New catalysts of Pt, PtNi, PtCo, and NiCo supported on Al2O3 were developed for producing hydrogen by aqueous phase reforming (APR) of oxygenated hydrocarbons. The urea matrix combustion technique was used for loading the metal on the support in order to improve several aspects: increase both the metal-support interaction and the metal dispersion and decrease the metal load. The catalysts were characterized by MS/ICP, N2 adsorption, XRD, TPR, CO chemisorption, and the test of cyclohexane dehydrogenation (CHD). The APR of a solution of 10% mass ethylene glycol (EG), performed in a tubular fixed bed reactor at 498 K, 22 bar, WHSV = 2.3 h−1, was used as the main reaction test. After 10 h on-stream, the catalysts prepared by UMC had better hydrogen yield and catalytic stability than common catalysts prepared by IWI. The UMC/IWI H2 yield ratio was 23.5/15.2 for Pt, 24.0/17.0 for PtCo, 26.6/21.0 for PtNi, and 8.0/3.9 for NiCo. Ni or Co addition to Pt increased the carbon conversion while keeping the H2 turnover high. Cobalt also improves stability. Reports of several authors were revised for a comparison. The analysis indicated that the developed catalysts are a viable and cheaper alternative for H2 production from a renewable resource.
Current methods of industrial hydrogen production used in petroleum refineries require high temperatures, about 800 K in the case of naphtha reforming [
Nowadays, a growing need exists for processing heavy crudes with a high content of heteroatoms and polyaromatic molecules. Large amount of hydrogen is needed for the hydrotreatment of biomass-derived oxygenates. Many works about the hydrodeoxygenation of lignin-derived phenolic have been reported [
The burning of fossil fuels has a major impact on the increase of the concentration of CO2 in the atmosphere. On the contrast, energy derived from biomass releases carbon with a carbon-energy ratio similar to that of coal. However, as indicated by Wuebbles and Jain [
The aqueous phase reforming (APR) of oxygenated hydrocarbons derived from biomass is considered a promising alternative process for supplying great amounts of hydrogen at a conveniently low cost. Biomass reforming also has a neutral CO2 life cycle, making it convenient from an environmental point of view. APR of oxygenated hydrocarbons can also be performed at low reaction temperatures, for example, 500 K, thermodynamically favoring hydrogen formation with low carbon monoxide content. An overview of aqueous-phase catalytic processes for production of hydrogen and alkanes in a bio refinery has been shown by Huber and Dumesic [
One of the key aspects of the APR technology is the design of a suitable catalyst. Many reports study catalysts based on supported Pt. These reports highlight the influence of the amount of available metal surface on the overall activity and the selectivity to hydrogen. Thus, best-performing catalysts have high Pt surface areas per unit catalyst mass. Due to the difficulties of achieving and maintaining a high metal dispersion, most current Pt catalysts for APR have great Pt loads and high associated costs. One way of reducing the catalyst cost is to partially or totally replace Pt by another transition metal with similar properties. For instance, Ni provides good hydrogen yields in gas phase reforming. However, Davda et al. [
Shabaker et al. [
González-Cortés et al. [
Another issue is that of the choice of the support. Different groups have obtained catalysts with high hydrogen yields, but they not only use high Pt loads but also use special supports [
Most APR catalysts have high fabrication costs. In this sense, the focus of the present work is put on the comparison of the catalysts of this work, which have relatively low metal content, with those prepared by conventional methods that have been reported in the open literature. The aim is to obtain similar properties as those of these reported catalysts.
The catalytic properties are compared of reference Pt, PtNi, PtCo, and NiCo catalysts supported on alumina, prepared by a classical method (incipient wetness impregnation of the precursor solutions on gamma alumina) with catalysts of similar composition prepared by the UMC technique. Properties studied are activity, hydrogen yield, selectivity, hydrogen turn-over frequency
Two different methods were used to incorporate the metals to the support: (i) the common simultaneous incipient wetness impregnation (IWI) of the metal precursors, followed by slow calcination; (ii) the method of simultaneous wet impregnation of the metal precursors with urea, followed by the fast combustion of the urea matrix (UMC) [
In the case of the IWI route, the support was dried in a stove at 383 K for 12 h after impregnation and was then slowly heated from room temperature to 723 K (10 K·min−1), then kept and calcined at this temperature for 3 h in flowing air (30 cm3·min−1). In the case of the UMC route, a solution was prepared that contained urea and the metal precursors with a ratio of 10 mol urea per mol of metal (all metals). The pH of the solution was adjusted to 7, and then the support was immersed in the solution. The system was stirred gently for 3 h at 323 K. The solution excess was evaporated at 323 K until a slurry was formed, and then it was quickly calcined for 10 min at 773 K [
Mono and bimetallic catalysts were identified according to the following description: Pt-IWI; PtNi-IWI; PtCo-IWI, NiCo-IWI, Pt-UMC; PtNi-UMC; PtCo-UMC; and NiCo-UMC. The UMC and IWI acronyms indicate the preparation route used.
