抄録
Studying the isolation of crystalline vitamin B_<12> from activated sludge in industrial scale, a plan for pilot plant was worked out as follows : (1) Dried raw material is extracted with 5 parts of water at 90-100℃ for an hour.(2) Vitamin B_<12> in the filtrate is adsorbed on 0.3% of active carbon.(3) Adsorbent is washed with 15% acetone to remove impurities and then eluted with 50% acetone.(4) Concentrating the acetone eluate under reduced pressure, the vitamin is extracted by shaking the concentrate with phenol-butanol mixture.(5) The solvent layer is stirred with ether and water to transfer vitamin B_<12> to aqueous layer.(6) The aqueous layer obtained is rum through the column of Amberlite IRC-50 to adsorb the vitamin followed by the elution with 0.1N HCl in 75% acetone.(7) To remove hydrochloric acid, the eluate is run through the column of IR-4B. The acetone eluate of pink color is concentrated to a small amount. Finally, vitamin B_<12> is crystallized from acetone. One gramme of vitamin B_<12> may be obtained from one ton of dried activated sludge. Details of each process will be described in other papers.
