Logo
Prev
search
Print
addthis
Rotate
Help
Next
Contents
All Pages
Browse Issues
Home
'
e-Science : April 2012 Issue 1
Contents
FEATURE like the frame of a building. This framework structure is open with large pores or chan- nels that permeate the structure. Zeolites are one example of a porous material made from the elements silicon, aluminium and oxygen. Zeolites are microporous – mean- ing they have pores with dimensions of less than 2 nm - solids with well-defined structures. Due to these structural proper- ties, zeolites are often also referred to as molecular sieves. Zeolites are used in a variety of applications with a global market of several million tonnes per annum. Major uses of relevance to our day-to-day lives are in refining of crude oil (in the ‘cracking’ of long chain hydrocarbons into shorter, more useful compounds), ion-exchange (water softening and purification), and in the sepa- ration and removal of gases and solvents. As an example of the benefits of using porous nanomaterials such as Zeolites, it is estimat- ed that ‘cracking’ by Zeolites in the petro- chemical industry generates $40 billion of additional value and saves 400 million bar- rels of crude oil per year. Another class of microporous nanomateri- als that can be synthesised by chemists are metal-organic frameworks (MOFs), so-called because they are composed of metal or metal-oxide ‘nodes’ and organic molecule ‘links’. These materials can be prepared by simply mixing together the components. One of the reasons that MOFs are attracting considerable current research effort is their unique structural properties, including: ro- bustness, high thermal and chemical stabili- ties, unprecedented internal surface areas (up to 10,000 m2/g), large pore volumes (up to 90%) and low densities (down to 0.21 g/cm3). To put the large surface areas into context, 10,000 m2/g equates to having the area of approximately two football fields TAP FOR FULL SCREEN SLIDESHOW 31 HAVE A QUESTION? / FEEDBACK: e-science.magazine@adelaide.edu.au FEATURE
Links
Archive
July 2012 Issue 2
Navigation
Previous Page
Next Page
