WO2019014712A1

WO2019014712A1 - Dimethoxymethane production via direct hydrogenation

Info

Publication number: WO2019014712A1
Application number: PCT/AU2018/050746
Authority: WO
Inventors: Akshat Tanksale; Fan Liang Chan
Original assignee: Monash University
Priority date: 2017-07-17
Filing date: 2018-07-17
Publication date: 2019-01-24

Abstract

A process of producing oxymethylene ethers comprising the steps of: a) contacting hydrogen gas and CO and/or CO2 with a mixture of methanol and a catalyst at conditions of temperature and pressure to support hydrogenation of the CO and/or CO2 gas in the synthesis gas to oxymethylene ethers; the catalyst comprising: i. catalytic material being at least one metal selected from the group of Ni, Ru, Cu, Pt and Pd; and ii. an acidic catalyst support being at least one selected from the group of zeolites, alumina, amorphous silica-alumina and silica; and b) separating the oxymethylene ethers from the catalyst. Also disclosed herein is a catalyst for the production of dimethoxymethane from synthesis gas in a single contacting step comprising i. catalytic material comprising at least one metal selected from the group of Ni, Pt, Ru, Cu and Pd; and ii. an acidic catalyst support comprising at least one support selected from the group of zeolites, alumina, amorphous silica-alumina and silica.

Description

Dimethoxymethane production via direct hydrogenation

Field of the invention

The present invention relates to the production of dimethoxymethane and in particular to a method of producing dimethoxymethane in a single contact step process. Background of the invention

Oxymethylene Ethers (OMEs) are a class of second generation fuel components that can be blended with diesel in large volume fractions to reduce soot emission and to make transportation fuels more sustainable. OMEs can be produced from methanol and formaldehyde using an acid catalyst. The current industrial production method of OME (also known as Dimethoxy

Methane, DMM) is based on a two-step process whereby methanol is first partially oxidised into formaldehyde in gas phase in a first reactor, followed by liquid phase acetalization of the as-obtained formaldehyde with methanol in a second reactor. This process suffers from significant losses due to the long chain of reactions starting from natural gas to produce synthesis gas, followed by methanol synthesis and then partial oxidation of methanol into formaldehyde and then the final step of acetalization to produce OMEi .

The inventors have recently shown that the formaldehyde synthesis process of the prior art suffers from 57% exergy loss due to this long chain of processes, high temperature reactions, and large purification steps required. There would be further losses in the production of OMEi using this route. Recently there has been keen interest in developing alternative methods of OMEi production, including one-step selective partial oxidation of methanol to OME-i, however, there are no attempts as yet to produce OME directly from synthesis gas, thereby by-passing the methanol synthesis completely.

Reference to any prior art in the specification is not an acknowledgment or suggestion that this prior art forms part of the common general knowledge in any jurisdiction or that this prior art could reasonably be expected to be understood, regarded as relevant, and/or combined with other pieces of prior art by a skilled person in the art.

Summary of the invention

According to a first aspect of the invention, there is provided a process of producing dimethoxymethane comprising the steps of: a) contacting a synthesis gas of at least CO with a mixture of methanol and a catalyst at conditions of temperature and pressure to support hydrogenation of the CO in the synthesis gas to dimethoxymethane; the catalyst comprising i. catalytic material being at least one metal selected from the group of Ni, Ru, Cu, Pt and Pd; and ii. an acidic catalyst support being at least one selected from the group of zeolites, alumina, amorphous silica-alumina and silica b) separating the dimethoxymethane from the catalyst.

Preferably the catalyst support further includes an acidic ion exchange resin to increase the acidity of the catalyst support. The synthesis gas which contains at least CO and may also contain CO₂ is fed to a reactor with methanol and catalyst. The catalyst is a bifunctional catalyst which comprises a catalytic metal which catalyses the reaction of synthesis gas and hydrogen to formaldehyde and an acidic catalyst support which catalyses the acetalization of the formaldehyde to dimethoxymethane. The process of the invention is able to produce dimethoxymethane directly from synthesis gas and methanol in a single contacting step.

