Verfahren zur Herstellung von Aluminium dotiertem Kieselgel zur chromatographischen Trennung freier Basen

摘要

Prepn. of Al-doped SiO2 gel (I) comprises: (a) preparing SiO2 (II) contg. little metal with microcrystalline centres and/or homogeneous distributed silanol gps. on the surface by heating commercially-available SiO2 with dil. acid and allowing to cool slowly; (b) shaking or boiling (II) with a (slightly) acidic aq. soln. contg. Al to produce Al-doped SiO2 (III), which is washed free from halogen; and (c) chemical modification of (III) by reacting with halo- or alkoxysilane in the presence of an organic, strongly basic catalyst (IV).