Physicochemical properties of some metal supports for hydrotreating catalysts preparation

Surface Area, Pore Volume Distribution, and Acidity in Mesoporous Expanded Clay Catalysts from Hybrid Density Functional Theory (DFT) and Adsorption Microcalorimetry Methods

“…Steam aging has similar effects on zeolite containing fluid cracking catalysts . Acidity and porosimetry data of reference silicas and silicate powders is given elsewhere 9 Differential heat profiles for the different saponite catalysts.…”

“…From the petroleum engineer's viewpoint, acidic mesostructures of the MCM-41 type suffer from two major limitations, namely, high coke generation and lack of hydrothermal stability. In fact, although they have excellent thermal stability in air to 800 °C, when exposed to 100% steam at 1 atm for 5 h, a typical MCM-41 undergoes a total structural collapse at T > 600 °C; stability to 20% steam at 600−800 °C has recently been reported. , At microactivity test (MAT) conditions prior to steam aging, MCM-41 type crystals have gas−oil cracking activity (70−75% conversion) comparable to that of an equilibrium FCC …”

Acidity of the silica–alumina/BX3superacids

“…Silica-alumina with high SiO 2 content is a solid acid of moderate strength. 6 In our study we used silica-alumina containing 87% of SiO 2 whose acid centres catalyse neither pentane nor 3methylpentane isomerization at room temperature but merely that of toluene with 2-chloro-2-methylpropane and 2-chlorobutane alkylation (Table 1). The reaction with BCl 3 vapour converted it into a superacid 2 able to catalyse n-pentane isomerization at room temperature (Table 2).…”

Micro- and mesoporous silicas synthesized in acidic water–ethanol solution of equimolar catanionic surfactant

“…Among others, the synthesis of a material with micro-and mesoporous properties is a promising strategy for endowing them with a specific functionality, because molecules are first transported through mesopore channels and then strongly adsorbed in the micropores [2,3]. Although some silica-alumina gels have micro-and mesoporosity, the microporosity of those gels contains no more than 5% of total pore volume and the mesopores are widely distributed in the range of 2-10 nm [4]. Pinnavaia synthesized porous lamellar silica with micro-and mesoporosity using C12 diamine surfactant [5].…”