The methanol and catalyst is preferably in the form of slurry and the synthesis gas mixed with the slurry in the reactor under conditions which promote hydrogenation. The ratio of CO to hydrogen in the synthesis gas is preferably in the range of 1 :1 to 1 :20 but is more preferably about 1 :2. The conditions to support hydrogenation of the CO in the synthesis gas initially to dimethoxymethane is a temperature in the range of 0 - 200°C, preferably 50 - 150°C, and a pressure of 50-200bar

The catalyst is preferably formed by loading metal oxide catalyst onto an acidic catalyst support which may have been modified to have a size pore structure to which the metal oxide is loaded. A further catalyst support such as an ion exchange resin may also be added to increase the acidity of the catalyst. The metal oxide on the catalytic support is then reduced to activate the catalytic metal.

In a second aspect of the invention, there is provided a process of producing oxymethylene ethers comprising the steps of: a) contacting a hydrogen gas, CO and/or CO₂ with a mixture of methanol and a catalyst at conditions of temperature and pressure to support hydrogenation of the CO and/or CO₂ gas in the synthesis gas to oxymethylene ethers; the catalyst comprising: i. catalytic material being at least one metal selected from the group of Ni,

Ru, Cu, Pt and Pd; and ii. an acidic catalyst support being at least one selected from the group of zeolites, alumina, amorphous silica-alumina and silica b) separating the oxymethylene ethers from the catalyst. In an embodiment, the catalyst is a bifunctional catalyst that comprises a catalytic metal which catalyses the reaction of synthesis gas and hydrogen to formaldehyde and an acidic catalyst support which catalyses the acetalization of the formaldehyde to oxymethylene ethers.

In an embodiment, the catalyst support further includes an acidic ion exchange resin to increase the acidity of the catalyst support. Preferably, the acidic cation exchange resin is an acidic sulfonic acid cation exchange resin.

In an embodiment, the catalytic material is at least one metal selected from the group of Ni(0), Ru(0), Cu(0), Pt(0) and Pd(0).

In an embodiment, the catalytic material is at least two metals. In an embodiment, the ratio of CO and/or CO₂ to hydrogen in the synthesis gas is from 1 :1 to 1 :20. Most preferably, the ratio is from about 1 :2. In forms of the invention that include contacting the hydrogen gas with CO, it is preferred that the ratio of CO to hydrogen in the synthesis gas is from 1 :1 to 1 :20. More preferably, the ratio is from about 1 :2.

In forms of the invention that include contacting the hydrogen gas with CO₂, it is preferred that the ratio of CO₂ to hydrogen in the synthesis gas is from 1 :1 to 1 :20. More preferably, the ratio is from about 1 :2. Most preferably, the ratio is from about 1 :3.

In an embodiment, the contacting step is carried out at a temperature of from about 0°C up to about 200°C. Preferably, the temperature is from about 20°C. More preferably, the temperature is from about 40°C. Most preferably, the temperature is from about 50°C. Alternatively, or additionally, it is preferred that the temperature is up to 190°C. More preferably, the temperature is up to 180°C. Most preferably, the temperature is up to 170°C. By way of example, in one form of the invention, the temperature is from 50 up to 150°C.

In an embodiment, the contacting step is carried out at a pressure of from about 50 bar up to about 200 bar. Preferably, the pressure is from about 60 bar. More preferably, the pressure is from about 70 bar. Most preferably, the pressure is from about 75 bar. Alternatively, or additionally, the pressure is up to about 1 75 bar. More preferably, the pressure is up to about 150 bar. Most preferably, the pressure is up to about 125 bar. By way of example, in one form of the invention, the pressure is from 50 up to 200bar

In an embodiment, the ratio of partial pressure of hydrogen to partial pressure of CO and/or CO₂ is from about 4:1 to about 4:3. Preferably, the ratio of partial pressure of hydrogen to partial pressure of CO and/or CO₂ is about 2:1 .

In an embodiment, the oxymethylene ethers comprise, consist, or consist essentially of: OME (dimethoxy methane).

In an embodiment, the oxymethylene ethers comprise, consist, or consist essentially of: OME1 (dimethoxy methane) and one or more oxymethylene ether oligomers of the form OME_n, wherein n is an integer of from 2 to 5. It is preferred that n is a 2 or 3, e.g. OME₂ and OME₃. For avoidance of doubt, OME_n refers to oxymethylene dimethyl ethers of the form CH₃(OCH₂)nOCH3. In an embodiment, the contacting step comprises: contacting a synthesis gas including at least: hydrogen gas, CO, and/or CO₂ with the mixture of methanol and the catalyst.