The concentration of the supported metals (Pt, Ni, and Co) in the catalysts was determined by mass spectroscopy with inductively coupled plasma (MS/ICP). The equipment used was an ARL 3410 with argon as gas for the plasma. The solid sample was dissolved in a sulphuric acid solution (50% vol.), and then an aliquot was placed in the nebulizer of the ICP, and the concentration of the metal cations was determined from the mass spectrum of the ion source, as measured by means of a quadrupole mass spectrometer.
The concentration of exposed metal sites was determined using CO as a molecular probe. CO selectively chemisorbs on the surface metal atoms of the metal particles. For this test, an amount of 0.05 g of reduced catalyst was used. Calibrated pulses of a CO : N2 mixture (1.46% CO in N2, molar basis) were sent to the reactor cell until the metallic surface became saturated. The nonadsorbed CO was converted to CH4 with H2 over a Ni/Kieselguhr catalyst and detected by a flame ionization detector connected to the exhaust of the reactor. The adsorbed CO was determined from a mass balance.
The specific surface area was measured in a volumetric system from the N2 adsorption isotherm obtained at 77 K. The specific surface area (BET method) and porosity measurements were performed in a model ASAP 2020 Micromeritics apparatus using 0.3 g of sample. Samples were outgassed by heat under vacuum (1.333 10−9 bar) at 523 K for 30 h before the nitrogen adsorption.
X-ray diffraction tests were performed in an XD-D1 Shimadzu diffractometer. A sample of about 0.3 g was dried in an oven and then ground to a powder. Then, it was placed on a sample holder and irradiated with Cu K
The temperature-programmed reduction technique (TPR) allows the study of the reducibility of the surface species on the solid support and the degree of interaction between them, especially metal-metal, metal-promoter, and metal-support interactions. Reducibility was measured by H2 consumption as the sample was subjected to a heating schedule. An Ohkura TP 2002s equipment with a thermal conductivity detector (TCD) was used for these experiments. A known mass of catalyst was first treated in flowing air at 723 K for 1 h and then brought to room temperature. Then the sample was flushed with flowing Ar for 15 min, and the reducing mixture (5% H2 in Ar) was passed over the sample at room temperature. Once the system was stabilized, the temperature was raised linearly from room temperature to 973 K at a heating rate of 10 K min−1.
The cyclohexane dehydrogenation (CHD) reaction test allows evaluating the metallic phase of the catalyst. This reaction is known to proceed with a rate that is strictly proportional to the number of surface metal sites, with no regards to metal particle size or surface atom location. This means this reaction is not sensitive to the catalyst structure [
Aqueous-phase reforming of ethylene glycol was performed in a tubular stainless steel AISI 316L reactor of 9.5 mm internal diameter and of 1.5 mm thickness, heated by an electric oven. The system had a similar configuration as that used by Shabaker et al. [
This is not the common definition of yield but is that used by Dumesic and coworkers. It has been adopted here for the sake of comparison. “H2
For calculation both (
Selectivity to carbon products (CP) in the gas products (CO, CO2, CH4):
Other parameter calculated was the turn-over frequency for hydrogen production (
The stability of the APR catalytic system is limited by three main factors: fouling by coke, sintering, and leaching of the metallic phase. The deactivation by coking was assessed by temperature programmed oxidation (TPO) of the coke deposit of the spent catalysts. An amount of 0.05 g of deactivated catalyst was first loaded into a quartz reactor, and then an oxidizing gas mixture (2% O2 in N2, molar basis, 30 cm3·min−1 flow rate) was forced through the sample. The reactor was heated at a rate of 10 K·min−1 from room temperature up to 973 K. In the presence of oxygen, the deposits were combusted to CO and CO2. Both gases were transformed into methane over a Ni/kieselguhr catalyst in a methanation reactor and then sent to a flame ionization detector. The TPO trace was thus obtained by registering the FID voltage as a function of the cell temperature. The area under the signal is proportional to the amount of deposited coke. The sintering of the metal phase affects directly the WGS reaction, and it was indirectly assessed by the hydrogen yield obtained at a fixed reaction time. The leaching of active sites was determined by chemical analysis of the used catalyst at the end of each experiment. The analysis was performed by inductively coupled plasma with mass spectroscopy detection (ICP-MS).
