Table 1 Chemical composition of the copper concentrate (mass%), Au* Ag* Cu Fe S Pb Zn SiO 2 Al 2O

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1 Netsu Sokutei Utilization of Thermodynamics in Extractive Metallurgy Katsunori Yamaguchi Received Sep.26, 2009; Accepted Oct.16, 2009 Historically thermodynamics was developed in order to describe the relation between heat and work, for example in steam engine. The traditional introduction to thermodynamics shows this traditional derivation. In metallurgy the application has been to relations between heat, temperature, pressure and chemical compositions. This field is often called metallurgical thermodynamics. Among the various, applicability of thermodynamics to extractive metallurgical processes, calculation methods combining stoichiometric relations with equilibrium constants and the availability of chemical potential diagrams are emphasized. For thermodynamically understanding of smelting processes, the phase equilibrium and distribution of minor elements among the metal, slag, and matte phases are reviewed. Keywords : metallurgical thermodynamics potential diagram distribution ratio 1 2 3,4 5, mass% 2009 The Japan Society of Calorimetry and Thermal Analysis. 255

2 Table 1 Chemical composition of the copper concentrate (mass%), Au* Ag* Cu Fe S Pb Zn SiO 2 Al 2O mass ppm mass% Table 1 8 CuFeS SiO 2 Al 2O 3 Fig.1 9 PbS PbO SO 2 PbO 99 mass% FeO SiO 2 CaO FeO x-sio 2- CaO mass% FeS-Cu 2S 3 Fig.1 Principal processes for extracting copper and lead from sulfide ore.. SiO 2 FeO x-sio mass%cu Cu 2S Cu 2S 99 mass% mass% 256

3 log K 2 n log a XmOn 2m n log a X log p O2 H 0 /2.303RT S 0 /2.303R (5) log po2 X X mo n a M a MmOn 1 log p O2 1/T Fig.2 H 0 /2.303R RT ln p O2 log p O2 log p O2Fig.2 C-O(6) Fig / T Relation between oxygen and 1/T for various metal-oxygen system., G 0 Ellingham Fig.2 logp O2 1/T X X mo n 1, G a 2 2m n X O 2 (g) 2 n X mo n (1) a 2/n XmOn a 2m/n p O2 X G G 0 RT ln (2) G 0 R T p kpa G 0 (2) K a 2/n XmOn G 0 RT lnk RT ln (3) a 2m/n X G 0 H S (4) (1) (5) p O2 G 0 H 0 T S 0 A BT (4) 2CO(g) O 2(g) 2CO 2(g) G 0 /J T 10) (6) log p O2 2 log(p CO2/p CO) 2950/T 8.98 (7) (7) CO-CO 2 p O2T p CO2/p CO Fig.2 CO 2/CO log p O2 PbO PbO Pb-PbO log p O2 p CO2/p CO 100 log p O2 PbO PbO CO(g) Pb CO 2(g) (8) Fe- FeO FeO p CO2/p CO 1 1 p CO2/p CO 100 log p O2 FeO PbO Pb PbO FeO PbO FeO a PbO a FeO K SiO 2,X,S (1) 2m n X S 2 (g) 2 X n ms n (9) 257

4 log po2 log p S2 Fig.3 Sulfur-Oxygen potential diagram at 1573 K. log K 2 n log a XmSn 2m n log a X log p S2 H 0 /2.303RT S 0 /2.303R (10) log p S2 1/T X O S log p O2 log p S2 Fig K M-S-O M M ms n M mo n a M a MmSn a MmOn 1 (1) (9) X n ms n O 2 2(g) X n mo n S 2 (g) (11) log K 2 log a n XmOn 2 a n XmSn log p S2 log p O2 (12) SO 2 Fig.3 p SO ) (1/2)S 2(g) O 2(g) SO 2(g) G 0 /J T (13) SO 2 p SO2 p S2 p SO2 p SO2 p SO % SO 2 p SO2 0.1 p SO2 0.1 FeS ZnS PbS Ni 3S 2 Cu 2S Cu 2S Cu 2S Fig.3 SiO 2 Cu-Fe- S-O-SiO K 2),11) Fig.4 Cu-Cu 2S-Cu 2O Fe-FeS- FeO FeO FeS SiO 2 pq 45 FeO FeS Cu 2S FeS pq Cu 2S C 0 Cu pq A B C pqrstp qr rs st tp p SO2 1 p SO2 0.1 A mass Cu 258

