A column method using 2, 2′-dipyridyl-tetraphenylborate-naphthalene as an adsorbent has been establishedfor the determination of trace amounts of iron. The optimum pH range for the adsorption is4.2-6.4. Naphthalene containing iron (II) complexes is dissolved in N, N-dimethylformamide and theabsorbance is measured at 525 nm. Beer's law is obeyed over the concentration range 3-45μg ofiron in 10 ml of N, N-dimethylformamide solution. The molar absorptivity was calculated to be 9.2×103 lmol-1cm-1 at 525 nm. Nine replicate analyses of a sample solution containing 25.0μg of irongave a mean absorbance of 0.411 with a relative standard deviation of 0.66%. The method has been successfully applied to the determination of iron in sea waters and common salts.
A method has been developed for the concentration and separation of molybdenum and vanadiumin seawater. The method consists of precipitation flotation as for uranium followed by ion exchange.The recovery of molybdenum and vanadium was each about 100% in the flotation. Molybdenum witha small amount of iron (III) was separated from vanadium and a large portion of iron (III) bypassing the solution of the scum adjusted to pH 1.5 through a column of Amberlite IR-120 in thehydrogen form, and vanadium was separated from iron adsorbed on the column by eluting with a3% sodium hydroxide solution. Complete separation of molybdenum from iron was achieved bypassing the effluent of 0.1 N sulfuric acid solution containing molybdenum and a small amount ofiron through a column of Amberlite IRA-410 in the Cl form and eluting with a 1 N hydrochloric acid solution.
Oil soaking characteristics of peat mat were investigated using viscous heavy oils and emulsified oils, and compared with those of polypropylene (PP) and palm mats. The quantity of oil soaked in fiber matsdepends on the bulk density of mats. The oil soaking mechanism was adequately explained by a simplemodel. The oil soaking capacity of peat mat was the highest for high viscous heavy oil C. It has been found, however, that the capacity is decreased with increasing water content of the emulsified oils.