To compare the stability of the catalysts, the fouling deactivation rate (after a stabilization period of 3 h) and leaching deactivation rate were calculated as follows:
The technology of aqueous phase reforming (APR) has been specially developed by Randy Cortright and James Dumesic of the University of Wisconsin [
In order to make a comparison, a literature survey was made and data collected related to APR over Pt/Al2O3 catalysts. Catalysts with a similar or higher loading of metal phase were considered (in comparison with the catalysts of this work). Data were also collected corresponding to APR catalysts that used similar metal contents but different supports.
Table
Chemical composition, CO chemisorption, H2 consumption in TPR test, and specific surface area (Sg).
Catalyst | Pt (%) | Co (%) | Ni (%) |
|
|
Sg (m2/g) | ConversionCH to Bz (%) |
---|---|---|---|---|---|---|---|
Pt-IWI | 0.98 | — | — | 48.7 | 335.1 | 215 | 93.4 |
Pt-UMC | 0.99 | — | — | 49.4 | 460.8 | 210 | 95.4 |
PtCo-IWI | 1.02 | 3.05 | — | 25.0 | 496.8 | 193 | 67.3 |
PtCo-UMC | 0.97 | 2.87 | — | 34.0 | 846.1 | 201 | 79.1 |
PtNi-IWI | 1.01 | — | 3.10 | 18.6 | 668.4 | 200 | 52.0 |
PtNi-UMC | 0.99 | — | 2.96 | 27.1 | 803.9 | 206 | 79.5 |
NiCo-IWI | — | 3.05 | 2.95 | 35.2 | 755.4 | 197 | 20.3 |
NiCo-UMC | — | 2.99 | 2.87 | 50.9 | 993.1 | 192 | 34.1 |
Cyclohexane to benzene conversion (ConversionCH to Bz) after 1 h on-stream in a dehydrogenation test.
It can be seen that the Ni, Co, and Pt mass contents are similar to the nominal contents. The metal charge does not substantially modify the specific surface of the catalysts. Nitrogen adsorption measurements indicate that the BET surface area of the catalysts varies no more than 8% in comparison to the original value of the metal-free support. The metal addition step is then supposed to occur without blocking of the pore mouths of the catalysts. This points out to a high efficiency of both methods (UMC and IWI) for loading the metals to the support, with negligible loss of metal mass or support-specific area. The results of chemisorption of CO have double importance. First, the CO chemisorption capacity is proportional to the dispersion of the metal. Secondly, CO adsorption is the first step for the water gas shift reaction that results in an increased production of hydrogen. The results indicate that the monometallic Pt catalysts, prepared either by IWI or UMC, have the highest capacity for CO chemisorption, that is, the highest metal particle dispersion. The CO chemisorption capacity of the bimetallic PtNi and PtCo catalysts is lower than the capacity of the monometallic Pt catalysts. The order of CO chemisorption capacity of the catalysts is Pt > PtCo > PtNi. These results coincide with the reports of Ko et al. [
The X-ray powder diffraction patterns of the prepared catalysts are shown in Figure
X-ray diffractograms of the studied catalysts.
We can see that all catalysts exhibited the peaks of gamma alumina at 2
TPR traces of the tested catalysts can be seen in Figure
TPR traces of the tested catalysts.
For the PtNi-IWI and PtNi-UMC catalysts, two different peaks are seen. The first one, located at 415–515 K could be related to the reduction of PtOx species interacting with the oxygen atoms of Al2O3 and NiO, reduced by the spillover effect of H2 over Pt. In the catalyst prepared by UMC, a shift to lower temperatures in the reduction peak of Pt species is found. On the contrast, the peak at 875 K is related to the reduction of nickel species. This could be NiO weakly interacting with the Al2O3 support (
The TPR traces of NiCo-IWI and NiCo-UMC catalysts had peaks at 440 K, 590–640 K, and 975 K. Reduction peaks at temperatures below 773 K are related to the reduction of nickel and cobalt ions to metallic Ni and Co. It is suggested by Nabgan et al. [
Summarizing the characterization results, we can observe that for the same metal loading, the UMC technique permits obtaining catalysts with a higher CO-chemisorption capacity, with more dispersed metal particles and with a greater specific area. A higher metal activity for dehydrogenation was also obtained. These results would confirm the possibility of obtaining catalysts of similar catalytic performance but with lower noble metal concentration.
