Method for preparing alumina supporter with high specific surface area

Abstract

The invention discloses a method for preparing an alumina supporter with high specific surface area. The method comprises the following steps of (1) weighing a certain amount of pseudoboehmite dry glue power, a certain amount of physical pore-enlarging agent and a certain amount of extrusion assistant agent to be evenly mixed and then adding an aqueous solution containing a chemical pore-enlarging agent; (2) evenly mixing materials obtained in the step (1) and extruding a mixture into strips; and (3) drying the material obtained the step (2), and calcinating a dried material in the nitrogen atmosphere to calcinate and prepare the alumina supporter in the air atmosphere. The alumina supporter prepared by means of the preparation method is large in pore volume and specific surface area, concentrated in pore distribution and moderate in mechanical strength, can be suitable for the fields of petroleum processing, chemical engineering, environmental protection and the like, and is especially suitable for preparation of heavy oil hydrotreating catalysts and residual oil hydrotreating catalysts.

Description

technical field [0001] The invention relates to a preparation method of alumina carrier. Background technique [0002] At present, in the production process of hydrodemetallization of heavy oil and residual oil, because the raw oil contains a certain amount of impurities such as vanadium, sulfur, arsenic, nickel, etc., deposits are easily formed, thereby blocking the pores of the catalyst, resulting in a rapid decline in catalyst activity. , resulting in inactivation and affecting industrial applications. The physical properties of the catalyst support, such as the programmable pore size, pore size distribution, mechanical strength, specific surface area, pore volume, etc., are important factors affecting the activity and stability of the hydrodemetallization catalyst. Alumina is a commonly used catalyst carrier, widely used in petroleum processing, chemical industry, environmental protection and other fields. The alumina and commercially available alumina usually used to ...

AI Technical Summary

Problems solved by technology

The existing technology has such shortcomings: the physical pore-enlarging agent first oxidizes and transforms into gas at a relatively low temperature (about 600°C) during the high-temperature calcination process of the carrier and releases the space originally occupied, while the carrier needs to be Roasting at a higher temperature (about 800°C) for 2 to 4 hours, during which pseudo-boehmite undergoes dehydration and crystal transformation to form alumina

Therefore, during high temperature calcination, it is easy to cause the space released by the oxidation of the physical pore expander to collapse and sinter, thereby reducing the pore volume and specific surface area of ​​the carrier, widening the pore distribution, and deteriorating the mechanical strength.