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Narrow-pore (Type A) Silica Gels
Type A silica gels exhibit narrow pore diameter values. They are normally used as catalyst carriers, adsorbents or variable pressure adsorbents. Through our silica gel customisation service we are able to supply these materials and to fine-tune their properties. The examples listed below are representative examples. The particle size, pore size and specific surface area of the silica can be customised as per your requirements. Please note that a lead time and minimum order size may be applicable when placing an order.
Please contact us to discuss your requirements or to request a quote.
Wide-pore (Type C) Silica Gels Silica gels designated as Type C exhibit large pore sizes and a surface that is populated by silicon-hydride (Si-H) groups as opposed to silanols (Si-OH). These sorbents are frequently employed in the following areas of industrial and analytical chemistry:
Aqueous normal phase chromatography (ACNP) The hydride-rich surface of an ACNP stationary phase is unique in comparison to the silanol-populated equivalent of regular silica. Mobile phases for ACNP are based on a solvent mixture comprising a polar organic solvent (for example methanol or acetonitrile) and water. Polar solutes such as acids and amines are most strongly retained, with the retention decreasing as the amount of water in the mobile phase is increased. Normally, the amount of nonpolar solvent in the mobile phase is at least 60% and the exact point of increased retention depends on the nature of the solute and the type of organic co-solvent in the mobile phase. A true ANP stationary phase can switch from normal to reverse phase mode and vice versa when the proportion of water in the eluent is altered. Hydride-rich Type C sorbents therefore allow users to employ a continuum of solvents from 100% aqueous to 100% organic.
Material Harvest® Wide-Pore (Type C) Silica Gels The following table summarises the grades of Type C silica gels that we are currently able to supply. The pore size, pore volume and surface area can be adjusted within each specified range to match your requirements.
* Adjustable within the specified range Please contact us to discuss your requirements or to request a quote. |
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