Diatomite porous structure

Many of the materials currently under development draw their inspiration from structures found in nature. That is, by mimicking the supramolecular architecture of natural materials, one can prepare complex materials capable of highly sophisticated functions. An important aspect of this work involves the selection of microorganism templates (e.g., diatomite) based on specific porous structures that may benefit targeted applications. 

Figure 2.20 Some of the microscopic structures found in diatomite, showing their open porous structure.

Extrelute consists of coarsely porous diatomite with a granular structure and a high pore volume. This material is supplied in pre-packed columns containing various amounts of material. 

Biogenic silica structures also exhibit interesting structural properties. In particular, the large porosity of diatom frustules makes them excellent sorbents for a wide variety of processes, including dynamite preparation by immobilization of nitroglycerin or for water remediation purposes. Noticeably, these applications use diatomite earth (i.e., geological deposits of dead diatom frustules) rather than fresh silica [67]. This is also true considering another application of natural porous silica for filtration, as used in the brewery processes [68]. 

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