PHOSPHATES IN SOL-GEL PREPARATION OF ALUMNA BASED HYDROTREATING CATALYSTS

Sol-gel Preparation of Zirconium Oxide

INTRODUCTION A sol-gel preparation involves f m t the formation of a sol, which is a suspension of solid particles in a liquid, then of a gel, which is a diphasic material with a solid encapsulating a liquid. The liquid can be removed from a gel by either conventional drying (such as by using an oven) to obtain a plojiict kLown as e xercgel, or hy drying with supercritical extraction (often ref...

Catalysts and the structure of SiO2 sol-gel films

In the fabrication of silica films by sol-gel synthesis, the role of various catalysts is systematically examined. The precursor solutions were made by mixing tetraethylorthosilicate (TEOS), ethanol and water in the molar ratio of 1 : 2 : 2. The spin coated films were thermally treated at various temperatures, and characterised using ellipsometry, molecular probe ellipsometry (MPE), infrared sp...

Regeneration of Hydrotreating and FCC Catalysts

Nanostructured hydrotreating catalysts for electrochemical hydrogen evolution.

Progress in catalysis is driven by society's needs. The development of new electrocatalysts to make renewable and clean fuels from abundant and easily accessible resources is among the most challenging and demanding tasks for today's scientists and engineers. The electrochemical splitting of water into hydrogen and oxygen has been known for over 200 years, but in the last decade and motivated b...

Preparation of Silica by Sol-Gel Method Using Formamide

In this work we obtained microporous and mesoporous silica gels by sol-gel processing. Tetraethylortosilicate (TEOS) was used as precursor. Nitric acid and hydrofluoric acid were used as catalysts. In order to study the affect of formamide as drying additive, we used a molar ratio alkoxide/formamide of 1/1. The performance of formamide in obtaining crack-free gels was evaluated through monolith...