Dispersion of Nano Nickel Particles over SBA-15 Modified by Carbon Films on Pore Walls

Abstract

Mesoporous SBA-15 was prepared by using P123 as a template. The precursor with the template was calcined in an inert atmosphere so that carbon films might be formed in pores of SBA-15 due to the decomposition of template. The SBA-15C thus formed contained 3% C and exhibited similar pore structures as the SBA-15. Both SBA-15 and SBA-15C were used to support 20% nickel (by weight) via impregnation. It was found that doping with carbon films enhanced the dispersion of supported nickel. However, calcination at high temperatures before the reduction had a negative effect on the dispersion of nickel. The un-calcined 20%Ni/SBA-15C after the reduction in H 2 at 673 K exhibited the highest dispersion of nickel (42%) and smallest average particle size of about 2.4 nm, in the catalysts studied in this work. It was also the most active catalyst for the hydrogenation of toluene to methyl cyclohexane. Conversion of toluene could be detected even at room temperature and atmospheric pressure for the catalyst in a fix-bed reactor, and 100% conversion of toluene was reached when temperature was raised to 358 K.

Catalytic steam reforming of tar derived from steam gasification of sunflower stalk over ethylene glycol assisting prepared Ni/MCM-41

“…They found that the coke is difficult to be formed on its surface and metal sintering rate is also slow. Nickel metal sometimes showed the similar catalytic activity as some noble metals such as Pt and Pd [17,24]. Rh is found to have higher catalytic performance and coke resistant ability than Ni in the steam reforming of tar, but it is limited by its high cost for large-scale applications [25].…”

“…In general, the support materials with low surface area (mostly less than 200 m 2 /g) easily lead to the sintering of supported metal during the thermal treatment period due to low dispersion with high accumulation of metal [31]. Recently, mesoporous molecular sieves such as HMS, KIT-1, SBA-15 and MCM-41 with high BET surface area have been attracted considerable interest as catalyst supports [24,32]. Among them, MCM-41 is widely utilized 5 as adsorbents, catalyst support and hydrogenation catalyst.…”

Preparation of Fe2P/Al2O3 and FeP/Al2O3 catalysts for the hydrotreating reactions

“…Due to the strong interactions of iron species with Al 2 O 3 , it would be easy to prepare the catalyst with highly dispersed iron species. In addition, a small amount of carbon was added into the Fe/Al 2 O 3 in order to promote the reduction of supported iron species [16] . Then, the…”

Experimental Study of Silver-Loaded Mesoporous Silica for the Separation of Ethylene and Ethane

“…The low adsorption capacity was another drawback for this type of adsorbents. Among the commercial adsorbents involving π-complexation mechanism, such as activated carbon, − Y molecular sieve, 13X molecular sieve and 4A molecular sieve, , carbon molecular sieve , and silica gel, mesoporous silica materials appears to be the promising candidates for olefins and paraffins separation due to its features of large specific surface areas, narrow pore size distribution, adaptable pore size, and facile functionalization. − As an example, mesoporous adsorbent Ag-MCM-41 was successfully applied to the separation of propane and propylene by forming CC complexation with olefins …”