Catalyst for direct production of isoparaffins-rich synthetic oil and a method for preparing the catalyst

Abstract

A catalyst for producing isoparaffins-rich synthetic oil is a granulated porous composite material comprising a three-dimensional heat-conducting structure of metal aluminum and Raney cobalt, and a binding component comprising an H-form zeolite. The particles of Raney cobalt and zeolite are in mutual direct contact. Fractions of macropores in an open porosity of the catalyst granules and of mesopores of the size of 70-500 in an open porosity of the catalyst granules are respectively 55-79% and 7-20%, a fraction of micropores being the rest. A method for preparing the catalyst comprises mixing binding component powders, peptizing the mixture with a nitric acid solution, mixing obtained homogeneous gel with powders of Raney cobalt and metal aluminum and a liquid phase to form a paste, extruding same into granules and calcinating the granules. The catalyst improves reagents mass transfer inside the granules and increases isoparaffine content in the produced oil.

Claims

1. A catalyst for producing isoparaffins-rich synthetic oil from CO and H.sub.2, wherein said catalyst is a granulated porous composite material comprising: a three-dimensional heat-conducting structure of metal aluminum and Raney cobalt particles, and a binding component, wherein said binding component comprises H-form zeolite and wherein a fraction of macropores in an open porosity of the catalyst granules is 55-79% and a fraction of mesopores of the size of 70-500 in an open porosity of the catalyst granules is 7-20%, a fraction of micropores being the remainder.

2. The catalyst of claim 1, wherein the thermal conductivity of the catalyst granules is no less than 4 W/m.Math.K.

3. The catalyst of claim 1, wherein said H-form zeolite comprises beta zeolite, mordenite, ZSM-5, or any combination thereof.

4. The catalyst of claim 1, wherein the content of said Raney cobalt is 10-50% of the catalyst weight.

5. The catalyst of claim 1, wherein the content of said metal aluminum is 10-50% of the catalyst weight.

6. The catalyst of claim 1, wherein the content of said binding component is 15-80% of the catalyst weight.

7. The catalyst of claim 1, wherein said binding component further comprises boehmite.

8. The catalyst of claim 7, wherein the content of said H-form zeolite is 20-70% of the weight of said binding component.

9. A method for preparing a catalyst of any of claims 2-8 for producing isoparaffins-rich synthetic oil from CO and H.sub.2, the method comprising: mixing powders of a binding component, peptizing the obtained mixture with solution of nitric acid to obtain said binding component in the form of a homogeneous gel, mixing said homogeneous gel with a fine powder of Raney cobalt, a metal aluminum powder and a liquid phase to form a homogeneous paste, extruding the prepared paste to form granules and calcinating said granules, wherein said binding component powders comprise zeolite in H-form.

10. The method of claim 9, wherein said binding component powders further comprise boehmite.

11. The method of claim 9, wherein said liquid phase includes triethylene glycol and/or ethyl alcohol.

12. The method of claim 9, wherein said calcinating said granules is performed in air or inert atmosphere at the temperature increasing from 25 C. to 450 C. for 24-48 hours.

13. The method of claim 12, wherein said calcinating said granules is performed in air or inert atmosphere for 20-30 hours.

14. The method of claim 9, wherein the finished catalyst granules have thermal conductivity of no less than 4 W/m.Math.K.

Description

DETAILED DESCRIPTION OF THE INVENTION

(1) The method for preparing the catalyst according to the present invention is carried out as follows. The boehmite powder and the H-form zeolite powder are mixed. The latter may be beta zeolite in H-form and/or mordenite in H-form and/or ZSM-5 in H-form. The mixture of these powders is peptized with a solution of nitric acid to form a homogeneous gel. Then, this gel is mixed with the finely-divided Raney cobalt, finely-divided metal aluminum, triethylene glycol and ethyl alcohol to form a homogeneous paste. The prepared paste is extruded to form granules, which then are calcined. As a result, the catalyst according to the present invention is prepared, being a granulated porous composite material comprising a three-dimensional heat-conducting structure of metal aluminum and Raney cobalt as well as a binding component comprising zeolite in H-form, with the Raney cobalt particles being in direct contact with the zeolite particles.

