Welcome to THEREDA

The Thermodynamic Reference Database (THEREDA) is designed for geo-chemical models in the context of a radioactive waste repository. The primary focus is on the correct calculation of the solubilities of radionuclides, fission products and matrix elements (construction materials and mineral phases of the surrounding host rock).

THEREDA especially addresses high-salinity aqueous solutions (brines) and therefore supports the Pitzer ion-interaction approach. Great effort has been made to ensure the internal consistency of the data.

For the oceanic salt system, THEREDA is applicable in the temperature range from 0 to 110 °C, for some subsystems even beyond. As such, THEREDA is the only database in the world that polythermally covers the entire system of oceanic salts. The current radionuclide selection includes actinides (Th, U, Np, Pu, Am, Cm) and fission products (Se, Sr, Tc, Cs). There is also data for some heavy metals (Pb, Zn) available. The majority of the data for these radionuclides is valid for 25 °C.

THEREDA can export ready-to-use parameter files in the formats of commonly used geochemical codes: Geochemist's Workbench and PHREEQC/PhreePlot.

THEREDA's data set is regularly benchmarked by recalculating experimental measured values, with all results documented in the "Application examples" section.

Read more ▶

Application examples

An extensive survey of all tested systems can be accessed using the menu item Application Examples

Example 421
Example 586
Example 588
Example 341
Example 345
Example 174
Example 175
Example 176
Example 177
Example 178
Example 179
Example 180
Example 181
Example 574
Example 215
Example 551
Example 550
Example 552
Example 64
Example 571
Example 572
Example 573
Example 575
Example 592
Example 593
Example 595
Example 599
Example 570
Example 594
Example 204
Example 549
Example 182
Example 183
Example 184
Example 185
Example 186
Example 187
Example 589
Example 188
Example 189
Example 190
Example 590
Example 504
Example 507
Example 5
Example 516
Example 523
Example 214
Example 553
Example 554
Example 556
Example 76
Example 576
Example 569
Example 75
Example 577
Example 579
Example 581
Example 596
Example 555
Example 568
Example 580
Example 225
Example 558
Example 314
Example 4
Example 3
Example 8
Example 531
Example 505
Example 510
Example 519
Example 526
Example 10
Example 13
Example 20
Example 561
Example 557
Example 559
Example 583
Example 582
Example 9
Example 524
Example 546
Example 23
Example 12
Example 6
Example 11
Example 532
Example 525
Example 328
Example 332
Example 335
Example 59
Example 535
Example 560
Example 564
Example 563
Example 565
Example 566
Example 327
Example 42
Example 32
Example 87
Example 56
Example 538
Example 88
Example 238
Example 239
Example 240
Example 241
Example 89
Example 90
Example 91
Example 359
Example 311
Example 361
Example 53
Example 57
Example 58
Example 60
Example 61
Example 536
Example 537
Example 224
Example 63
Example 68
Example 73
Example 78
Example 80
Example 81
Example 82
Example 312
Example 313
Example 92
Example 93
Example 94
Example 95
Example 96
Example 97
Example 98
Example 99
Example 100
Example 101
Example 102
Example 126
Example 67
Example 86
Example 79
Example 66
Example 69
Example 62
Example 71
Example 84
Example 72
Example 85
Example 119
Example 120
Example 121
Example 122
Example 127
Example 128
Example 129
Example 130
Example 131
Example 134
Example 135
Example 136
Example 137
Example 138
Example 140
Example 141
Example 142
Example 143
Example 144
Example 145
Example 146
Example 147
Example 114
Example 115
Example 148
Example 149
Example 150
Example 151
Example 152
Example 326
Example 277
Example 210
Example 208
Example 211
Example 206
Example 217
Example 228
Example 226
Example 278
Example 279
Example 280
Example 281
Example 282
Example 283
Example 284
Example 357
Example 285
Example 286
Example 287
Example 288
Example 333
Example 334
Example 203
Example 219
Example 213
Example 216
Example 218
Example 220
Example 221
Example 222
Example 223
Example 212
Example 329
Example 336
Example 337
Example 338
Example 340
Example 342
Example 343
Example 344
Example 346
Example 347
Example 339
Example 348
Example 349
Example 350
Example 351
Example 352
Example 353
Example 354
Example 356
Example 358
Example 360
Example 362
Example 363
Example 364
Example 365
Example 366
Example 367
Example 368
Example 369
Example 370
Example 372
Example 373
Example 374
Example 375
Example 376
Example 378
Example 380
Example 381
Example 382
Example 383
Example 397
Example 384
Example 385
Example 386
Example 387
Example 388
Example 389
Example 390
Example 391
Example 392
Example 393
Example 394
Example 395
Example 398
Example 400
Example 402
Example 403
Example 404
Example 410
Example 411
Example 412
Example 413
Example 415
Example 416
Example 418
Example 414
Example 399
Example 409
Example 419
Example 420
Example 422
Example 396
Example 423
Example 424
Example 425
Example 426
Example 427
Example 428
Example 429
Example 441
Example 442
Example 443
Example 444
Example 445
Example 430
Example 474
Example 406
Example 433
Example 438
Example 439
Example 440
Example 446
Example 447
Example 448
Example 449
Example 450
Example 451
Example 452
Example 453
Example 435
Example 436
Example 437
Example 434
Example 454
Example 417
Example 455
Example 456
Example 457
Example 458
Example 459
Example 460
Example 461
Example 462
Example 463
Example 464
Example 465
Example 466
Example 467
Example 468
Example 469
Example 473
Example 475
Example 476
Example 477
Example 478
Example 479
Example 480
Example 481
Example 482
Example 483
Example 484
Example 485
Example 486
Example 487
Example 488
Example 489
Example 490
Example 472
Example 491
Example 492
Example 493
Example 494
Example 495
Example 496
Example 497
Example 498
Example 499
Example 500
Example 501
Example 502
Example 503
Example 506
Example 508
Example 509
Example 511
Example 513
Example 515
Example 355
Example 585
Example 584
Example 587
Example 534
Example 517
Example 520
Example 522
Example 527
Example 533
Example 543
Example 541
Example 540
Example 544
Example 542
Example 528
Example 310
Example 401
Example 7
Example 54
Example 514
Example 601
Example 74
Example 77
Example 202
Example 70
Example 613
Example 539
Example 547
Example 1
Example 83
Example 209
Example 52
Example 606
Example 55
Example 65
Example 567
Example 205
Example 408
Example 603
Example 591
Example 602
Example 604
Example 607
Example 608
Example 609
Example 610
Example 611
Example 612
Example 207
Example 2
Example 624
Example 545
Example 614
Example 227
Example 627
Example 578
Example 631
Example 625
Example 172
Example 630
Example 112
Example 113
Example 116
Example 628
Example 649
Example 647
Example 651
Example 548
Example 652
Example 562
Example 658
Example 657
Example 659
Example 471
Example 470
Example 660
Example 664
Example 665
Example 670
Example 662
Example 661
Example 666
Example 667
Example 668
Example 663
Example 672
Example 673
Example 674
Example 605
Example 330
Example 331
Example 405

