Characterization of acid-base centres of vermiculite/a-fe2o3 nanoparticles catalyst applied for depolymerization of polystyrene

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61989100%3A27360%2F20%3A10246290" target="_blank" >RIV/61989100:27360/20:10246290 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/61989100:27710/20:10246290

Výsledek na webu

<a href="http://dx.doi.org/10.37904/nanocon.2019.8466" target="_blank" >http://dx.doi.org/10.37904/nanocon.2019.8466</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.37904/nanocon.2019.8466" target="_blank" >10.37904/nanocon.2019.8466</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Characterization of acid-base centres of vermiculite/a-fe2o3 nanoparticles catalyst applied for depolymerization of polystyrene

Popis výsledku v původním jazyce

The acid-base centres on the catalyst surface play important role in catalysis chemistry, influencing protons activity in reaction mechanism. The work presents the characteristics of acid-base centres on the vermiculite/αFe2O3 nanoparticles composites, when used as catalyst for the chemical recycling of polystyrene to styrene. The iron oxides are often used in chemical/petrochemical application as catalyst. The vermiculite is cheap natural clay mineral, which is commonly used as catalyst support. The vermiculite/α-Fe2O3 nanoparticles composites were prepared by precipitation and calcination at 500 and 700 oC. The acid-base centres on the catalyst surface were characterized by TPD (Temperature Programmed Desorption) method allowing to detect the molecules NH3 and CO2 desorbed from the surface when the surface temperature is increased. The temperature of surface and the peak from desorbed molecules suggest the strength of chemical bond between desorbed molecules and surface. Before desorption, the NH3 and CO2 are adsorbed on the surface of catalysts by chemisorption. The TPD method was supplemented with the laboratory analyses using XRD and SEM. It has been found that the vermiculite/α-Fe2O3 nanoparticles composite calcined at 500 oC has medium-strong base centres on the surface, although the pure vermiculite is a light acid and pure α-Fe2O3 is a neutral material. For this reason, it can be successfully applied to the depolymerization reaction in conversion to the styrene monomer. The calcination temperature 700 oC did not improve the basicity, but rather led to its suppression.

Název v anglickém jazyce

Characterization of acid-base centres of vermiculite/a-fe2o3 nanoparticles catalyst applied for depolymerization of polystyrene

Popis výsledku anglicky

The acid-base centres on the catalyst surface play important role in catalysis chemistry, influencing protons activity in reaction mechanism. The work presents the characteristics of acid-base centres on the vermiculite/αFe2O3 nanoparticles composites, when used as catalyst for the chemical recycling of polystyrene to styrene. The iron oxides are often used in chemical/petrochemical application as catalyst. The vermiculite is cheap natural clay mineral, which is commonly used as catalyst support. The vermiculite/α-Fe2O3 nanoparticles composites were prepared by precipitation and calcination at 500 and 700 oC. The acid-base centres on the catalyst surface were characterized by TPD (Temperature Programmed Desorption) method allowing to detect the molecules NH3 and CO2 desorbed from the surface when the surface temperature is increased. The temperature of surface and the peak from desorbed molecules suggest the strength of chemical bond between desorbed molecules and surface. Before desorption, the NH3 and CO2 are adsorbed on the surface of catalysts by chemisorption. The TPD method was supplemented with the laboratory analyses using XRD and SEM. It has been found that the vermiculite/α-Fe2O3 nanoparticles composite calcined at 500 oC has medium-strong base centres on the surface, although the pure vermiculite is a light acid and pure α-Fe2O3 is a neutral material. For this reason, it can be successfully applied to the depolymerization reaction in conversion to the styrene monomer. The calcination temperature 700 oC did not improve the basicity, but rather led to its suppression.

Druh

D - Stať ve sborníku

CEP obor

—

OECD FORD obor

20400 - Chemical engineering

Projekt

Výsledek vznikl pri realizaci vícero projektů. Více informací v záložce Projekty.

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2020

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název statě ve sborníku

NANOCON 2019 : 11th International Conference on Nanomaterials - Research &amp; Application : conference proceedings : peer reviewed : October 16th-18th 2019, Hotel Voronez I, Brno, Czech Republic, EU

ISBN

978-80-87294-95-6

ISSN

2694-930X

e-ISSN

—

Počet stran výsledku

6

Strana od-do

596-601

Název nakladatele

Tanger

Místo vydání

Ostrava

Místo konání akce

Brno

Datum konání akce

16. 10. 2019

Typ akce podle státní příslušnosti

WRD - Celosvětová akce

Kód UT WoS článku

—