Aerogel palladium

These porous solids obviously have very high surface areas, and they lend themselves naturally to service in catalysis. Palladium catalysts supported on alumina aerogels have been used successfully to remove CO and NO from automobile exhausts,13 and a V205/Ti02 aerogel is itself a catalyst for the selective reduction of NO to N2 and water by gaseous ammonia.14... 

Apart from these examples, nanoparticle-containing ionic liquids can also be used to impregnate a solid support from which the liquid is finally removed.1831 A solution of palladium colloids in [C4Ciim][Tf2N] was added to an orthosilicate and allowed to gelate. Afterwards, the ionic liquid was extracted with acetonitrile and the resulting aerogel used to reduce cinna-maldehyde. 

Fig. 15 In situ formation of supported palladium particles on Ca-alginate aerogels...

CATALYTIC OXIDATION OF PROPANE OVER PALLADIUM SUPPORTED ON ALUMINA AEROGEL. EFFECTS OF THE PRETREATMENT ON THE ACTIVITY AND INVESTIGATION OF THE STATE OF PALLADIUM BY GRAZING-INCIDENCE-X-RAY DIFFRACTION... 

Scheme 5.6-10 2,4-hydrogenation of cinnamaldehyde using aerogel-supported ionic liquid catalyst material containing palladium nanoparticles [112]. 

The deposition of metals has been observed in a number of catalytic processes in ionic liquids and this will be discussed in Section 6.3. This has encouraged the exploration of the possibility of the chemical deposition of metals from solutions in ionic liquids. For instance, lr(0) nanoparticles 2.3 0.4 run in diameter have been prepared by the reduction of [Ir(cod)Q]2 in [BMIMjfPFs] with H2 [24]. In a particularly elegant experiment, palladium nanoparticles were first formed by the thermal decomposition of paUadium(ii) acetate in the presence of triphenylphosphine (to give a regular particle size of 1 run) in [BMIM][Tf2N]. A silica aerogel support was then formed around the nanoparticles by adding (EtO)4Si and formic acid to the mixture [25],... 

Successively, carbon aerogels doped palladium nanoparticles as a recoverable catalyst was applied in the hydroxycarbonylation of aryl iodides by Cacchi and colleagues [144]. Using DMF as a solvent at 100 °C with acetic anhydride/lithium formate along with lithium chloride and DiPEA (MA-dusopropylethylamine) as a base, high to excellent yields can be achieved. The catalyst can be reused up to 12 times without any appreciable loss of activity in the case study of p-iodotoluene. 

Bali S, Turpin GC, Ernst RD, Pugmire RJ,. Singh V, Seehra MS, Eyring EM (2008) Water gas shift catalysis using iron aerogels doped with palladium by the gas-phase incorporation method, linergy Fuels 22 1439-1443. 

Martinez S, Moreno-Manas M, VallriberaA, Schubert U, Roig A, Molins E (2006) Highly dispersed nickel and palladium nanoparticle silica aerogels sol-gel processing of tethered metal complexes and application as catalysts in the Mizoroki-Heck reactim. New J Chan 30 1093-1097... 

Morley KS, Licence P, Marr PC, Hyde IR, Brown PD, Mokaya R, Xia YD, Howdle SM (2(X)4) Supercritical fluids A route to palladium-aerogel nanocranposites. J Mater Chem 14 1212-1217... 

Soler R, Cacchi S, Fabrizi Get al (2007) Sonogashira Cross-Coupling Using Carbon Aerogel Doped with Palladium Nanoparticles A Recoverable and Reusable Catalyst. Synthesis 19 3068-3072 Du H, Li B, Kang Fet al (2007) Carbon aerogel supported Pt-Ru catalysts for using as the anode of direct methanol fuel cells. Carbon 45 429-435... 

Preparation of single and binary inorganic oxide aerogels and their use as supports for automotive palladium catalysts... 

In this paper, we describe methods for the preparation of single or binary inorganic oxide aerogels that could be used as carriers for high performance supported Pd automotive catalysts. Indeed we have shown that alumina - based aerogel supported palladium catalysts were very active in propane oxidation [2]. Here we present the catalytic performances, in the reaction CO + NO -1- O2, of palladium catalysts supported on some of the prepared aerogels and compare their performances with those of Pd or Pt-Rh catalysts supported on a commercial alumina. 

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