Nano-ceria–zirconia promoter effects on enhanced coke combustion and oxidation of CO formed in regeneration of silica–alumina coked during cracking of triisopropylbenzene

Enhanced triisopropylbenzene cracking and suppressed coking on tailored composite of Y-zeolite/amorphous silica–alumina catalyst

“…The activity of the catalysts for TIPB cracking decreases with the same pace as TOS. During the cracking, the catalyst surface is covered with layers of coke deposit; thereby the accessible surface area decreases, active sites are coated with the deposits of coke and pores are blocked with the coke buildup [27]. At lower times on stream, all the samples are deactivated very fast via coking, indicating that the large portion of the coke is formed at the early stage of the TIPB cracking experiments.…”

“…In order to follow the changes in the number of acid sites of different strengths, the TPD profiles were deconvoluted using Gaussian deconvolution method to provide three sub-profiles (not shown here), representing weak, medium and strong acid sites. The sub-profiles with the peak positions at 150-250, 270-430, and above 450 ˚C were respectively assigned to weak, medium, and strong acid sites [27]. The amount and strength of acid sites of the samples, with a confidence level of 94%, are summarized in Table 2.…”

Oxidation of benzene over bimetallic Cu–Ce incorporated rice husk silica catalysts

“…A mixture of micropores and mesopores can be formed when cerium ion concentration is very low. Thus an irregularity suggests the co-existence of pores with different sizes probably by insertion of loaded metal ions [29]. In RHA-10Cu20Ce, pore-size distribution shows only mesopores with an average diameter of ∼12.6 nm which decreases to ∼9.6 nm upon increasing cerium content in RHA-10Cu50Ce.…”

A new route for the synthesis of self-acidified and granulated mesoporous alumina catalyst with superior Lewis acidity and its application in cumene conversion

“…The figure shows that mesoporous c-alumina holds 3 types of acid groups, corresponding to 3 peaks of different intensities, surface areas, and temperature range for ammonia desorption. Weak, medium, and strong acid sites are identified in the temperature ranges: 120-250°C, 250-430°C, and from 430 to 500°C (and above), respectively [52]. Table 1 reports the results of peak area calculations for the two materials.…”