硝酸 - 水系の低濃度域における気液平衡に及ぼす塩効 Title 果を利用した硝酸の濃縮 山本, 秀樹, 前田, 領平, 山口, 修平, 北口, 剛司, Author(s) 芝田, 隼次 Citation 化学工学論文集, 31(5): 331-337 Issue Date 2005 URL http://hdl.handle.net/10112/5537 Rights Type Journal Article Textversion publisher Kansai University http://kuir.jm.kansai-u.ac.jp/dspace/
31 5 pp. 331 337 2005 564 8680 3 3 35 x 0 40 mol% Ohe and Yokoyama, 1969 30 50 wt% 50 wt% 5 mol/dm 3 14 mol/dm 3 72.2% 13 300 13 25% 69% 6% Pauling Nissan Engineering, 1992 69 wt% 2005 1 25 24 2003 6 yhideki@kansai-u.ac.jp 3 Sloan, 1976; Vaillancourt, 1976 1. 1.1 Copyright 2005 The Society of Chemical Engineers, Japan 331
Fig. 2 Vapor liquid equilibrium of methanol water system at 101.3 kpa Fig. 1 Othmer-type equilibrium distillation apparatus Figure 1 350 cm 3 13 cm 3 NF30-FA 0.1 K 1.2 101.3 kpa Maripuri and Ratcliff, 1972 Figure 2 0.72% 0.36 K Herington 0.69% 0.20 K 2. 2.1 60% 98.0% MOV-212F U 473 K 24 2.2 2.2.1 50 wt% 50 wt% 200 g 5K 1 10 cm 3 BA-9116 101.3 kpa AT-510 0.1 mol/dm 3 NaOH AA-6800 ICPs- 1000 DA-130 298 K 332
Table 1 Vapor liquid equilibrium data of nitric acid (1) water (2) salt (3) systems at 101.3 kpa Mole fraction Liquid phase Vapor phase x 1 [ ] y 1 [ ] Boiling point t [ C] No salt 0.109 0.008 107.4 0.160 0.025 112.0 0.220 0.074 115.3 0.258 0.137 117.6 0.304 0.220 119.4 Mg (NO 3 ) 2 : 30 wt% 0.045 0.025 115.1 0.100 0.104 120.4 0.138 0.224 123.8 Mg (NO 3 ) 2 : 40 wt% 0.050 0.076 115.6 0.112 0.234 121.3 Fig. 3 Vapor liquid equilibrium of nitric acid water system at 101.3 kpa 2.2.2 50 wt% 5 mol/dm 3 400 g N-1000 340 K 1.0 kpa 320 K 1.0 kpa AT-510 0.1 mol/dm 3 NaOH 3. 3.1 101.3 kpa Ellis and Thwaites, 1957 Figure 3 0.3 0.4 101.3 kpa Table 1 Figure 4 0.38 393.8 K 40 wt% Ca (NO 3 ) 2 : 40 wt% 0.052 0.028 114.3 0.098 0.099 119.2 0.150 0.201 121.1 Ca (NO 3 ) 2 : 50 wt% 0.045 0.061 120.4 0.090 0.164 123.9 LiNO 3 : 30 wt% 0.052 0.022 116.1 0.098 0.082 120.5 0.150 0.163 123.7 0.254 0.390 126.3 0.309 0.530 124.2 LiNO 3 : 40 wt% 0.090 0.136 120.0 0.149 0.251 124.2 0.231 0.423 128.0 0.291 0.639 125.4 LiNO 3 : 50 wt% 0.051 0.107 132.0 0.101 0.242 133.8 0.155 0.398 132.6 NaNO 3 : 10 wt% 0.102 0.012 109.7 0.204 0.087 116.7 0.302 0.239 120.6 NaNO 3 : 20 wt% 0.101 0.019 112.1 0.205 0.111 118.8 Condition Experimental apparatus : Othmer-type 40 wt% 50 wt% 1 mol/kg Figure 5 1kg 31 5 2005 333
Fig. 4 Vapor liquid equilibrium of nitric acid water lithium nitrate system at 101.3 kpa Fig. 6 Relationship between crystallization ion radius and enthalpy of solution Fig. 7 Relationship between ionic radius and relative volatility ratio for nitric acid water salt systems Fig. 5 Vapor liquid equilibrium of nitric acid water salt systems at 101.3 kpa Ohtaki, 1990 Figure 6 Figure 7 a a s a s/a Figure 8 3.2 334
Table 2 Results of simple distillation for nitric acid water lithium nitrate system at reduced pressure Table 3 Result of simple distillation for nitric acid water system at reduced pressure Feed Distillate Salt concentration [wt%] Concentration Concentration Yield [mol/dm 3 ] [mol/dm 3 ] [%] 40.0 5.0 6.6 81.3 50.0 5.0 8.2 90.2 Conditions Amount of feed (salt free): 150 g, Temperature: 340 K, Pressure: about 0.8 kpa Feed Waste Distillate Concentration Concentration Yield Concentration Yield [mol/dm 3 ] [mol/dm 3 ] [%] [mol/dm 3 ] [%] 8.2 13.9 72.2 4.2 27.1 Conditions Amount of feed (salt free): 150 g, Temperature: 320 K, Pressure: about 0.8 kpa Table 4 Component Mass balance of refining process I (simple distillation) for nitric acid (1) water (2) litium nitrate (3) system shown in Fig. 9 Distillate [wt%] Feed [wt%] Waste [wt%] ➀ ➁ ➂ ➃ HNO 3 13.9 1.4 12.5 0 H 2 O 36.1 0.8 24.1 11.2 LiNO 3 50.0 50 0 0 Table 5 Component Mass balance