In an embodiment, the methanol and catalyst are in the form of slurry and the contacting step comprises mixing the synthesis gas with the slurry in the reactor under conditions which promote hydrogenation.

In an embodiment, the hydrogen gas, CO, and/or CO₂ are introduced to a reactor as synthesis gas and the methanol and catalyst is introduced to the reactor as a slurry.

In an embodiment, the process produces oxymethylene ethers from synthesis gas and methanol in a single contacting step.

In a third aspect of the invention, there is provided a catalyst for the production of dimethoxymethane from synthesis gas in a single contacting step comprising: at least one catalytic material selected from the group of Ni, Pt, Ru, Cu and Pd; and at least one acidic catalyst support selected from the group of zeolites, alumina, amorphous silica- alumina, silica and ion exchange resin.

In an embodiment, the at least one catalytic material is at least one catalytic metal selected from the group of Ni(0), Ru(0), Cu(0), Pt(0) and Pd(0).

In an embodiment, the ion exchange resin is an acidic cation exchange resin. Preferably, the acidic cation exchange resin is an acidic sulfonic acid cation exchange resin (e.g. Amberlyst 15 supplied by Dow Chemical).

In an embodiment, at least 2 catalytic metals are used and the support is at least one of the group of zeolites, alumina, amorphous silica-alumina and silica is used in conjunction with the ion exchange resin. The metal/metals may be loaded onto the zeolite, alumina, amorphous silica-alumina or silica and the ion exchange resin is used to increase the acidity of the catalyst/catalyst support.

Further aspects of the present invention and further embodiments of the aspects described in the preceding paragraphs will become apparent from the following description, given by way of example and with reference to the accompanying drawings. Brief description of the drawings

Figure 1 is a schematic representation of the reaction pathway of synthesis gas to dimethoxymethane;

Figure 2 is a graph illustrating the yield obtained from the hydrogenation of CO to dimethoxymethane with 0.5 g Ru/Ni on alumina support and 0.5 g acid catalyst/ ion exchange resin (Amberlyst supplied by Dow Chemical).

Figure 3 is a graph showing the yield obtained from the hydrogenation of CO to dimethoxymethane with a single bifunctional catalyst Ru/Cu on zeolite support.

Figure 4 is a graph showing the yield obtained from the hydrogenation of CO to dimethoxymethane with a single bifunctional catalyst Ru/Ni on a zeolite support.

Figure 5 is a schematic diagram of a system to produce dimethoxymethane via a single contacting step process; and

Figure 6 is a schematic representation illustrating the role of a catalyst or catalysts in the production of dimethoxy methane from hydrogenation of CO. Figure 7 is a graph showing the rate of OME₁ production from hydrogenation of

CO at various temperatures with (a) Ru-Ni/β-zeolite, (b) Ru-Cu/β-zeolite, (c) Β-Νί/β- zeolite, and (d) Ru/ β-zeolite.

Figure 8 is a graph showing the rate of OME_n production from hydrogenation of CO₂ at temperatures (a) 100 °C (b) 125 °C (c) 150 °C (d) 175 °C. Figure 9 is a graph showing the rate of (a) OME₂ (b) OME₃ production from hydrogenation of CO₂ at temperatures (i) 100 °C (ii) 125 °C (iii) 150 °C (iv) 175 °C.

Figure 10 is a graph showing the rate of OMEi production from hydrogenation of CO and CO₂ at 150 °C.

Detailed description of the embodiments It will be understood that the invention disclosed and defined in this specification extends to all alternative combinations of two or more of the individual features mentioned or evident from the text or drawings. All of these different combinations constitute various alternative aspects of the invention.

