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

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 poly­(ethylene terephthalate) (PET) was studied using 1-butyl-3-methylimidazolium acetate ([Bmim]­[OAc]) as a catalyst. The effects of temperature, time, ethylene glycol dosage, PET amount, and [Bmim]­[OAc] dosage on the glycolysis reaction were examined. The results revealed that [Bmim]­[OAc] has a PET conversion of 100% and a bis­(2-hydroxyethyl)­terephthalate (BHET) yield of 58.2% under the optimum conditions of 1.0 g of [Bmim]­[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]­[OAc]. The kinetics of the reaction was first-order with an activation energy of 58.53 kJ/mol