A plot of the hydrogen yield as a function of time-on-stream can be seen in Figure
Hydrogen yield of the different catalysts. APR of ethylene glycol (10% aqueous solution). Fixed bed reactor, 498 K 22 bar, WHSV = 2.34 h−1, LHSV = 0.86 h−1.
The numerical results of the catalytic properties at the end of the run indicate (Table
Results of APR of aqueous ethylene glycol (10% w).
Catalyst | ConversionC to gas, (%) | Selectivity (%) | H2 yield (%) |
|
|
---|---|---|---|---|---|
CH4 | H2 | ||||
Pt-IWI | 42.9 | 2.0 | 35.4 | 15.2 | 1.01 |
Pt-UMC | 65.0 | 1.7 | 36.2 | 23.5 | 1.53 |
PtCo-IWI | 64.0 | 0.7 | 26.6 | 17.0 | 2.19 |
PtCo-UMC | 86.0 | 0.6 | 27.9 | 24.0 | 2.27 |
PtNi-IWI | 80.0 | 6.7 | 26.3 | 21.0 | 3.13 |
PtNi-UMC | 86.0 | 4.6 | 30.9 | 26.6 | 3.16 |
NiCo-IWI | 24.0 | 11.4 | 16.3 | 3.9 | 0.36 |
NiCo-UMC | 48.0 | 12.7 | 16.7 | 8.0 | 0.51 |
Results at 10 h on-stream. Reaction conditions: 498 K, 22 bar, WHSV = 2.34 h−1, and LHSV = 0.86 h−1.
The total time-on-stream of the APR tests was 10 h. On average PtNi-UMC, PtCo-UMC, and Pt-UMC had higher H2 yields and TOFH2 than Pt-IWI. The catalyst PtNi-UMC had the best hydrogen yield. PtCo-UMC had better yields up to 400 min of time-on-stream, its activity level then becoming similar to that of Pt-UMC. All catalysts show growing hydrogen yields along the run, then stabilizing after 500 min on-stream. This is coincident with the report of Luo et al. [
It can also be seen that once the catalysts reach a pseudo steady state, the hydrogen yield values become higher than that of the Pt-IWI catalyst. The difference is 50% for Pt-UMC and PtCo-UMC and 75% for PtNi-UMC. Also for an equal yield to hydrogen, the PtCo-UMC catalyst has a lower selectivity to methane than the Pt-UMC catalyst. Bimetallic PtNi catalysts are the most active and show the highest values of TOFH2. However, their selectivity to methane is high, that is, they consume part of the H2 produced.
Table
Stability of the catalysts in APR of aqueous ethylene glycol (10%w).
Catalyst | MetalT] |
104 × |
CokeT] |
104 × |
||
---|---|---|---|---|---|---|
0 h | 10 h | 3 h | 10 h | |||
Pt-IWI | 0.98 | 0.97 | 0.1 | 1.3 | 1.9 | 8.6 |
Pt-UMC | 0.99 | 0.98 | 0.1 | 0.9 | 1.2 | 4.3 |
PtCo-IWI | 4.07 | 4.01 | 0.6 | 1.2 | 1.4 | 2.8 |
PtCo-UMC | 3.84 | 3.82 | 0.2 | 1.1 | 1.2 | 1.4 |
PtNi-IWI | 4.11 | 4.03 | 0.8 | 2.8 | 3.6 | 11.4 |
PtNi-UMC | 3.95 | 3.90 | 0.5 | 2.8 | 3.4 | 8.6 |
NiCo-IWI | 6.00 | 5.92 | 0.8 | 2.4 | 3.4 | 14.3 |
NiCo-UMC | 5.86 | 5.83 | 0.3 | 2.5 | 2.7 | 2.9 |
Reaction conditions: 498 K, 22 bar, WHSV = 2.34 h−1, LHSV = 0.86 h−1, and TOS = 10 (
Regarding leaching, although the variations of the results are within the experimental error of the analysis technique, there is a trend that confirms a stronger anchorage of the metallic particles in the catalysts prepared by UMC with respect to those obtained by the conventional IWI technique. Regarding fouling, the Pt-UMC and the PtCo-UMC catalysts had the lowest coke content. Coke content was below 2% after 10 h on-stream. Pt-UMC had the lowest amount of coke at 3 h on-stream. The Ni-containing catalysts had the highest amount of coke at short and long reaction times. For any of the catalysts, not less than 60% of the total coke was formed in the first 3 h of reaction. This indicates that after the catalyst is stabilized, the coking reactions become slower, probably because of deactivation of the sites of higher coking activity.
