Fluoride-Treated Nano-HZSM-5 Zeolite as a Highly Stable Catalyst for the Conversion of Bioethanol to Propylene.

Fluoride treatment of ZSM-5 zeolite can effectively adjust surface acidity and generate a secondary pore structure. In this study, a series of modified nano-HZSM-5 zeolites were prepared by NHF-HF mixed solution treatment and applied to the selective conversion of bioethanol to propylene at 500 °C, atmospheric pressure, and a WHSV of 10 h. The results showed that NHF-HF modification weakened the surface acidity of nano-HZSM-5 zeolites, thus inhibiting coke formation.

Enhanced Proximity of Rh-Rh Ensembles Encaged in UiO-67 Boosting Catalytic Conversion of Syngas to Oxygenates.

Maintaining high conversion under the premise of high oxygenates selectivity in syngas conversion is important but a formidable challenge in Rh catalysis. Monometallic Rh catalysts provide poor oxygenate conversion efficiency, and efforts have been focused on constructing adjacent polymetallic sites; however, the one-pass yields of C oxygenates over the reported Rh-based catalysts were mostly <20 %. In this study, we constructed a monometallic Rh catalyst encapsulated in UiO-67 (Rh/UiO-67) with enhanced proximity to dual-site Rh-Rh ensembles.

Determination of total phenol and six polyphenolic components in the polyphenol extract of by quantitative nuclear magnetic resonance spectroscopy.

A quantitative nuclear magnetic resonance spectroscopy (qNMR) method was established for determining the total phenol and six polyphenolic components in the polyphenol extract of . The qNMR approach utilized DMSO-d as the deuterated solvent and potassium hydrogen phthalate as the internal standard for quantifying the total phenolic content, expressed as epicatechin equivalence in the sample. Two complementary qNMR methods with DMSO-d or DO as solvent were established to simultaneously determine 6 polyphenol components in the cinnamon polyphenol extract, including epigallocatechin gallate (EGCG), epicatechingallate (ECG), epicatechin (EC), epigallocatechin (EGC), gallocatechin gallate (GCG) and gallic acid (GA).