of concentration process II (simple distillation) for nitric acid (1) water (2) system shown in Fig. 9 Feed [wt%] Waste [wt%] Distillate [wt%] ➄ ➅ ➆ HNO 3 44.0 31.9 12.1 H 2 O 56.0 16.9 39.1 Fig. 8 Relationship between relative volatility ratio and enthalpy of solution for nitric acid water salt system at 101.3 kpa 5.0 mol/dm 3 Table 2 Nissan Engineering, 1992 50.0 wt% 8.2 mol/dm 3 90.2% 5.0 mol/dm 3 50 wt% Table 3 320 K 40 14.0 mol/dm 3 72.2% 4.2 mol/dm 3 Figure 9 2 I II 5.0 mol/dm 3 14.0 mol/dm 3 Tables 4 5 Figure 9 I II 1 mol/kg 31 5 2005 335
Fig. 9 Refining and concentration process of nitric acid 5.0 mol/dm 3 50 wt% 8.2 mol/dm 3 90.2% 14.0 mol/dm 3 72.2% 5.0 mol/dm 3 14.0 mol/dm 3 3 3 3 x 1 x 0 1 Nomenclature mole fraction of low-boiling component in liquid at existing salt [ ] mole fraction of low-boiling component in liquid at salt free basis [ ] y 1 mole fraction of low-boiling component in vapor [ ] a relative volatility at salt free [ ] a s relative volatility at salt addition [ ] Literature Cited Ellis, S. R. M. and J. M. Thwaites; Measurement of Vapor Liquid Equilibrium for Nitric Acid Water System, J. Appl. Chem., 7, 152 (1957) Ohe, S. and K. Yokoyama; Distillation with Use of Salt Effect, Isikawajimaharimagihou, 9, 123 135 (1969) Maripuri, V. O. and G. A. Ratcriff; Measurement of Isothermal Vapor Liquid Equilibriums for Acetone n-heptane Mixtures using Modified Gillespie Still, J. Chem. Eng. Data, 17, 366 369 (1972) Nissan Engineering, ed.; Unit Operation Series. Revision and Supplement. Distllation. 8. The Practice of Distillation, 820, Concentration of Dilute Nitric Acid, Bessatsu Kagakukougyou, 35, 324 328 (1992) Ohtaki, H.; Hydration of Ion, Kyoritsusyuppan, Tokyo, Japan (1990) Sloan, J. G.; The Extractive Distillation Process for Nitric Acid Concentration Using Magnesium Nitrate, Adv. Chem. Ser., 155, 128 142 (1976) Vaillancourt, J. A.; Use of Magnesium Nitrate in the Eextractive Distillation of Nitric Acid, Adv. Chem. Ser., 155, 143 149 (1976) 336
Concentration of Nitric Acid Using the Salt Effect on Vapor Liquid Equilibrium of Nitric Acid Water Systems with Low Concentrations of Nitric Acid Hideki YAMAMOTO, Ryouhei MAEDA, Shuhei YAMAGUTI, Takeshi KITAGUTI and Junji SHIBATA Department of Chemical Engineering, Faculty of Engineering, Kansai University, 3 3 35, Yamate-cho, Suitashi, Osaka 564 8680, Japan Keywords: Salt Effect, Nitric Acid, Nitrate Salt, Vapor Liquid Equilibrium, Concentration When involatile salts are added to an azeotropic mixture, the so-called salt effect changes the vapor liquid equilibrium, and has a big influence on relative volatility. Aqueous nitric acid is an azeotropic mixture, and cannot be concentrated by ordinary distillation. In this study, we measured the vapor liquid equilibrium of nitric acid water nitrate salt systems with azeotropic composition (x 0 40 mol%) for recycling of nitric acid in solutions from semiconductor manufacturing and metal-surface treatment processes. Aluminum nitrate, magnesium nitrate, calcium nitrate, lithium nitrate and sodium nitrate were used as nitrate salts. For each salt tested the salting-out effect was confirmed and the azeotropic point was eliminated completely by adding salts at concentration of 30 50 wt%. Consequently, nitric acid could be separated by distillation from waste solution with a low concentration (under azeotropic composition) of nitric acid. Separation and concentration of nitric acid from dilute aqueous nitric acid was tested by simple distillation using 50 wt% lithium nitrate. As a result, nitric acid aqueous solution was concentrated from 5.0 to more than 14.0 mol/dm 3 (yield, 72.2%). 31 5 2005 337