5 log po2 log N XOv log (γxmon) log (γo2) log p S2 Fig.4 Simplified Sulfur-Oxygen potential diagram for the system Cu-Fe-S-SiO 2 at 1573 K. B 75 mass Cu C D mass% X 14 X v O 2 (g) XO v (14) 2 CuO 0.5 FeO 1.5 AlO 1.5 Cu 2O Fe 3O 4 Al 2O 3 Fig.5 XO v X mo n 12) XO v X mo n Fig.5 (15) n T 100 g X M X n T (14)(16) Activity coefficients of oxides plotted against mole fraction of oxides in the slag at 1523 K. n X mass%x a XO γ XON XO γ XO γ XO (15) n T M xn T a XOv [n T](γ XOv)(mass%X) K (16) a X p v/2 O2 (nt)[γ X][mass%X] p v/2 O2 X Fig.6 n T [n T] 1.53 (n T) 1.47 {n T} ),13) log N XmOn 259

6 (nt) {nt} [nt] L s/m X mass% Cu in matte Fig.6 Total moles of constituents in 100 grams of slag, matte and copper phases. log p O2 X L s/m X (17) (mass%x)/[mass%x] X (18) (mass%x) K(n T)[γ X]p v/2 O2 L s/m X (17) [mass%x] [n T](γ XOv) logl X s/m logk log[γ X] log(γ XOv) (n T) v log logp O2 (18) [n T] 2 K n T L s/m X p O2 v/2 X XO v Fig.7 14,15) A FeO x-sio 2 C FeO x-cao-sio 2 D FeO x-cao 2 1 p O2 p O2 Fig.7 Distribution ratios of metals between the FeO x- SiO 2-CaO slag and liquid copper at 1573 K in relation with oxygen potential. FeO x-sio 2 FeOx-CaO FeOx-CaO-SiO2 FeO x-cao SiO 2 FeO x-cao FeO x-sio 2 PbO SiO 2 CaO FeO x-cao-sio 2 PbO AsO 1.5 Fig.8 Fig.9 16,17) PbO FeO x-sio 2 FeO x-cao AsO 1.5 PbO FeO x-sio 2 FeO x-cao Fig.10 18) mass%cu mass%cu 260

7 mass% Ca0 mass% FeO x mass% SiO 2 mass% Cu in slag Fig.8 Activity coefficient of PbO in the FeO x-sio 2- CaO slag at 1573 K. mass% Ca0 mass% SiO 2 mass% Cu in matte Fig.10 Oxidic and sulfidic dissolution of copper in the slag along with total copper content in the slag against matte grade at 1573 K. mass% FeO x Fig.9 Activity coefficient of AsO 1.5 in the FeO x-sio 2- CaO slag at 1573 K. 65 mass%cu mass%cu mass%cu mass%cu (mass%cu)o (mass%cu)s 18-20) (mass%cu) (mass%cu) O (mass%cu) S (19) CuS 0.5(l) 1/4O 2(g) CuO 0.5(l)+1/4S 2(g) (20) (20) (mass%cu) O [K(n T) M Cu a CuS0.5 /(γ CuO0.5)](p O2/p S2) 1/4 (21) K (n T) 100g a CuS0.5 CuS 0.5 (γ CuO0.5) CuO 0.5 M Cu (mass%cu) S a CuS0.5(n T) M Cu / (γ CuS0.5) (22) (γ CuS0.5) CuS 0.5 Fig.10 (mass%cu) S mass%cu (mass%cu) O