(2) The finished granules of the catalyst according to the present invention have thermal conductivity no less than 4 W/m.Math.K and characterized by the presence of macropores, the fraction of which in open porosity of the catalyst is 55-79%, and mesopores of the size of 70-500 , the fraction of which in open porosity of the granules is 7-20%, a fraction of micropores being the rest.

(3) Before the synthesis of oil from CO and H.sub.2, the catalyst is activated in a hydrogen stream or a hydrogen-containing gas stream (volume velocity is 1000-10000 h.sup.1, preferably 3000-5000 h.sup.1) at the atmospheric pressure and the temperature of 300-450 C. for 0.5-10 hours (preferably 1-5 hours).

(4) The synthesis of the oil is carried out in a tubular reactor with a fixed bed of the catalyst at the pressure of 1-5 MPa, preferably 2-2.5 MPa, and the temperature of 160-320 C., preferably 180-250 C. The CO:H.sub.2 molar ratio in the syngas is 1:13 (preferably 1:22.5). The syngas may comprise up to 20% of nitrogen.

INDUSTRIAL APPLICABILITY

EXAMPLE 1

(5) A catalyst comprising 10% of HB (beta zeolite in H-form), 20% of Raney cobalt, 50% of Al and 20% of boehmite was prepared as follows.

(6) Powders of HB zeolite (1 g) and boehmite (2 g) were thoroughly mixed in a porcelain dish, the obtained mixture was peptized with a solution of 0.45 ml of HNO.sub.3 (64%) in 7 ml of distilled water and mixed to form a homogeneous gel. Raney cobalt in the amount of 2 g, 5 g of PAP-2 aluminum powder, 1.5 g of triethylene glycol grade A, and 3 g of ethyl alcohol were added to the prepared gel. The content of the dish was thoroughly mixed to form a homogeneous paste. The prepared paste was introduced into an extruder, the die diameter of which was 2.5 mm, and extruded. The obtained granules were held in air at the room temperature for 15 hours and calcined in an air stream at the temperature increasing from 25 to 450 C. for 27 hours. The prepared granules were cooled to the room temperature and crushed to the particle size of 2.52.5 mm.

(7) Thermal conductivity of the finished catalyst was 4.57 W/m.Math.K, the fraction of macropores in open porosity of the catalyst was 69.7%, and the fraction of mesopores of the size of 70-500 was 17.8%.

(8) Before the synthesis of the oil, the catalyst was activated in a hydrogen stream (3000 h.sup.1) at the atmospheric pressure and the temperature of 400 C. for 1 hour.

(9) As a result of the synthesis from CO and H.sub.2 at the temperature of 233 C. and the syngas velocity of 1000 h.sup.1, hydrocarbons C.sub.5+ were produced, the isoparaffins content being 30% in the synthetic oil and 40% by weight in the diesel fraction, the productivity for isoparaffins was 44 g/kgcat/h, the cloud point temperature of the synthetic oil was minus 78 C. When the synthesis was carried out at the temperature of 248 C. and the syngas velocity of 5000 h.sup.1, the isoparaffins content was 30% by weight, the productivity for isoparaffins was 61 g/kgcat/h and the cloud point temperature was minus 82 C.

EXAMPLE 2

(10) A catalyst comprising 15% of HB, 15% of Raney cobalt, 50% of Al and 20% of boehmite was prepared as follows.

