Alumina support, a process for preparing the support, a silver catalyst prepared from the support, and use thereof

A process for preparing an alumina support, comprising:

• (a) mixing at least one alumina starting material, at least one alkaline earth metal salt, optionally at least one carbonaceous burnout material, optionally at least one fluoride, at least one binder and water to produce a mixture,
• wherein the alumina starting material comprises alpha-alumina trihydrate and pseudo-boehmite in a weight ratio of alpha-alumina trihydrate to pseudo-boehmite ranging from 0,5:1 to 5:1, and
• wherein based on the total weight of the alumina starting material,
• the alkaline earth metal salt is in an amount ranging from 0.05% to 3.0% by weight, calculated based on the alkaline earth metal,
• the carbonaceous burnout material is in an amount ranging from 0% to 30% by weight,
• the fluoride is in an amount ranging from 0% to 3% by weight, and
• the binder and water are in a total amount ranging from 10% to 40% by weight;
• (b) extruding the mixture obtained in step (a) to form shaped entities;
• (c) drying the shaped entities obtained in step (b) at a temperature ranging from 60° C. to 200° C.;
• (d) calcining the shaped entities obtained in step (c) at a temperature ranging from 1100° C. to 1600° C. to convert to a semi-finished alpha-alumina support;
• (e) treating the semi-finished alpha-alumina support obtained in step (d) with a thermally decomposable organic acid solution having a pH of no more than 2.5;
• (f) washing the treated support obtained in step (e) with water to produce a leach liquor having a pH of more than 5 and a water-washed product:
• and
• (g) heat-treating the water-washed product obtained in step (f) at a temperature ranging from 80° C. to 1200° C.