8 解説 13) A. Yazawa, Proc. 2nd. Int. Sympo. On Metall. Slags and Fluxes, Lake Tahoe, Nevada, 701 (1984). 14) A. Yazawa and M. Hino, ISIJ International 33, 79 ルや環境調和型の金属生産プロセスの創製も今後の重要な課題であり従来の不純物除去に関する研究に加えプロセス全体のエネルギー評価などへも製錬熱力学の利用が期的な尺度は未だ確立していない横川による本誌の巻頭 (1993). 15) Y. Takeda, S. Kanesaka, M. Hino and A. Yazawa, Pyrometallurgy'95, IMM, Cambridge, 285 (1995). 16) M. Kudo, E. Jak, P. Hayes, K. Yamaguchi, Y. Takeda, Metal. Mater. Trans.B 31B, 15 (2000). 17) Y. Takeda, Zinc & Lead' 95, CIM and MMIJ, Sendai, 766 (1995). 18) G. Roghani, Y. Takeda, K. Itagak Metal. Mater. Trans. B 31B, 705 (2000). 19) M. Nagamori, J. Metals 46, 65 (1994). 20) Y. Takada, Yazawa Int. Sympo. Metall. Mater. Process. Vol.1, TMS, San Diego, 341 (2003). 言 21) にあるようにその尺度を導くヒントが生成エンタル 21) 横川晴美熱測定 (2008). 待される金属スクラップ中の不純物は鉱石などとは異なり人工的に混在しているものであるため従来の金属製錬で取り扱っていた物質系より複雑多元化しているまたスクラップ中にはハロゲンを含む有機物質が混入していることも多く廃棄物処理や金属製錬においてダイオキシンや塩化物の問題を引き起こしている今後はこのような多成分系における熱力学データの測定集積評価活動や無機物質のみならず有機物質も製錬熱力学の研究対象となると考える酸化物融体の塩基度は金属製錬においては重要な知見を与えるが相対的な塩基度は分かっても絶対ピー混合エンタルピー活量などの熱力学諸量の中に宿要旨っているのかもしれない熱測定会員の皆様と協力しながら学問としての熱力学の理解を深め精度の高い熱力学歴史的に古く学問体系を築き上げられた化学熱力学の金データの測定手法の開発と熱力学データベースの構築によ属製錬への適用は製錬反応に対する理解を深め操業改り熱力学の利用をさらに広げていきたいと考えている善の指針を示し不純物の除去など金属製錬を考えるうえ本稿をまとめるにあたっては矢澤彬板垣乙未生およで大きな威力を発揮してきており製錬熱力学と呼ばれるび故武田要一らの論文と資料を参考にさせていただいたこ学問領域にまで発展している本稿では非鉄金属製錬におとを記してこれらの著者に対して謝意と敬意を表するける熱力学の応用例を概説するポテンシャル図は製錬の反応過程を理解するうえで有効であるまた不純物の除文献去やスラグへ目的金属の損失を検討するうえで異相間の 1) 後藤佐吉日本鉱業会誌 97, 107 (1981). 分配平衡と溶解度の熱力学的な考察が行われている 2) A. Yazawa Metall.Trans.B 10B, 307 (1979). 3) H. H. Kellogg, International Symposium on Quantitative Description of Metal Extraclion Processes, ed. by N. J. Themelis and P. F. Duby, TMS-AIME, New York, 267 (1991). 4) D. G. C. Robetson, TMS EPD Congress, 347 (1995). 山口勉功 Katsunori Yamaguchi 岩手大学工学部マテリアル工学科 Department of Materials Science and Technology, Faculty of Engineering, Iwate University TEL FAX benko@iwate-u.ac.jp 研究テマ金属熱化学金属製錬趣味ロシア文学落語 5) 板垣乙未生資源と素材105, 195 (1989). 6) 山口勉功 J.MMIJ 125, 375 (2009). 7) 横川晴美新熱測定の進歩1, 37 (1992). 8) 中村崇編サステナブル金属素材プロセス入門アグネ技術センター(2009). 9) 日本金属学会編, 金属製錬工学丸善 (1999). 10) O. Knacke, O. Kubaschewski and K. Hesselmann, Thermochemical Properties of Inorganic Substances, Springer-Verlag, Berlin, Heidelberg, (1991). 11) A. Yazawa, Can. Met. Quart., 13, 443 (1974) MS-O. 12) Y. Takeda, S. Ishiwata and A. Yazawa, Trans. Japan Inst. Metals, 24, 518 (1983) Netsu Sokutei 36

Rate of Oxidation of Liquid Iron by Pure Oxygen Shiro BAN-YA and Jae-Dong SHIM Synopsis: The rate of oxidation of liquid iron by oxygen gas has been s

Rate of Oxidation of Liquid Iron by Pure Oxygen Shiro BAN-YA and Jae-Dong SHIM Synopsis: The rate of oxidation of liquid iron by oxygen gas has been studied using a volume constant technique. The process