Data release 2023

The THEREDA management board announces a new data release. Major changes or additions compared to the former release are:

  • Systems NaOH - Mg(OH)2 - Ca(OH)2 - CO2(g) – H2O(l) (polythermal)
  • Systems Mg2+ – Cl – OH – H2O(l) (polythermal)
  • Systems Na+ – Mg2+ – Cl – OH – H2O(l) (polythermal)
  • Systems Zn2+ – Na+ – K+ – Mg2+ – Ca2+ – Cl – SO42− – OH – H2O(l) (25°C)
  • U(+IV)-Hydrolysis and -solubility: Systems U(+IV) – Na+ – Mg2+ – Ca2+ – H+ – OH – Cl – H2O(l) (25°C)
  • Systems Al(OH)4 – Si(OH)4(aq) – Na+ – K+ – Ca2+ – Mg2+ – Cl – SO42− – CO32− – H2O(l) (polythermal)
  • Double salt CsCl-NaCl and solid solution (25 °C)
  • Update for systems O2(g) – Na+ – K+ – Mg2+ – Ca2+ – Cl – SO42− – CO32− – PO43− – OH – H2O(l)(polythermal except for carbonates and phosphates)

The complete release has been extensively tested in 296 test cases including more than 1400 numerical results for the following codes:

  • Geochemist's Workbench
  • PHREEQC

Support for CHEMAPP and TOUGHREACT has been abandoned. As in the former release we also offer a JSON-formatted version.

Due to the increasing complexity of the database it is possible to run calculations for systems for which THEREDA isn't qualified. Therefore, users are advised, to have a look on our continously growing list of application examples.

On 2024-04-08 the release was revised. Fixed errors:

  • Water stability line at p(H2) = 1 atm was wrong (GWB only)
  • Miscibility gap in solid solution SO4-CO3-AFt_ss was wrong

Key References

If you want to read more on THEREDA or cite the THEREDA database in your publications, you can use these references:

Project Funding

THEREDA is funded by BGE – the federal company for radio-active waste disposal, with the contract number 45181017.