After 3 h of reaction, the coke on the metal is stabilized, and the deactivation rate due to fouling is minimal in the samples promoted with cobalt, both in PtCo and in NiCo. The fouling rate increases in the samples with nickel. This trend is more pronounced in the catalysts prepared by UMC.
Figure
Temperature-programmed oxidation traces of different catalysts. Catalyst coked during a test of 10 h (APR of aqueous ethylene glycol, 10%).
It can be seen in all cases that coke is burned at temperatures lower than 873 K. The incorporation of Ni into Pt generates a more hydrogenated deposit giving a very sharp coke burning peak. Despite having accumulated the largest amount of coke, its steady-state activity is the largest. The incorporation of Co to Pt reduces the amount of coke and reduces the degree of polymerization, coke being eliminated in a lower temperature range. If we compare the coke deposits obtained on catalysts of the same composition but synthesized by different methods, a reduction of the coke content on the UMC catalysts can be seen. The degree of metal dispersion obtained by each preparation route evidently modifies the stability of the catalyst.
In 2002, the group of Professor Dumesic of the University of Wisconsin developed a catalytic process that generated H2 from the aqueous-phase reforming (APR) of biomass-derived oxygenated compounds such as methanol, ethylene glycol, glycerol, sugars, and sugar-alcohols [
We can see in Table
Results of APR of ethylene glycol over different catalysts.
Catalyst | EG (% w) |
|
|
WHSV (h−1) | LHSV (h−1) | ConversionC to gas (%) | Selectivity (%) | H2 yield (%) |
|
Reference | |
---|---|---|---|---|---|---|---|---|---|---|---|
C5− | H2 | ||||||||||
Pt(3)/Al2O3 | 1 | 498 | 29.3 | 0.6 | 90.0 | 4.0 | 96.0 | 86.4 | 5.3 | Shabaker et al. [ | |
R-Ni(14)Sn | 1 | 498 | 25.8 | 5.1 | 93.0 | 4.0 | 95.0 | 88.4 | 1.4 | Shabaker et al. [ | |
Pt(1) | 10 | 498 | 29.3 | 72.0 | 5.4 | 1.2 | 87.1 | 4.7 | 1.9 | Huber et al. [ | |
Pt(1)Ni(1) | 10 | 498 | 29.3 | 70.2 | 5.9 | 0.0 | 91.0 | 5.4 | 5.2 | Huber et al. [ | |
Pt(1)Ni(5) | 10 | 498 | 29.3 | 138.5 | 3.6 | 0.9 | 89.5 | 3.2 | 3.0 | Huber et al. [ | |
Pt(1)Ni(8) | 10 | 498 | 29.3 | 128.6 | 3.5 | 2.0 | 90.2 | 3.2 | 2.8 | Huber et al. [ | |
Pt(1)Co(5) | 10 | 498 | 29.3 | 57.4 | 8.4 | 0.5 | 88.2 | 7.4 | 5.1 | Huber et al. [ | |
Pt(1.5)/Al2O3 | 1 | 548 | 200.0 | 1.2 | 78 | 0.3 | De Vlieger et al. [ | ||||
Pt(1.5)/Al2O3 | 20 | 723 | 250.0 | 12 | 74 | 16.9 | De Vlieger et al. [ | ||||
Ni(19)/SiO2 | 10 | 498 | 22.0 | n/r | 2.3 | 13.0 | 57.0 | 1.3 | 14.0 | Davda et al. [ | |
Pd(5)/SiO2 | 10 | 498 | 22.0 | n/r | 3.1 | 0.0 | 98.5 | 3.0 | 30.0 | Davda et al. [ | |
Pt(6)/SiO2 | 10 | 498 | 22.0 | n/r | 21.0 | 13.0 | 77.9 | 16.4 | 275.0 | Davda et al. [ | |
Ru(6)/SiO2 | 10 | 498 | 22.0 | n/r | 42.0 | 58.0 | 7.0 | 2.9 | 20.0 | Davda et al. [ | |
Pt(1)/CMK-3 | 10 | 523 | 45.6 | 2.0 | 25.4 | 4.5 | n/r | 26.6 | 103 | Kim et al. [ | |
Pt(3)/CMK-3 | 10 | 523 | 45.6 | 2.0 | 46.0 | n/r | n/r | 49.3 | 46.4 | Kim et al. [ | |
Pt(7)/CMK-3 | 10 | 523 | 45.6 | 2.0 | 69.8 | 7.1 | n/r | 72.1 | 31.2 | Kim et al. [ | |
