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Chemical looping is investigated for the production of syngas via reforming or reverse water gas shift in a packed bed reactor using 500 g of Fe on Al2O3 was demonstrated. Oxidation, reduction of the OC and subsequent catalytic reactions of reforming or reverse water gas shift were examined in a temperature range of 600–900 °C and a pressure range of 1–3 bara at high flowrate. Different inlet gas compositions were explored for the considered gas–solid and catalytic reaction stages. Oxidation with air successfully heated the reactor. CH4 resulted ineffective at reducing the Fe-based oxygen carrier while H2 and CO-rich stream were able to achieve full reduction to FeO of the material. In terms of catalytic activity, the maximum conversion of CH4 achieved during the reforming was limited to 62.8 % at 900 °C and 1 bara. Thermally integrated chemical looping reverse water gas shift was studied as option for CCU in combination with green H2 to produce renewable fuels. A H2/CO value of 2 could be achieved by feeding H2/CO2 of 2. The pressure did not substantially affect the conversion and the bed did not present carbon deposition. The ability of a Fe-based packed bed chemical looping reactor to recover after the carbon deposition was also explored. It was found that using a mixture of CH4 and CO2 achieved 92% recovery of the original capacity.

Platinum functions exceptionally well as a nanoparticulate catalyst in many important fields, such as in the removal of atmospheric pollutants, but it is scarce, expensive and not always sufficiently durable. Here, we report a perovskite system in which 0.5 wt% Pt is integrated into the support and its subsequent conversion through exsolution to achieve a resilient catalyst. Owing to the instability of most Pt oxides at high temperatures, a thermally stable platinum oxide precursor, barium platinate, was used to preserve the platinum as an oxide during the solid-state synthesis in an approach akin to the Trojan horse legend. By tailoring the procedure, it is possible to produce a uniform equilibrated structure with active emergent Pt nanoparticles strongly embedded in the perovskite surface that display better CO oxidation activity and stability than those of conventionally prepared Pt catalysts. This catalyst was further evaluated for a variety of reactions under realistic test environments—CO and NO oxidation, diesel oxidation catalysis and ammonia slip reactions were investigated. Nanoparticulate platinum is a highly active catalyst, but it is scarce, expensive and not always sufficiently durable. Now, barium platinate has been used as a vehicle to preserve platinum as an oxide during the solid-state synthesis of a Pt-doped titanate perovskite; this enables the production of a structure with active and stable Pt nanoparticles on the perovskite surface that catalyses CO oxidation.

Chemical looping reforming (CLR) is a promising technology for syngas production combining autothermal operation with integrated CO2 capture. At large scale, reformer outlet pressure during syngas production is an important factor for the overall plant’s process efficiency and defines the energy requirements for downstream processing. Packed bed reactors are widely used and established in industry for high pressure operating conditions due to their robust and, compared to other reactor types, simpler engineering. In this paper, CLR in packed bed reactors (CLR-PB) is demonstrated under a pressure range of 1 – 5 bar in a lab scale reactor, using NiO/CaAl2O4 as the oxygen carrier (OC). Oxidation, reduction and dry reforming processes were examined in a wide range of temperature (400 – 900 °C), pressure (1 – 5 bar), flowrate (10 – 40 NLPM) and different inlet gas compositions, providing an important foreground for the optimal operating conditions for each process.Furthermore, a full CLR-PB pseudo-continuous cycle has been successfully demonstrated for the first time in a lab reactor setup. During the full cycle operation, CH4 conversion > 99% has been achieved, while the temperature and concentration profiles provided identical results for consecutive cycles verifying the continuity and the feasibility of the process. These results constitute the basis for the scale-up of the process, where heat losses would be minimized and the energy efficiency of the process would be significantly higher.

Distributed hydrogen generation from liquid fuels has attracted increasing attention in the past years. Petroleum-derived fuels with already existing infrastructure benefit from high volumetric and gravimetric energy densities, making them an interesting option for cost competitive decentralized hydrogen production.In the present study, direct steam reforming of diesel and diesel blends (7 vol.% biodiesel) is investigated at various operating conditions using a proprietary precious metal catalyst. The experimental results show a detrimental effect of low catalyst inlet temperatures and high feed mass flow rates on catalyst activity. Moreover, tests with a desulfurized diesel–biodiesel blend indicate improved long-term performance of the precious metal catalyst. By using deeply desulfurized diesel (1.6 ppmw sulfur), applying a high catalyst inlet temperature (>800 °C), a high steam-to-carbon ratio (S/C = 5) and a low feed mass flow per open area of catalyst (11 g/h cm2), a stable product gas composition close to chemical equilibrium was achieved over 100 h on stream. Catalyst deactivation was not observed.

