5 research outputs found
Synergistic Factors Affecting Catalytic Performance of Fe(II) Phthalocyanine @ Titania-Pillared Bentonite Nanocomposites in Styrene Production
The hybrid nanocatalytic system under study consisted of iron (II) phthalocyanine complex (FePc) of 0.5 – ~10 wt % loading immobilized in the bentonite interlayers modified by pillaring with titania nanoparticles (88 nm). Various interactions facing FePc complex were discussed through the changes in different characteristics assessed by adopting XRD, FTIR, ICP-EDX, TGA-DrTGA, TEM, N2 adsorption-desorption and H2-chemisorption techniques. Intercalated FePc molecules could evolve excessive silanol and aluminol sites through interaction with various clay-interlayer sites and titania pillar. By applying this FePc @ Ti-PILB nanocomposite in oxidative dehydrogenation of ethyl benzene, synergistic combination of factors influencing selective production of styrene confirmed the optimum turnover frequency with maximum selectivity to styrene at 3.4 wt % FePc loading. Below this loading, redox pair factor linked with dispersion and orientation mode of FePc was predominating. In higher loaded samples of considerable silanol sites, clay acid-base pair balance became prevailing
Iron oxychloride as an efficient catalyst for selective hydroxylation of benzene to phenol
Selective hydroxylation
of benzene is a felicitous strategy for
the production of phenol that is deemed to be an alternative to conventional
processes. Thus, the development of a durable and highly efficient
catalyst for the selective hydroxylation of benzene should be a key
topic. In this work, FeOCl was prepared by a chemical vapor transition
method and characterized using various techniques including XRD, TEM,
Raman spectroscopy, N2 adsorption–desorption, DLS,
and TGA. The prepared FeOCl was applied as a heterogeneous catalyst
in benzene hydroxylation, and the reaction conditions were optimized.
The acquired data manifested that FeOCl has shown superiority over
the other reported catalysts utilized in benzene hydroxylation. The
superiority of FeOCl is attributed to the facile self-redox potential
of FeOCl and its remarkable ability for the production of an overwhelming
amount of hydroxyl radicals in a short period of time. The catalyst
recovery and reuse test showed that FeOCl is able to endure the harsh
conditions of benzene hydroxylation for four runs. The mechanism of
benzene hydroxylation using FeOCl as a catalyst in the presence of
hydrogen peroxide as an oxidant was also illustrated
A Supported Nickel Phthalocyanine Complex as a Selective Catalyst for the Production of Styrene
A nickel phthalocyanine complex (NiPc) supported on bentonite clay (Bihar, India) was used as a selective catalyst for the dehydrogenation of ethylbenzene to styrene. Maximum activity was observed for the catalyst sample containing 1.0 wt% NiPc/bentonite. A higher loading of complex (> 1.4 wt%) exhibited no activity and resembled polycrystalline NiPc. The texture of the studied catalyst and the mode of surface dispersion of the supported NiPc were investigated through the adsorption of N 2 and O 2 , respectively. The activity of the diluted samples could be attributed to the presence of separate highly dispersed molecules of NiPc on the bentonite surface without having a marked effect on its pore system for most active samples. The selectivity towards styrene was found to depend strongly on the NiPc surface area and the degree of dispersion. The activity was a function of the whole structure including modifications of both acid sites through different interactions and of the pore system through a penetration mechanism
Glycolysis of Poly(ethylene terephthalate) Catalyzed by the Lewis Base Ionic Liquid [Bmim][OAc]
The glycolysis of polyÂ(ethylene terephthalate)
(PET) was studied
using 1-butyl-3-methylimidazolium acetate ([Bmim]Â[OAc]) as a catalyst.
The effects of temperature, time, ethylene glycol dosage, PET amount,
and [Bmim]Â[OAc] dosage on the glycolysis reaction were examined. The
results revealed that [Bmim]Â[OAc] has a PET conversion of 100% and
a bisÂ(2-hydroxyethyl)Âterephthalate (BHET) yield of 58.2% under the
optimum conditions of 1.0 g of [Bmim]Â[OAc] with 20 g of ethylene glycol
in the presence of 3.0 g of PET at 190 °C after 3 h of glycolysis.
The ionic liquid could be reused up to six times with no apparent
decrease in the conversion of PET or yield of BHET. The pH plays a
major role in explaining the proposed mechanism of glycolysis using
the Lewis base ionic liquid [Bmim]Â[OAc]. The kinetics of the reaction
was first-order with an activation energy of 58.53 kJ/mol