In one form the invention relates to converting CO and/or CO₂ into oxymethylene ethers in a single contacting step via the use of bifunctional nanomaterial catalyst or catalysts with an acidic support. In embodiments thereof, the OMEs include at least dimethoxymethane (OME or DME), as well as dimethoxymethane oligomers including OME₂ and OME3. The formation of oligomers of dimethoxymethane, is advantageous as these can be more useful than dimethoxymethane as a diesel substitute. In another form, the invention relates to converting either CO or CO₂ into dimethoxymethane (OME-i or DMM) in a single contacting step via the use of bifunctional nanomaterial catalyst or catalysts with an acidic support. The invention uses a slurry phase reaction for hydrogenation of CO or CO2 for the production of OME1 with the aforementioned catalyst or catalysts. This process, which was carried out in a slurry reactor (Figure 3), involves 2 reactions which take place in series (Figure 1 ). The catalyst or catalysts contain metallic sites (e.g. Ni, Ru, Pt, Cu, Pd, Rh or Re. that are dedicated for CO, CO2, and H₂ adsorptions to catalyse the hydrogenation of the CO and CO₂ to formaldehyde and acid sites (e.g. Zeolite, alumina, silicas, amorphous silica-aluminas and ion exchange resin (e.g. Amberlyst 15 available from Dow Chemical)) that further convert intermediate product (formaldehyde) into OME-i . These bifunctional catalyst or catalysts have high adsorption capacity for CO, CO₂ and H₂, are stable within methanol as a solvent and contain acid functional sites which promote OME1 production through dehydration.

The Zeolite Beta 38, Beta 75 and Beta 150 supports are commercially available catalyst supports but others were made in lab via dealumination procedure to modify the acidity. To increase the Si/AI ratio dealumination was carried out by steam treating the as received zeolite beta followed by removal of dislodged aluminium. Preferably at least 2 catalytic metals are used and the support is at least one of the group of zeolites, alumina, amorphous silica-alumina and silica. The support material may comprise the above support material in conjunction with the ion exchange resin. The metal/metals preferably are loaded onto the zeolite, alumina, amorphous silica-alumina or silica and the ion exchange resin is used to increase the acidity of the catalyst/catalyst support.

Catalyst preparation

Described below is a procedure for the preparation of a Ni/Ru catalyst on an alumina substrate.

Nickel nitrate (Ni(NO₃)₂.6H₂O) (0 - 10.0 g), alumina (AI₂O₃) (0 - 20.0 g) and chemicals such as RUCI3 (0 - 0.5 g) were used as the precursors for the catalyst synthesis. First, the required amount of nickel nitrate was measured and dissolved in distilled water. Then, corresponding amount of alumina and metal promoter precursor were added into the solution. To ensure a homogeneous mix of all precursors with alumina, the solution was heated up to 65 °C and maintained for 5hrs under constant stirring. The solutions were then dried overnight in a 100°C oven. Dry solid were recovered and calcined in a muffle furnace at 600 °C for 6 h under air atmosphere.

To activate the catalyst, the catalyst loaded on the support is reduced by heating it to 400°C under H₂/N₂ flow to reduce the metal oxide to pure metal state.

Depending of the metal and catalytic support to be used to make up the bifunctional catalyst, the person skilled in the art would be able to vary the precursor components and metal activation conditions to produce the required combination of catalytic metals loaded onto the support.

To utilise this process, it is necessary to reduce the metal catalyst first as it is naturally in oxide form and will not react. As a heterogeneous catalyst, these bifunctional catalyst or catalysts are not consumed in the reaction process. A build-up of water slows down the reaction and therefore, a process to remove water is required in order to maximise yield. Water can be selectively removed through adsorption with the use of material such as molecular sieve or membrane separation process

As this invention generates OME₁ directly from syngas in a single contacting step, it removes the long complex process currently utilised and increases the efficiency.

Examples

Example 1

The process according to the invention was carried out in accordance with the process flow diagram illustrated in Figure 5. Ex-situ reduced bifunctional catalyst/catalysts was loaded into the reactor along with methanol. These bifunctional catalysts consists of Ni/Ru catalyst with alumina support and acid catalyst- Amberlyst supplied by Dow Chemical. The reactor was first pressurised with high-purity CO and then H₂ based on the required CO:H₂ ratio and its desired pressure (75 bar in this case). The Ni based catalyst was prepared by the impregnation method described earlier and the acid catalyst support was an ion exchange substrate Zeolite or Amberlyst 15). 1 .0 g of catalysts (0.5 g Ni/Ru catalyst on alumina support and 0.5 g acid catalyst/ion exchange resin (Amberlyst 15 supplied by Dow Chemical)) was used and the yield of dimethoxymethane at various temperatures (298 - 373 K) under constant pressure of 75 bar was determined by gas chromatograph. The reaction time was up to around 48 hours. The results are shown in Figure 2.

