Catalytic and physical characteristics of axially modified cobalt (III) tetraphenyl porphyrin immobilized on chemically different supports

Hassan, Salah A.; Hassan, Hamdy A.; Hashem, Khaled M.; Dayem, H.M. Abdel

doi:10.1016/j.apcata.2005.10.036

Cited by 18 publications

(9 citation statements)

References 41 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…), respectively. This indicates that the specific activity decreases with the packing of oriented complex molecules on the clay surface, confirming probably that the operating active sites involve isolated separate complex species [5,9]. It is to be mentioned here that the extent of immobilized CoPc on the bentonite surface in the present study did not reach the monolayer coverage of the support (for a ¼ 1.0, the CoPc loading should be 7.7 wt%).…”

Section: Catalytic Activity In the Polymerization Process As A Functimentioning

confidence: 54%

“…Among the studied complexes, metal phthalocyanines (resembling the natural porphyrins structurally) have become known to catalyze many reactions both in liquid and gas phases [e.g., [5][6][7][8][9][10]. Immobilization of such complexes on a suitable solid matrix was considered as one of the promising approaches for their stabilization against dimerization and other destructive processes [1,[10][11][12].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Catalytic Behavior of Cobalt (II) Phthalocyanine Immobilized on Bentonite Clay in Bulk Polymerization of Methyl Methacrylate

Sadek

Solyman

Abdel‐Samad

et al. 2010

International Journal of Polymeric Materials

Self Cite

View full text Add to dashboard Cite

The catalytic behavior of cobalt (II) phthalocyanine (CoPc) immobilized on bentonite clay, with different complex loadings ranging between 0.2 and 2.2 wt%, in the presence of n-butyl amine solvent, was investigated in bulk polymerization of methyl methacrylate without using an activator or cocatalyst. The interaction of CoPc molecules with a bentonite surface, encouraged by the amine, involved the inclined stacking model, i.e., interaction between N-atoms of the macro-ring system and OH's of the support. Two different mechanistic pathway regions could be suggested, depending on complex loadings. The first was in the range, 0.2À1.0 wt% CoPc, behaving in ionic fashion as the bare bentonite. Isolated oriented molecules probably activated bentonite through the exposure of new internal acid sites during intercalation. The second, in the range of 1.4À2.2 wt% CoPc, proceeded via combined mechanisms, ionic functioned by bentonite support and free radical functioned by complex packed oriented stacks, staggered in clay galleries to cover a fraction of internal active acid sites. The number of polymer chains formed per one CoPc center (reaction turnovers) was >2-$10 with diluted catalyst samples. With higher loadings, one chain was formed per active site. Such behaviors, without a detectable effect on polymer characteristics or enchainment sequence, were studied in light of intercalation, orientation and accessibility models.

show abstract

Section: Catalytic Activity In the Polymerization Process As A Functimentioning

confidence: 54%

Section: Introductionmentioning

confidence: 99%

Catalytic Behavior of Cobalt (II) Phthalocyanine Immobilized on Bentonite Clay in Bulk Polymerization of Methyl Methacrylate

Sadek

Solyman

Abdel‐Samad

et al. 2010

International Journal of Polymeric Materials

Self Cite

View full text Add to dashboard Cite

show abstract

“…In micrograph (c) of the sample of coat 1 (6Mo-8 V=T), the incorporated molybdena could lead to fewer patches of dissociated particles (of <20 nm), as compared with the co-impregnated sample (cf., micrograph, b). It can be evident that, beside the physical entrance of some vanadia species in the titania mesoporous system, a fraction of these nano species can be coordinatively bonded with some interior sites [31,34]. For the sample of coat 2 (8 V-6Mo=T), micrograph (d) shows more dense particles in a larger number of patches, where mobile vanadia seems to lie almost on the top surfaces of titania or molybdena.…”

Section: Textural and Morphological Characteristics Of Investigated Smentioning

confidence: 93%

Various Characteristics of Nanosized V₂O₅/TiO₂and MoO₃–Modified V₂O₅/TiO₂Catalytic Systems Used in Redox-Initiated Polymerization of Methyl Methacrylate