Pt(3) CMK-9 | 10 | 523 | 45.6 | 2.0 | 44.9 | 4.2 | n/r | 49.3 | n/r | Kim et al. [ | |
Fe(3) CMK-9 | 10 | 523 | 45.6 | 2.0 | 12.1 | 8.9 | n/r | 27.1 | n/r | Kim et al. [ | |
Pt(3)Fe(3) (1 : 1) | 10 | 523 | 45.6 | 2.0 | 60.8 | 3.3 | n/r | 64.9 | n/r | Kim et al. [ | |
Pt(3)Fe(6) (1 : 2) | 10 | 523 | 45.6 | 2.0 | 63.2 | 3.1 | n/r | 66.7 | n/r | Kim et al. [ | |
Pt(3)Fe(9) (1 : 3) | 10 | 523 | 45.6 | 2.0 | 68.4 | 2.8 | n/r | 71.1 | ∼70-80 | Kim et al. [ | |
Pt(3)Fe(12) (1 : 4) | 10 | 523 | 45.6 | 2.0 | 60.1 | 2.6 | n/r | 70.7 | n/r | Kim et al. [ | |
Pt(3)Fe(15) (1 : 5) | 10 | 523 | 45.6 | 2.0 | 58.9 | 2.7 | n/r | 68.8 | n/r | Kim et al. [ |
Steady state conditions, fixed bed reactor.
Shabaker et al. [
Recent studies on Pt supported over carbon nanotubes for the aqueous phase reforming of ethylene glycol showed that the activity can be greatly improved by changing the support to a more convenient one [
Finally, with a similar support, Kim et al. [
At the APR reaction, conditions of this work Pt/Al2O3 catalysts prepared by incipient wetness impregnation (IWI) show a hydrogen yield of about 15.2%. The addition of 3% Ni or Co and the use of a different method of metal addition (urea matrix combustion, UMC) produce catalysts that have a higher yield to hydrogen and a higher stability and a lower selectivity to coke and methane. Particularly, the addition of Co by UMC increases the hydrogen yield by 50% in relation to the standard Pt/Al2O3 catalyst, while keeping similar hydrogen selectivity and a much lower selectivity to methane. The addition of Ni by UMC increases the hydrogen yield by 75% in comparison to the standard Pt/Al2O3 catalyst but increases both the methanation and coking activities.
The simultaneous use of the UMC method and Ni and Co promotion enabled the synthesis of APR catalysts that had a lower metal content than those reported in the literature, but a similar or better activity level.
The decrease of the selectivity to the undesired products such as coke and methane enabled an increase of the conversion by a factor of two and of the hydrogen yield by a factor of 1.5.
A comparison with published results indicates that catalysts of other authors obtained similar or better results than ours, but with the use of higher metal contents or more expensive supports. In some cases, their experiments were carried out with diluted solutions of ethylene glycol or higher reaction temperatures and pressures, conditions that are associated with higher operation costs.
In summary, APR catalyst of low noble metal content and hence of low cost can be obtained by using the UMC method to incorporate Ni or Co promoters to alumina supported Pt catalysts. These catalysts show promising catalytic properties for the improved production of H2 by APR of biomass related feedstocks.
The data used to support the findings of this study are available from the corresponding author upon request.
There are no conflicts to declare.
The authors thank Sasol for the donation of alumina used in this paper. The authors also thank the financial support of CONICET (PIP Grant 2014-560), Universidad Nacional delLitoral (CAI+D Grant 2016-084), and ANPCyT (PICT Grant 2013–3217).