Innovative procedure for the preparation of silica fillings without shrinkage

New and innovative aspects

• Method based on sol-gel methodologies, modified to overcome shrinkage and detachment phenomena.
• Use of simple silica precursors which are furthermore common to all supports.
• Use of environmentally sustainable chemicals.
• Extractions with organic solvents are avoided.
• Supports with inner diameters larger than those found in the literature.
• Superior mechanical stability of the prepared filling.

Main advantages of its use

Previous deposition of a thin film allows:

• Avoiding shrinkage, thus reducing the detachment of the monolith provoked by this effect.
• Increasing the adherence of the monolith to the employed support walls.
• Process can be applied to different supporting materials.

Specifications

This new synthetic procedure is based on the incorporation of a porous silica thin film on the walls of the employed supports prior to the synthesis of the filling, with the objective of improving the adhesion of the silica avoiding the shrinkage taking place during the last stages of the sol-gel process.

The development consist on a procedure for the preparation of silica fillings with meso- and/or macroporous structure (hierarchical structure) in the inner volume of different supports made up of different materials and with different inner diameters completely avoiding the shrinkage of the silica, which is divided into the following steps:

1. deposition of a silica thin film on the walls of the support used for filling,
2. preparation of the filling precursor solution with the necessary porogen precursors,
3. synthesis of the silica material which serves as filling in the inner volume of the support.

The employed supports for the filling with hierarchical silica are, a) honeycomb cordierite monoliths, b) glass tubes, c) stainless steel tubing, and d) fused silica capillaries. All the materials present a wide range of compositions (cordierite, glass, fused silica, and steel) and a wide range on internal channel diameter (between 0.25 and 7.28 mm).

Applications

This technological development may be applied in:

• Development of standard or HPLC columns.
• Production of catalytic reactors and microreactors.

Intellectual property status

This technology is protected by the following patent application.

• Title: Procedimiento de preparación de rellenos de sílice que evita el encogimiento de éste mediante depósito previo de una película delgada de sílice
• Priority number: 201400474
• Priority date: 12/06/2014

Current development status

The developed procedure has been tested successfully at laboratory scale with the different aforementioned supports having different diameters, obtaining highly satisfactory results in all cases.

Desired business relationship

The research group seeks companies interested in acquiring this technology for its commercial exploitation through different technology transfer pathways:

• Patent licensing agreements.
• Development of joint R+D Projects for the adaptation of the developed technology to the industry needs.
• Technical cooperation, subcontracting and R+D consultancy.