Dehydrogenation of alcohols and hydrogen transfer from alcohols to ketones over hydroxyapatite catalysts

Kibby, Charles L.; Hall, W. Keith

doi:10.1016/0021-9517(73)90271-6

Cited by 120 publications

(28 citation statements)

References 17 publications

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“…In comparison to pristine nanohydroxyapatite (nHA), which strongly catalyses the thermal decomposition of POM by up to 30°C [22], the addition of HA gra ed with PEG (HA-g-PEG) contributed to the signi cant improvement of POM thermal stability, similar to what was observed for HA functionalized with a molar ratio 2 : 2 : 1. HA contains in its structure both acid and basic sites in a single crystal lattice [38][39][40]. In our studies, stoichiometric HA has been applied with molar ratio of Ca/P 1.67.…”

Section: Tg/dtg Studies Of Pom/ha-g-peg Compositesmentioning

confidence: 99%

Thermal Stabilization of Polyoxymethylene by PEG-Functionalized Hydroxyapatite: Examining the Effects of Reduced Formaldehyde Release and Enhanced Bioactivity

Król-Morkisz

Karaś

Majka

et al. 2019

Advances in Polymer Technology

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Nanostructured hydroxyapatite (HA) functionalized with poly(ethylene glycol) (HA-g-PEG) of different molar mass was used as a thermal stabilizer to prepare polyoxymethylene (POM) composites by a melt processing method. The chemical and crystalline structure of (HA-g-PEG) and POM/HA-g-PEG composites was investigated by means of FTIR and XRD. The thermal properties, degree of crystallinity, and melting behaviour of POM-based composites were analysed with TG, DSC, and TOPEM DSC methods. The tensile strength, Young’s modulus, toughness, and wettability of POM were investigated as well. A preliminary assessment of bioactivity, in vitro chemical stability, and formaldehyde release from POM/HA-g-PEG composites by Schiff’s test was also performed. An SEM/EDX method was used to observe the morphology of POM/HA-g-PEG composites. The results indicate that the addition of 1% HA-g-PEG slightly increases the melting temperature and degree of crystallinity. In small amounts, HA-g-PEG particles probably act as nucleating agents for the POM crystallization process. Incorporation of 5% HA-g-PEG to POM caused a decrease in the crystallinity of the polymer matrix, as a result, some mechanical properties of POM/HA-g-PEG composites also decreased. The thermal stability of POM/HA-g-PEG composites improved significantly from 309°C for unmodified POM to 342°C for POM/10.0% HA-g-PEG 600. The most effective thermal stabilizer was synthesized with the lowest mass-average molar mass PEG. The in vitro bioactivity test confirmed that, as the average molar mass of PEG in HA-g-PEG hybrids increased, POM-based composites indicated higher bioactivity. The in vitro chemical stability analysis results showed that both the POM matrix and the HA-g-PEG additive remain stable during the whole incubation time. Importantly, after seven days of dynamic incubation, no formaldehyde was detected in all filtrates, which is crucial in biomedical applications, among others.

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Section: Tg/dtg Studies Of Pom/ha-g-peg Compositesmentioning

confidence: 99%

Thermal Stabilization of Polyoxymethylene by PEG-Functionalized Hydroxyapatite: Examining the Effects of Reduced Formaldehyde Release and Enhanced Bioactivity

Król-Morkisz

Karaś

Majka

et al. 2019

Advances in Polymer Technology

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“…This yields a family of compounds with very different properties, from more acidic solids in the case of decient HAPs (x > 0) to solids more and more basic when approaching the stoichiometry of the native HAP (x ¼ 0), this latter being, therefore, predominantly basic. 2,9,10 The Ca/P ratio is commonly used as an index of their non-stoichiometry (the stoichiometric ratio being 1.67) and of their acid-base behaviour. It is well known that HAPs act as solid acid catalysts when Ca/P z 1.50, and develop both the acidic and the basic characteristics when the Ca/P ratio is between 1.50 and 1.67.…”

Section: Introductionmentioning

confidence: 99%

Structural, textural and acid–base properties of carbonate-containing hydroxyapatites

et al. 2014

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“…Moreover, the reaction was widely studied and numerous kinetic equations were established for the reaction. Its mechanism possibly changes with the increase of temperature, suggesting that instabilities might arise from the coupling of the reaction kinetics and the experimental conditions [22,23].…”

Section: Introductionmentioning

confidence: 98%

Surface reactivity and self-oscillating oxidation of butan-2-ol over palladium loaded AlPO4

Ouariach

Kacimi

Ziyad

2015

Applied Catalysis A: General

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Dehydrogenation of alcohols and hydrogen transfer from alcohols to ketones over hydroxyapatite catalysts

Cited by 120 publications

References 17 publications

Thermal Stabilization of Polyoxymethylene by PEG-Functionalized Hydroxyapatite: Examining the Effects of Reduced Formaldehyde Release and Enhanced Bioactivity

Thermal Stabilization of Polyoxymethylene by PEG-Functionalized Hydroxyapatite: Examining the Effects of Reduced Formaldehyde Release and Enhanced Bioactivity

Structural, textural and acid–base properties of carbonate-containing hydroxyapatites

Surface reactivity and self-oscillating oxidation of butan-2-ol over palladium loaded AlPO4

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