Apatite chromatography column system

Claim 1

A column system for use in chromatography comprising: a main column packed with an adsorbent composed of secondary particles formed by aggregation of fine primary hydroxyapatite crystal particles, said secondary particles having been sintered, wherein a sintering bond is formed between the aggregated fine primary hydroxyapatite crystal particles; and a precolumn provided at the fluid inlet into said main column so as to be connected in communication with or disconnected from said main column packed with a second adsorbent consisting of hydroxyapatite crystal particles having resistivity to the chemical and physical loads applied from the fluid introduced into the column, said second adsorbent being either of a first type hydroxyapatite crystal particles or a second type hydroxyapatite crystal particles, wherein said first type hydroxyapatite crystal particles having been produced by having an alkali act on crystal particles of brushite used as the starting material, and said second type hydroxyapatite crystal particles having been produced by the steps of heating brushite crystal particles used as the starting material, to a temperature range of not lower than the dehydration transition temperature and not higher than the decomposition temperature thereof, to cause dehydration and phase transition of the brushite crystal particles, and thus producing monetite crystal particles, and subsequently acting an alkali on the thus produced monetite crystal particles to produce hydroxyapatite substantially monocrystal particles.