Experiments similar to the above were performed with a Ru/Cu catalyst on a zeolite. The zeolite was Zeolite beta CP814C supplied by Zeolyst International). Synthesis gas having a CO:H₂ ratio of 1 :2 was combined with a slurry of a Ru/Cu catalyst on a zeolite support containing 0.5g of catalyst. Figure 3 is a graph showing the yield obtained from the hydrogenation of CO to dimethoxymethane with a single bifunctional catalyst Ru/Cu on zeolite support.

Experiments similar to the above were performed with a Ru/Ni catalyst on a zeolite (Zeolite beta CP814C supplied by Zeolyst International). Synthesis gas having a CO:H₂ ratio of 1 :2 was combined with a slurry of a Ru/Cu catalyst on a zeolite support containing 0.5g of catalyst. Figure 4 is a graph showing the yield obtained from the hydrogenation of CO to dimethoxymethane with a single bifunctional catalyst Ru/Ni on a zeolite support.

It can be seen from the examples the dimethoxymethane can be produced by a single contacting step process by contact between synthesis gas containing CO and H₂ with a slurry of bifunctional catalyst and methanol.

Example 2

Catalysts used in this work were synthesized using catalyst preparation method described above. The catalytic activity of the resultant catalysts was evaluated using a slurry batch high pressure autoclave and the yield of OMEs were quantified using a Shimadzu 2014 GC equipped with ZB-1 capillary column.

Five catalysts were tested in this Example, these catalysts were: Ru-Ni/ β- Zeolite, Ru-Cu/ β-Zeolite, B-Ni/ β-Zeolite, Ru-Ni/y-alumina and monometallic Ru/ β- Zeolite.

Figure 7 illustrates the rate of OMEi production from hydrogenation of CO at temperatures of 50 °C, 80 °C, 100 °C, and 120 °C with (a) Ru-Ni/β-zeolite, (b) Ru-Cu/β- zeolite, (c) Β-Νί/β-zeolite, and (d) Ru/ β-zeolite. The reaction conditions used for (a), (b), and (c) include: H₂/CO ratio = 2.00, total pressure = 75 bar at room temperature, stirring speed = 100 rpm, catalyst weight = 0.5 g, solvent = methanol (60 ml), runtime =48 hr. (d) Ru/ β-zeolite. The reaction conditions for (d) include H2/CO2 ratio = 3.00, total pressure = 75 bar at room temperature, stirring speed = 100 rpm, catalyst weight = 0.5 g, solvent = methanol (50 ml), runtime =360 min. Figure 7 shows that OME can be produced with these catalysts in methanol as solvent and hydrogen, carbon oxides as reactants.

Figure 8 compares the rate of production of OME_n (where n=1 , 2, 3) from hydrogenation of CO₂ at (a) 100, (b) 125, (c) 150 and (d) 175 °C with Ru/ β-Zeolite. In this case, the reaction conditions were: H₂/CO₂ ratio = 3.00, total pressure = 75 bar at room temperature, stirring speed = 100 rpm, catalyst = 3% Ru^-zeolite (0.5g), solvent = methanol (50 ml). Figure 8 shows that higher order oligomers of OME_n (e.g. n= 2, 3) were also produced along with OME-i , although, in the later stage of the reaction. This suggests that the higher order oligomers were produced via oligomerization of OME with the formaldehyde produced in situ via hydrogenation of CO and CO₂. Generally, it can be concluded that production rate of OME₂ and OME₃ increased with an increase of temperature as shown in Figure 9.

Figure 9 reports the rate of production of (a) OME₂ (b) OME₃ via hydrogenation of CO₂ at various temperatures. The reaction conditions used were: H2/CO2 ratio = 3.00, total pressure = 75 bar at room temperature, stirring speed = 100 rpm, catalyst = 3% Ru/β-zeolite (0.5g), solvent = methanol (50 ml).

A further study was conducted using a different support material (γ-alumina) to investigate the effect of gas reactant (CO and CO2) on the yield of OME1. The results of this study are summarised in Figure 10.

Figure 10 shows the rate of production of OME from hydrogenation of CO_x at 150 °C. The reaction conditions used were: H₂/CO_x ratio = 2.00, total pressure = 75 bar at room temperature, stirring speed = 100 rpm, catalyst = Ru-Ni/y-alumina (0.5g), solvent = methanol (60 ml). The results in Figure 10 indicate that the production rate of OME was at least one fold higher with CO₂ as reactant. This is thought to be as a result of the higher solubility of CO₂ gas in methanol. It will be understood that the invention disclosed and defined in this specification extends to all alternative combinations of two or more of the individual features mentioned or evident from the text or drawings. All of these different combinations constitute various alternative aspects of the invention.