Hassan

Sadek

Hassan

et al. 2011

International Journal of Polymeric Materials

Self Cite

View full text Add to dashboard Cite

Various samples of nanosized V 2 O 5 (2-20 wt%)=TiO 2 catalytic systems (of particle sizes ranged between 5 and 50 nm were characterized. The effect of addition of MoO 3 (3-9 wt%), in different sequences, was followed up in view of competing interactions with titania surface. Characterization was performed through XRD, FTIR, BET, and TEM techniques. Catalytic activity of prepared samples was tested in redox-initiated polymerization of methyl methacrylate, in presence of NaHSO 3 cocatalyst. The proposed polymerization mechanism indicated participation of HSO Á 3 radicals, primarily generated on a TiO 2 surface, with V 5þ =V 4þ and=or Mo 6þ =Mo 5þ redox pairs to form active radical species with the monomer. In all cases, extremely high yields of reasonably high molecular weight polymers, of syndiotactic-structure, were functions of catalyst nanosized nature, rapid redox-initiation steps, and mode of MoO 3 addition.Keywords MoO 3 -modified V 2 O 5 =TiO 2 , redox-initiated polymerization, methyl methacrylate, V 2 O 5 =TiO 2

show abstract

“…In this respect, Co@AA-co-AM-80 shows a higher MB degradation rate constant than Cu@AA-co-AM-80 inferring the accessibility of the cobalt redox pairs to decompose H 2 O 2 molecules better than the copper redox pairs [43,44].…”

Section: Degradation Kinetic Studies Of Methylene Blue Dyementioning

confidence: 95%

Elaboration of metal (M: Co, Cu, Ni, Fe) embedded poly(acrylic acid-co-acrylamide) hydrogel nanocomposites: An attempt to synthesize uncommon architectured “Auto-active” nanocatalysts for treatment of dyeing wastewater

Mekewi

Darwish

2015

Materials Research Bulletin

View full text Add to dashboard Cite

Catalytic and physical characteristics of axially modified cobalt (III) tetraphenyl porphyrin immobilized on chemically different supports

Cited by 18 publications

References 41 publications

Catalytic Behavior of Cobalt (II) Phthalocyanine Immobilized on Bentonite Clay in Bulk Polymerization of Methyl Methacrylate

Catalytic Behavior of Cobalt (II) Phthalocyanine Immobilized on Bentonite Clay in Bulk Polymerization of Methyl Methacrylate

Various Characteristics of Nanosized V₂O₅/TiO₂and MoO₃–Modified V₂O₅/TiO₂Catalytic Systems Used in Redox-Initiated Polymerization of Methyl Methacrylate

Elaboration of metal (M: Co, Cu, Ni, Fe) embedded poly(acrylic acid-co-acrylamide) hydrogel nanocomposites: An attempt to synthesize uncommon architectured “Auto-active” nanocatalysts for treatment of dyeing wastewater

Contact Info

Product

Resources

About

Catalytic and physical characteristics of axially modified cobalt (III) tetraphenyl porphyrin immobilized on chemically different supports

Cited by 18 publications

References 41 publications

Catalytic Behavior of Cobalt (II) Phthalocyanine Immobilized on Bentonite Clay in Bulk Polymerization of Methyl Methacrylate

Catalytic Behavior of Cobalt (II) Phthalocyanine Immobilized on Bentonite Clay in Bulk Polymerization of Methyl Methacrylate

Various Characteristics of Nanosized V2O5/TiO2and MoO3–Modified V2O5/TiO2Catalytic Systems Used in Redox-Initiated Polymerization of Methyl Methacrylate

Elaboration of metal (M: Co, Cu, Ni, Fe) embedded poly(acrylic acid-co-acrylamide) hydrogel nanocomposites: An attempt to synthesize uncommon architectured “Auto-active” nanocatalysts for treatment of dyeing wastewater

Contact Info

Product

Resources

About

Various Characteristics of Nanosized V₂O₅/TiO₂and MoO₃–Modified V₂O₅/TiO₂Catalytic Systems Used in Redox-Initiated Polymerization of Methyl Methacrylate