抄録
It was reported in the previous literatures that molybdenum, vanadium and uranium contained in sea water are concentrated in bittern. Therefore, we conducted the present study for the purpose of gathering these constituents from bittern by adsorption of ferric hydroxide. This paper gives data on adsorption curves obtained by experiments which were conducted to find the relationship between pH and adsorption ratio. Optimum pH of adsorption was 3 to 4 in molybdenum, 3 to 7 in vanadium and above 6 in uranium respectively, but only adsorption pH of uranium changed in case of co-existence with carbonate ion, and it adsorbed with pH 7 to 8 in this case.
In addition, this paper gives data on desorption curves for water extraction from adsorbent obtained by experiments which were conducted to find the relationship between pH and desorption ratio. pH of desorption was above 4 in molybdenum, above 7 in vanadium and below 6 in uranium repectively, as pH becomes the higher, desorption of molybdenum and vanadium becomes more complete. Desorption of uranium was done above pH 9 in case of Co-existence with carbonate ion, These results showed a possibility of seprating molybdenum, vanadium and uranium from each other by application of adsorption and desorption. It was also possible to separate molybdenum from vanadium by application of anion exchange column.
Moreover, the methods of determining vanadium by N-benzoyl-N-phenyl-hydroxylamine and uranium by 1, 2-pyridylazo-2-naphthol were checked and improved, and these methods were applied to bittern and others with good results.
