| 摘要 |
PROBLEM TO BE SOLVED: To obtain lightweight pipe-shaped fine particulate iron oxide having a large surface area by mixing iron bacteria forming filaments with iron powder and water, allowing the mixture to stand, drying and heating a product formed by the iron bacteria. SOLUTION: A mixture of 1 l water at 6-35 deg.C with 10-1,000 mg, preferably 10-100 mg iron bacteria forming filaments such as Leptothrix, Sphaerotilus or Haliscomenbacter and >=1 mg, preferably about 500 mg iron powder is allowed to stand for 5-7 days while blowing CO2 into the water for 30 sec at about 1 l/min rate and intervals of 60 min, divalent iron dissolved in the water is oxidized to trivalent iron by the iron bacteria and this trivalent iron is deposited on the outsides of the iron bacteria. The resultant product is extracted, dried at about 30 deg.C for about 10 min and heated at 700-900 deg.C for about 30 min to obtain the objective pipe-shaped fine particulate iron oxide of different colors. |
