The determination method for nickel in mineral springs and some applications of it have been described. The method of extracting nickel was taken from Sandell’s report, which is based on the extraction of nickel dimethylglyoxime from ammoniacal citrate solution using chloroform. For the purpose of obtaining an accurate determination, some improvements were made on Rollet’s method; as the concentration of ammonium hydroxide in the final solution was made higher, the reproducibility was increased, and therefore, Pulfrich photometer could be employed instead of Duboscq colorimeter. The mean error of the determinations did not exceed ±2 per cent. Some fifteen samples of acid vitriol springs were analysed in connection with nickel and a few other elements. The richest in nickel was Wakesui, Okayama Prefecture, with the richest total residue and iron content. The percentage of nickel in the total residue ranged from 0.00026 to 0.0087%, and the average is 0.0024%, showing a far higher value against either Clarke number for nickel or the percentage of the mean nickel content of igneous rocks, while the ratio Ni/Fe of the present analyses covers the range from 0.67×10−4 to 8.59×10−4, the average of which is 2.68×10−4, far less than either 2.02×10−3 of Clarke number or 5.81×10−3 of igneous rocks. Finally, details on some springs, —Wakesui, Okayama Prefecture, Aoki, Yamanasi Prefecture, and Kinkei, Totigi Prefecture—have been related. The distribution of nickel between the ocherous ferric hydroxide precipitated from the water of Kinkei and its filtrate has been represented and the answer to the question whether the deposit of ferric hydroxide from waters of. the kind accompanies nickel or not, suggested.
1. The separation of tert-butanol by the distillation from diluted aqueous sulphuric acid solution has been studied as the method of separation of tert-butanol from the absorption product of isobutylene with sulphuric acid without neutralising acid with alkali. By the suitable dilution of the absorption product, tert-butanol can be separated in the theoretical yield of about 68–80%, with small regeneration and polymerisation of isobutylene. The regeneration of isobutylene increases and the polymerisation takes place in a considerable extent with increasing concentration of acid. The increase in the absorption of isobutylene with a definite amount of acid, or the use of fractionating column in the distillation increase the regeneration of isobutylene. 2. The distillation in the presence of pumice powder increases markedly the formation of isobutylene with the decrease in the yield of tert-butanol. An explanation has been given. 3. The marked increases in the formation of gaseous product from liquid reaction mixture by the addition of powder of porous substances, such as pumice powder, and by the vigorous mechanical stirring have been named as “the porous substance effect” and “the stirring effect” respectively, both being named generically as “the agitation effect”. Some examples of the “agitation effect” observed hitherto have been summarized.