Synthesis of SiO2 xerogels and Pd/SiO2 cogelled xerogel catalysts from silylated acetylacetonate ligand

Iron(III) species dispersed in porous silica through sol–gel chemistry

“…In the range of mesopores and macropores, Fe/ SiO 2 -C(M) and Fe/SiO 2 -C(E) exhibit a continuous diameter distribution from a few nm to a few lm and their total porous volumes of 3.3 ± 0.1 and 3.1 ± 0.1 cm 3 /g, see Table 1, are of the order of magnitude of those obtained with aerogels dried under supercritical conditions [7,33]. It has been shown in previous studies that this texture is typical of cogelled catalysts [7,9,34,35]. The bulk densities, q bulk , obtained from mercury pycnometry, confirm the differences observed in the total porous volumes.…”

Synthesis and characterization of sol–gel zirconia supported Pd and Ni catalysts

“…Numerous authors have shown the ability to disperse catalytic metals on gels whose texture is finely controlled by the sol-gel route [10]. The intimate mixing at the molecular level of different components obtained at the end of reactions is probably the main reason for using sol-gel methods [11]. Cogellation in which the metal is introduced into the initial solution in the form of a salt and impregnation, usually incipient wetness of xerogels supports are mostly used.…”

Characterization of low-density silica xerogel formed into microspheres

“…These catalysts are prepared by co-gelation of TEOS and EDAS after complexation of the corresponding metal precursor, Pd(acac) 2 and Ag(OAc), by the ligand EDAS [17]. This one-step sol-gel synthesis leads to nanometer-sized metal particles located in the center of the silica particles completely accessible through the particle microporosity [11][12][13][14][15][16][17]. This is the reason why the microporosity preservation is a major concern for catalyst beads to ensure the maintenance of catalytic performance observed for the reference catalyst material.…”

“…The use of alkoxides bearing both nucleating groups and a group able to complex an active metal, such as in 3-(2-aminoethylamino)propyltrimethoxysilane (EDAS) makes it possible intentionally to position metallic species (e.g. Pd, Ag, Cu) inside microporous silica particles, where they are dispersed at a nanometric level, accessible for reaction and sinterproof [11][12][13][14][15][16][17].…”