Tail pipe emission reduction, increased use of renewable fuels and efficient supply of auxiliary power for road vehicles using fuel cells have been the main drivers of the European project BIOFEAT (biodiesel fuel processor for a fuel cell auxiliary power unit for a vehicle). Within the project a biodiesel fuelled heat integrated fuel processor for 10 kW e capacity has been designed and constructed. Demonstration tests showed a high quality reformate with less than 10 ppm of CO and a gross efficiency of 87%.

Recently, liquid biofuels have attracted increasing attention as renewable feedstock for hydrogen production in the transport sector. Since the lack of hydrogen infrastructure and distribution poses an obstacle for the introduction of fuel cell vehicles to the market, it is reasonable to consider using liquid biofuels for on-board or on-site hydrogen generation. Biodiesel offers the advantage of being an environmentally friendly resource while also having high gravimetric and volumetric energy density.The present study constitutes an experimental investigation of biodiesel steam reforming, the main emphasis of which is placed on finding optimum operating conditions in order to avoid catalyst deactivation. Temperature was varied from 600 °C to 800 °C, pressure from 1 bar to 5 bar and the molar steam-to-carbon ratio from 3 to 5. Based on the experimental results, coke formation and sintering are identified as the main deactivation mechanisms. Initiation of catalyst deactivation primarily depends on catalyst inlet temperature and feed mass flow per open area of catalyst. By using a metallic based precious metal catalyst, applying low feed flow rates (31 g/h∙cm2) and a sufficiently high catalyst inlet temperature (>750 °C) coking can be minimized, thus avoiding catalyst deactivation. A stable product gas composition close to chemical equilibrium has been achieved over 100 h with a biodiesel conversion rate of 99%.

Alumina was synthesized by a sol–gel method using modifying agents such as 2,4-pentanedione, acetophenone, benzophenone, and dibenzoyl methane. The alumina supports were characterized employing N 2 adsorption studies and 27 Al solid-state NMR. The ZnCl 2 /Al 2 O 3 catalysts were made by impregnation of methanolic solution containing calculated amounts of ZnCl 2 on modified alumina supports. The influence of the loading of ZnCl 2 and also the effect of additive used during the sol–gel synthesis of alumina, were probed using Friedel–Crafts alkylation reaction. The alkylation activities indicated the predominance of pore volume in determining the catalytic activities of the catalysts, rather than pore size distribution.

ZnCl2–aluminosilicate catalysts were prepared via a sol–gel route involving fluoride‐catalyzed hydrolysis of aluminum and silicon alkoxides in the presence of NaF, KF, NH4F and ZnF2. The catalysts were characterized by employing 29Si, 27Al and 19F solid‐state MAS NMR. The dependence of the activities of the catalysts on the nature and amount of fluoride present in the catalysts were investigated using Friedel–Crafts alkylation reaction of benzene with benzyl chloride.

Novel mesoporous silicas have been prepared via a sol-gel route involving fluoride-catalyzed hydrolysis of tetraethylorthosilicate (TEOS). Incorporation of zinc chloride by sol-gel synthesis gives a range of mesoporous materials with significantly higher catalytic activity than the commercially available catalyst, Clayzic, in a model Friedel-Crafts alkylation reaction. The dependence of catalytic activity and physical structure on the amounts of solvent, water, zinc chloride, and potassium fluoride used in the preparation are explored, and the materials have been further characterized by nitrogen adsorption to determine surface areas, total pore volumes, and pore-size distributions and by 29Si and 19F MAS NMR spectroscopy. The most active catalysts generally have the highest total pore volumes, with pore-size distributions larger than 8 nm.Key words: sol-gel, Friedel-Crafts, Clayzic, silica.

Aluminosilicates have been prepared from aluminium tri-sec-butoxide and tetraethyl orthosilicate in butanol incorporating transition metal pentane-2,4-dionate complexes, which on calcination give active Friedel–Crafts alkylation catalysts having texturalmesoporosity. Addition of β-diketonates to the aluminosilicate sol–gel results in complexation to aluminium which, on calcination,generates a mesoporous aluminosilicate with increased surface area and pore volume. This provides a suitable framework upon which zinc chloride may be supported at higher loadings than for either the unmodified material or K10, the support for the commercial catalyst Clayzic, to give materials with significantly higher catalytic activity in a Friedel–Crafts alkylation reaction.

