(14g) Swellable Organically Modified Silica (SOMS): A Novel Support for Pd Catalyzed Hydrodechlorination of Trichloroethylene in Aqueous Phase
AIChE Annual Meeting
Sunday, October 28, 2018 - 5:05pm to 5:20pm
Our studies focus on the application of swellable organically modified silica (SOMS) as a novel catalyst support for HDC of TCE. SOMS belongs to the class of bridged polysilsesquioxanes, which are hybrid organic-inorganic materials, synthesized by sol-gel technique. A unique quality of SOMS is that it swells to almost 3 times itâs dry volume, in presence of organic solvents. Apart from this, properties such as hydrophobicity, mesoporosity, high surface area and absorptivity, also make SOMS an attractive choice for a catalyst support. Furthermore, catalysts involving SOMS as the support were synthesized by impregnation of Pd in its pores. This study aims at investigating the effects of swelling and hydrophobicity of SOMS on the kinetics of HDC of TCE. The deactivation resistance of SOMS towards the anionic species in groundwater is also being studied.
Various techniques such as, near ambient pressure X-ray photoelectron spectroscopy (NAP-XPS), in-situ X-ray absorption near edge structure (XANES), in-situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and laser Raman spectroscopy were used to investigate different characteristics of Pd/SOMS and their role in HDC of TCE. Additionally, techniques such as extended X-ray absorption fine structure (EXAFS), inductively coupled plasma optical emission spectrometry (ICP-OES), transmission electron microcopy (TEM) and mass spectrometry were employed to determine the deactivation resistance of Pd/SOMS. For this study, Pd/Al2O3was used as the basis of comparison. The results indicate that SOMS has great potential to serve as a catalyst support for HDC of TCE.
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