Effect of Heating Soil upon the Absorption of Dye Stuff by the Soil III

Abstract

By the previous report, it was understood that the effect of heating soils at increasing temperatures, from 300℃ to 600℃, influenced upon the dye absorption in two ways, increasing and decreasing. The absorption was increased with the soil of volcanic ash origin and of a lower ratio of SiO_2 to Al_2O_3,but it was decreased with the acid mineral soil of a higher ratio of SiO_2 to Al_2O_3. This time, the effect of removing constituents, dissolved by the mixture of oxalic acid and ammonium oxalate, from the soil to the absorption was examined, resulting in the same way with the above soils as the absorption being decreased. Compared to the previous result, the constituents, dissolved by the mixture, seemed to cause the absorption to be increased with an increase of heating temperature remarkably with the soil of a lower ratio of SiO_2 to Al_2O_3 and of volcanic ash origin.