(11) Powders of HB zeolite (1.5 g) and boehmite (2 g) were thoroughly mixed in a porcelain dish, the obtained mixture was peptized with a solution of 0.45 ml of HNO.sub.3 (64%) in 7 ml of distilled water and mixed to form a homogeneous gel. Raney cobalt in the amount of 1.5 g, 5 g of PAP-2 aluminum powder, 1.5 g of triethylene glycol grade A, and 3 g of ethyl alcohol were added to the prepared gel. The content of the dish was thoroughly mixed to form a homogeneous paste. The prepared paste was introduced into an extruder, the die diameter of which was 2.5 mm, and extruded. The obtained granules were held in air at the room temperature for 15 hours and calcined in an air stream at the temperature increasing from 25 to 450 C. for 27 hours. The prepared granules were cooled to the room temperature and crushed to the particle size of 2.52.5 mm.

(12) Thermal conductivity of the prepared catalyst was 4.42 W/m.Math.K, the fraction of macropores in open porosity of the catalyst was 70.5%, and the fraction of mesopores of the size of 70-500 was 19.2%.

(13) Before the synthesis of oil, the catalyst was activated in a hydrogen stream (3000 h.sup.1) at the atmospheric pressure and temperature of 400 C. for 1 hour.

(14) As a result of the synthesis from CO and H.sub.2 at the temperature of 231 C. and the syngas velocity of 1000 h.sup.1, hydrocarbons C.sub.5+ were produced, the isoparaffins content was 30% in the synthetic oil and 40% by weight in the diesel fraction, the productivity for isoparaffins was 44 g/kgcat/h, the cloud point temperature of the synthetic oil was minus 78 C. When the synthesis was carried out at the temperature of 248 C. and the syngas velocity of 5000 h.sup.1, the isoparaffins content was 30% by weight, the productivity for isoparaffins was 61 g/kgcat/h and the cloud point temperature was minus 82 C.

EXAMPLE 3

(15) A catalyst comprising 20% of HB, 10% of Raney cobalt, 50% of Al and 20% of boehmite was prepared as follows.

(16) Powders of HB zeolite (2 g) and boehmite (2 g) were thoroughly mixed in a porcelain dish, the obtained mixture was peptized with a solution of 0.45 ml of HNO.sub.3 (64%) in 7 ml of distilled water and mixed to form a homogeneous gel. Raney cobalt in the amount of 1 g, 5 g of PAP-2 aluminum powder, 1.5 g of triethylene glycol grade A, and 3 g of ethyl alcohol were added to the prepared gel. The content of the dish was thoroughly mixed to form a homogeneous paste. The prepared paste was introduced into an extruder, the die diameter of which was 2.5 mm, and extruded. The obtained granules were held in air at the room temperature for 15 hours and calcined in an air stream at the temperature increasing from 25 to 450 C. for 27 hours. The prepared granules were cooled to the room temperature and crushed to the particle size of 2.52.5 mm.

(17) Thermal conductivity of the produced catalyst was 4.17 W/m.Math.K, the fraction of macropores in open porosity of catalyst was 73.4%, and the fraction of mesopores of the size of 70-500 was 17.1%.

(18) The catalyst was activated in a hydrogen stream (3000 h.sup.1) at the atmospheric pressure and temperature of 400 C. for 1 hour.

(19) As a result of the synthesis from CO and H.sub.2 at the temperature of 228 C. and the syngas velocity of 1000 h.sup.1, hydrocarbons C.sub.5+ were produced, the isoparaffins content was 28% in the synthetic oil and 38% by weight in the diesel fraction, the productivity for isoparaffins was 43 g/kgcat/h, the cloud point temperature of the synthetic oil was minus 66 C., and when the synthesis was carried out at the temperature of 243 C. and the syngas velocity of 4000 h.sup.1, the isoparaffins content was 26% by weight, the productivity for isoparaffins was 79 g/kgcat/h and the cloud point temperature was minus 70 C.

EXAMPLE 4

(20) A catalyst comprising 20% of HB, 50% of Raney cobalt, 10% of Al and 20% of boehmite was prepared as follows.