Claims

1 . A process of producing oxymethylene ethers comprising the steps of: a) contacting hydrogen gas, CO and/or CO₂ with a mixture of methanol and a catalyst at conditions of temperature and pressure to support hydrogenation of the CO and/or CO₂ gas in the synthesis gas to oxymethylene ethers; the catalyst comprising: i. catalytic material being at least one metal selected from the group of Ni, Ru, Cu, Pt and Pd; and ii. an acidic catalyst support being at least one selected from the group of zeolites, alumina, amorphous silica-alumina and silica b) separating the oxymethylene ethers from the catalyst.

2. The process of claim 1 , wherein the catalytic material is at least one metal selected from the group of Ni(0), Ru(0), Cu(0), Pt(0) and Pd(0).

3. The process of claim 1 or 2, wherein the step of contacting the hydrogen gas with CO and/or CO2, it is preferred that the ratio of CO and/or CO2 to hydrogen in the synthesis gas is from 1 :1 to 1 :20.

4. The process of any one of the preceding claims, wherein the contacting step is carried out at a temperature of from about 0°C up to about 200°C.

5. The process of any one of the preceding claims, wherein the contacting step is carried out at a pressure of from about 50 bar up to about 200 bar.

6. The process of any one of the preceding claims, wherein the ratio of partial pressure of hydrogen to partial pressure of CO and/or CO₂ is from about 4:1 to about 4:3.

7. The process of any one of the preceding claims, wherein the oxymethylene ethers comprise: OME1 and one or more oxymethylene ethers oligomers of the form

OMEn, wherein n is an integer of from 2 to 5.

8. The process of claim 7, wherein n is 2 or 3.

9. The process of any one of the preceding claims, wherein the contacting step comprises: contacting a synthesis gas including at least: hydrogen gas, CO, and/or CO2 with the mixture of methanol and the catalyst.

10. The process of any one of the preceding claims, wherein the process produces oxymethylene ethers directly from hydrogen gas and CO and/or CO₂ and methanol in a single contacting step.

1 1 . A process of producing dimethoxymethane comprising the steps of :- a) contacting a synthesis gas of at least CO with a mixture of methanol and a catalyst at conditions of temperature and pressure to support hydrogenation of the CO in the synthesis gas to dimethoxymethane; the catalyst comprising i. catalytic material comprising at least one metal selected from the group of Ni, Pt, Ru, Cu and Pd; and ii. an acidic catalyst support comprising at least one support material selected from the group of zeolites, alumina, amorphous silica-alumina and silica; b) separating the dimethoxymethane from the catalyst.

12. The process of claim 1 1 wherein a further catalyst support material comprising an ion exchange resin may be added into the catalyst support.

13. The process of claim 1 1 wherein the conditions to support hydrogenation of the CO in the synthesis gas to dimethoxymethane is a temperature in the range of 0 - 200°C, preferably 50 - 150°C, and a pressure of 50-200bar.

14. The process of any one of claims 1 1 to 13, wherein the ratio of CO:H₂ in the synthesis gas is in the range of 1 :1 to 1 :20.

15. The process of claim 14 wherein the ration of CO:H₂ is about 1 :2.

16. The process of one of claims 1 1 to 15, wherein the synthesis gas is introduced to a reactor and the methanol and catalyst is introduced to the reactor as a slurry.

17. The process of claim any one of claims 1 1 to 16, wherein the process produces dimethoxymethane directly from synthesis gas and methanol in a single contacting step.

18. A catalyst for the production of dimethoxymethane from synthesis gas in a single contacting step comprising i. catalytic material comprising at least one metal selected from the group of Ni, Pt, Ru, Cu and Pd; and ii. an acidic catalyst support comprising at least one support selected from the group of zeolites, alumina, amorphous silica-alumina and silica.

19. The catalyst of claim 18, wherein the catalyst support further comprises an ion exchange resin.

20. The catalyst of claim 18or 19, wherein the at least one catalytic material is at least one catalytic metal selected from the group of Ni(0), Ru(0), Cu(0), Pt(0) and Pd(0).