Aluminosilicate catalyst supports have been prepared from aluminium tri-sec-butoxide and tetraethyl orthosilicate in butanol using sol–gel methodologies, thereby providing useful supports for zinc chloride, to generate heterogeneous Friedel–Crafts alkylation catalysts. The optimum loading for these sol–gel-derived materials is higher than that of K10, the support for the commercially available catalyst ‘Clayzic’, and gives significantly higher catalytic activity in a standard test reaction. A more convenient, ‘one-pot’ approach, in which zinc chloride is added during the sol–gel synthesis, generates catalysts which also show significantly higher activity than Clayzic. The resulting materials have been characterized by 29 Si cross-polarization magic-angle spinning (CP-MAS) and 27 Al MAS NMR, IR spectroscopy and by surface area and pore volume analysis. The Si:Al ratio, drying temperature and relative amounts of water and (non-aqueous) solvent have pronounced effects on catalytic activity. The most active catalysts show relatively high levels of framework aluminium species compared with non-framework sites, and also have higher surface areas and pore volumes than materials with lower activity.

Production of hydrogen on-board an airplane, to feed a fuel cell secondary power generation unit, is realisable by catalytic partial dehydrogenation of kerosene. The influence of the nature support on the partial dehydrogenation of Ultra Low Sulfur Kerosene Jet A-1 using Pt-Sn based catalysts is investigated in this work. The doping of an alumina support with barium oxide leads to a catalyst providing a productivity of 2000 NL H2 kg cat −1 h −1 with H 2 purity of 97 vol.%.

Fluorodenitration of nitro-substituted diphenyl sulphones occurs readily in dipolar aprotic solvents using tetramethylammonium fluoride as the source of fluoride, although other reactions including fluorodesulphonylation can sometimes occur in competition.

The partial dehydrogenation (PDh) of hydrocarbon blends may be a suitable way to produce H2 on-board of automotives or airplanes to feed fuel cells and produce electric power, avoiding storage problems. In this work very interesting data have been collected using Jet A-1 surrogate and Pt–Sn/γ-Al2O3 catalysts, operating at 450 °C and feeding the vaporised hydrocarbon blend without any carrier gas. The use of Pt/Sn catalyst with 1:1 (w/w) ratio leads to the best compromise between activity and stability with time-on-stream, due to the formation of Pt-rich alloys. Nevertheless, all studied catalysts exhibited limited thio-tolerance. In optimized reaction conditions, H2 productivity of 3000 NL/kgcat/h, sufficient to produce 3 kW of electric power, considering purification steps and a fuel efficiency of 50%, was obtained.

The partial dehydrogenation of fuels like diesel or kerosene cuts to produce H 2 is an emerging idea of increasing interest. In the present work the study of the partial dehydrogenation of Jet A-1 fuel on Pt–Sn/γ-Al 2 O 3 based catalysts to produce H 2 to feed an on-board (aircraft) proton exchange membrane fuel cell is presented. Extensive physico-chemical characterization of 5% wt.Pt-1% wt.Sn/γ-Al 2 O 3 and 5%wt.Pt-1%wt.Sn-1%wt.Na/γ-Al 2 O 3 pelleted materials has been performed. A gradient of the active metals from the edge to the centre of the pellet has been observed. A higher concentration of Pt 0 has been detected on the outer part of the pellet than in the inner part, whereas Sn has been detected only on the external part of the pellet. The investigated materials are active as catalysts for the partial dehydrogenation of normal and desulfurised Jet A-1 kerosene fuel. The presence of sulfur compounds and coke deposition strongly affects the H 2 productivity which decreases rapidly with time on stream. The presence of a Na cation addition contributes to give the highest and most sustained H 2 production. The condensed outlet liquid stream retains the fuel properties in the range of the Jet A-1 kerosene fuel. These are encouraging preliminary results, inviting further research; coking and sulfur poisoning as well as identification of appropriate reaction conditions are the main challenges to be overcome in the immediate future.

Fluorodenitration of 2-(4-chlorobenzene sulfonyl)-5-nitrotrifluoride using tetramethyl ammonium fluoride affords a mixture of 2-fluoro-5-nitrobenzotrifluoride and two isomers of (4-chlorobenzene sulfonyl)-fluoro-benzotrifluoride.