(21) Powders of HB zeolite (2 g) and boehmite (2 g) were thoroughly mixed in a porcelain dish, the obtained mixture was peptized with a solution of 0.45 ml of HNO.sub.3 (64%) in 7 ml of distilled water and mixed to form a homogeneous gel. Raney cobalt in the amount of 5 g, 1 g of PAP-2 aluminum powder, 1.5 g of triethylene glycol grade A, and 3 g of ethyl alcohol were added to the prepared gel. The content of the dish was thoroughly mixed to form a homogeneous paste. The prepared paste was introduced into an extruder, the die diameter of which was 2.5 mm, and extruded. The obtained granules were held in air at the room temperature for 15 hours and calcined in a nitrogen stream at the temperature increasing from 25 to 450 C. for 30 hours. The prepared granules were cooled to room temperature and crushed to the particle size of 2.52.5 mm.

(22) Thermal conductivity of the prepared catalyst was 4.11 W/m.Math.K, the fraction of macropores in open porosity of the catalyst was 78.4%, and the fraction of mesopores of the size of 70-500 was 16.8%.

(23) The catalyst was activated in a hydrogen stream (3000 h.sup.1) at the atmospheric pressure and temperature of 400 C. for 1 hour.

(24) As a result of the synthesis from CO and H.sub.2 at the temperature of 228 C. and the syngas velocity of 1000 h.sup.1, hydrocarbons C.sub.5+ were produced, the isoparaffins content was 26% in the synthetic oil and 39% by weight in the diesel fraction, the productivity for isoparaffins was 43 g/kgcat/h, the cloud point temperature of the synthetic oil was minus 69 C., and when the synthesis was carried out at the temperature of 246 C. and the syngas velocity of 5000 h.sup.1, the isoparaffins content was 29% by weight, the productivity for isoparaffins was 94 g/kgcat/h and the cloud point temperature was minus 74 C.

EXAMPLE 5

(25) A catalyst comprising 3% of HMor (mordenite in H-form), 27% of Raney cobalt, 50% of Al and 20% of boehmite was prepared as follows.

(26) Powders of HMor mordenite (0.3 g) and boehmite (2 g) was thoroughly mixed in a porcelain dish, the obtained mixture was peptized with a solution of 0.45 ml of HNO.sub.3 (64%) in 7 ml of distilled water and mixed to form a homogeneous gel. Raney cobalt in the amount of 2.7 g, 5 g of PAP-2 aluminum powder, 1.5 g of triethylene glycol grade A and 3 g of ethyl alcohol were added into the prepared gel. The content of the dish was thoroughly mixed to form a homogeneous paste. The prepared paste was introduced into an extruder, the die diameter of which was 2.5 mm, and extruded. The obtained granules were held in air at the room temperature for 15 hours and calcined in a helium stream at the temperature increasing from 25 to 450 C. for 25 hours. The prepared granules were cooled to the room temperature and crushed to the particle size of 2.52.5 mm.

(27) Thermal conductivity of the prepared catalyst was 4.22 W/m.Math.K, the fraction of macropores in open porosity of the catalyst was 67.1%, and the fraction of mesopores of the size of 70-500 was 15.2%.

(28) The catalyst was activated in a hydrogen stream (3000 h.sup.1) at the atmospheric pressure and temperature of 400 C. for 1 hour.

(29) As a result of the synthesis from CO and H.sub.2 at the temperature of 233 C. and the syngas velocity of 1000 h.sup.1, hydrocarbons C.sub.5+ were produced, the isoparaffins content was 25% in the synthetic oil and 35% by weight in the diesel fraction, the productivity for isoparaffins was 35 g/kg.sub.cat.Math.h, the cloud point temperature of the synthetic oil was minus 67 C., and when the synthesis was carried out at the temperature of 248 C. and the syngas velocity of 5000 h.sup.1, the isoparaffins content was 29% by weight, the productivity for isoparaffins was 73 g/kgcat/h and the cloud point temperature was minus 71 C.

