Porous carbon-mineral nanocompositesPublished by Astacus on Пт, 01/06/2017 - 15:36
A variety of carbon-mineral composites (CMC), especially carbon-nanosilica and carbon nanoparticles bound to various solid matrices was prepared using different methods. There are CMC with nonporous and strongly porous carbons with the specific surface area of 50-1500 m2/g. The CMC characteristics are controlled by choice of precursors, reaction and treatment conditions.
There are several types of composites:
- mechanical mixtures differently treated;
- carbonized organics at a solid surface;
- simultaneous synthesis of carbon precursors (e.g. polymers) and mineral or metallic particles with subsequent carbonization of organics;
- carbons prepared by physical or chemical vapor deposition onto a substrate from the gas phase.
Carbon deposits can represent nonporous nanoparticles (NPNP) that is strong disadvantage for the use of composites as adsorbents; i.e., composites as adsorbents should include porous carbon nanoparticles. NPNP/mineral composites can be effective fillers of polymeric materials.
The specific surface area and pore volume of CMC can be varied in a wide range of 300-1500 m2/g and 0.5-1.5 cm3/g, respectively. The mineral matrices can include only individual silica or complex oxides based on silica. Carbon deposits can contain various heteroatoms providing specific surface properties of CMC that is of importance for their application in industry and for analytical purposes.
Nano/meso/macroporous carbon-mineral composites of various types including porous carbon nanoparticles bound to mineral nanoparticles (fumed nanooxides with silica, alumina, titania or complex nanooxides) can be prepared as adsorbents for polar and nonpolar compounds of various molecular weights, especially for fast and effective adsorption of toxic gases from air flow and for purification of water from pollutants. Introduction of such heteroatoms as O, N, P, S into carbon phase or metal particles provide additional differentiation of surface properties that is of importance from practical point of view.
Faculty of Chemistry; Department of Chromatographic Methods; Maria Curie-Skłodowska University
Chuiko Institute of Surface Chemistry