Preparing powder useful e.g. to catalyze chemical reaction e.g. hydrogenation reactions and as mineral filler and abrasive article, comprises selecting and determining crystal plane, and hydrothermal synthesis of primary particles

摘要

Process for preparing a powder intended to catalyze a chemical reaction, comprises (a) selecting and determining a crystal plane such as a favorable plane of (1,1,1), (1,1,0) and (1,0,0), where the reaction is sensitive when exposed to the powder, and (b) hydrothermal synthesis of primary particles having a maximum size less than 100 nm and made of more than 99 mass% of dry matter, a constituent of monoclinic structure and process parameters of hydrothermal synthesis adjusted to maximize the percentage of the favorable plane exposed by the particles. An independent claim is included for the powder made for more than 99 mass% of the dry matter of a constituent of monoclinic structure, and consisting for more than 90% of primary particles having a maximum size less than 100 nm, where the primary particles have the form of a stick exposing for more than 35%, of the planes belonging to the family (1,1,1), and/or the form of a plates exposing for more than 35% of the planes belonging to the family (1,0,0), and/or the form of a stick exposing for more than 35% of the planes belonging to the family (1,1,0), in percentages based on the total exposed surface.