EXAMPLE 6

(30) A catalyst comprising 40% of HZSM-5 (ZSM-5 in H-form), 20% of Raney cobalt, 40% of Al and 20% of boehmite was prepared as follows.

(31) Powders of HZSM-5 zeolite (4 g) and boehmite (2 g) were thoroughly mixed in a porcelain dish, the obtained mixture was peptized with a solution of 0.45 ml of HNO.sub.3 (64%) in 7 ml of distilled water and mixed to form a homogeneous gel. Raney cobalt in the amount of 2 g, 4 g of PAP-2 aluminum powder, 1.5 g of triethylene glycol grade A, and 3 g of ethyl alcohol were added to the prepared gel. The content of the dish was thoroughly mixed to form a homogeneous paste. The prepared paste was introduced into an extruder, the die diameter of which was 2.5 mm, and extruded. The obtained granules were held in air at the room temperature for 18 hours and calcined in an air stream at the temperature increasing from 25 to 450 C. for 25 hours. The prepared granules were cooled to the room temperature and crushed to the particle size of 2.52.5 mm.

(32) Thermal conductivity of the prepared catalyst was 4.12 W/m.Math.K, the fraction of macropores in open porosity of the catalyst was 68.3%, and the fraction of mesopores of the size of 70-500 was 14.8%.

(33) The catalyst was activated in a hydrogen stream (3000 h.sup.1) at the atmospheric pressure and temperature of 400 C. for 1 hour.

(34) As a result of the synthesis from CO and H.sub.2 at the temperature of 225 C. and the syngas velocity of 1000 h.sup.1, hydrocarbons C.sub.5+ were produced, the isoparaffins content was 19% in the synthetic oil and 39% by weight in the diesel fraction, the productivity for isoparaffins was 40 g/kg.sub.cat.Math.h, the cloud point temperature of the synthetic oil was minus 70 C., and when the synthesis was carried out at the temperature of 237 C. and syngas velocity of 5000 h.sup.1, the isoparaffins content was 35% by weight, the productivity for isoparaffins was 110 g/kg.sub.cat.Math.h and the cloud point temperature was minus 77 C.

EXAMPLE 7 (for Comparison, Without Using Zeolite in H-form)

(35) A catalyst comprising 25% of Raney Co, 50% of Al and 25% of boehmite was prepared as follows.

(36) Boehmite in the amount of 2.5 g, 2.5 g of Raney cobalt, 5 g of PAP-2 aluminum powder, and 1.5 g of triethylene glycol grade A were mixed in a porcelain dish and peptized with a solution of 0.45 ml of HNO.sub.3 (64%) in 10 ml of distilled water. The content of the dish was thoroughly mixed to form a homogeneous paste. The prepared paste was introduced into an extruder, the die diameter of which was 2.5 mm, and extruded. The obtained granules were held in air at the room temperature for 15 hours and calcined in an air stream at the temperature increasing from 25 to 450 C. for 27 hours. The prepared granules were cooled to the room temperature and crushed to the particle size of 2.52.5 mm.

(37) Thermal conductivity of the prepared catalyst was 3.56 W/m.Math.K, the fraction of macropores in open porosity of the catalyst was 80.1%, and the fraction of mesopores of the size of 70-500 was 24.1%.

(38) The catalyst was activated in a hydrogen stream (3000 h.sup.1) at the atmospheric pressure and temperature of 400 C. for 1 hour.

(39) As a result of the synthesis from CO and H.sub.2 at the temperature of 233 C. and the syngas velocity of 2000 h.sup.1, hydrocarbons C.sub.5+ were produced, the isoparaffins content was 13% in the synthetic oil and 8% by weight in the diesel fraction, the productivity for isoparaffins was 32 g/kgcat/h, the cloud point temperature of the synthetic oil was minus 15 C.