ブンゼン反応溶液の密度及びポリヨウ化水素酸の粘性率

Density of Bunsen reaction solution and viscosity of poly-hydriodic acid

久保 真治  ; 吉野 公二*; 武本 純平*; 笠原 清司  ; 今井 良行  ; 小貫 薫

Kubo, Shinji; Yoshino, Koji*; Takemoto, Jumpei*; Kasahara, Seiji; Imai, Yoshiyuki; Onuki, Kaoru

熱化学水素製造法ISプロセスにかかわる物性データベース整備の一環として、ブンゼン反応溶液である硫酸相溶液及びヨウ化水素相溶液の密度データを取得した。濃度045wt%の硫酸及び同液に(I+HI)を02mole%混入させた模擬硫酸相溶液、また、ポリヨウ化水素酸(I: 017mole%, HI: 115mole%)及び同液にHSOを02mole%混入させた模擬ヨウ化水素相溶液について、振動式密度計を用いて、560Cの温度範囲の密度を測定した。さらに、測定データの解析から、いずれの溶液についても、新たに定義したヨウ素原子分率を用いることにより、ヨウ素及びヨウ化水素の濃度が液密度に与える効果を統一的に表現できることを見いだし、この知見をもとに、組成及び温度から密度を推算する実験式を得た。また、これまで知見のなかったポリヨウ化水素酸の粘性率について、I: 017mole%, HI: 115mole%の組成範囲において、振動式粘度計を用いて、540Cの温度範囲の実測データを取得し、組成及び温度から粘性率を推算する実験式を得た。

Densities of Bunsen reaction solutions in the iodine-sulfur process were measured with an oscillating U-tube density meter. Two types of the solutions were prepared to simulate sulfuric acid solutions and hydriodic acid solutions of the Bunsen reaction step. The former solution ranged in concentration from 0 to 45 wt% of sulfuric acid containing HI and I of 0-2 mole%; the latter solution contained 0-17 mole% I, 1-15 mole% HI and 0-2 mole% HSO. The temperature of the measured solution were 10-60 C. It was found that, in both solutions, the effect of HI and I concentration on the density could well be represented by using a kind of mole fraction of iodine atom. Based on the finding, a set of correlation equations between the densities and the compositions were derived. Additionally, viscosities of ploy-hydriodic acid were measured using an oscillating viscosity meter in temperature range of 5-40 C, and in the composition range of 0-17 mole% I and 1-15 mole% HI; a empirical equation to calculate viscosity from the composition and the temperature are obtained.