Towards in Situ Temperature Detection at the Single-Particle Level on Supported Olefin Polymerization Catalysts

Abstract

Temperature plays a major role in catalysis due to its inherent relation with chemical selectivity and reaction speed. In this context, we study the heat generated during an exothermic polymerization reaction on silica supported ole n polymerization catalysts. To achieve this, core-shell nanoparticles that display temperature-dependent luminescence were synthesized and deposited on ole n polymerization catalysts by solution impregnation. SEM(-EDX) showed a near homogeneous distribution of the nanoparticles over the catalyst particles. Activity measurements showed no signi cant deactivation of the catalyst at 1 wt% weight loading of nanoparticles. For selected ole n polymerization catalysts, a temperature increase of∼12 K was observed at room temperature and 1 bar ethylene. Moreover, ex situ confocal microscopy measurements allowed temperature mapping with high spatial (µm-scale) and temporal resolutions with a maximum temperature uncertainty of 3.5 K. This is an important step towards in situ temperature detection on the single catalyst particle level during ethylene polymerization.