Comparative Example 3.

(12) Catalyst particles which were prepared as described above were prepared with different amounts of cobalt chloride (CoCl.sub.2) in step (a), and then heated in step (b) at 595 C. These catalysts are further referred to as Examples 5 and 6.

(13) After the drying the chlorine content was determined.

(14) The catalyst particles were reduced with hydrogen.

(15) The performance of each of the different samples prepared was tested using the following conditions in a Fischer-Tropsch reactor: a H2/CO ratio of 1.1, 25% N2, 60 bar, and 215 C. The selectivity of each of the samples was determined at 30% CO conversion after 70-90 hours time on stream. The test results are summarized in Table 1.

(16) TABLE-US-00001 TABLE 1 Cl content Heating Cl after C5+ Cl comp. temp added drying select. Sample used ( C.) (wt %) (wt %) (%) Comp. Ex1 300 0 0.11 88.5 A1 CoCl2 300 0.15 0.20 90.7 A2 CoCl2 300 0.75 0.45 92.3 A3 CoCl2 300 3 1.42 92.3 A4 HCl 300 0.18 0.21 91.0 Comp. Ex2, 300 0 0.11 87.7 Co(NO3)2 Comp. Ex3 595 0 0.075 86.6 A6 CoCl2 595 0.15 0.096 87.5 A7 CoCl2 595 0.75 0.112 87.6

(17) From these experiments is clear that an increased amount of chlorine results in a higher selectivity towards C5+ hydrocarbons. This effect is thus seen for impregnation with metal chloride salts as well as for impregnation with HCl.

(18) From these experiments is clear that an increased amount of chlorine results in a higher selectivity towards C5+ hydrocarbons.

(19) The effects measured for the carbon C5+ selectivity is clearly due to the chloride which is impregnated, not to the cobalt. A very small amount of cobalt added to the 20 wt % cobalt comprising catalyst does not have a significant effect.