Environ. Chem. 2010, 7, 259–267. doi:10.1071/EN10008_AC
©CSIRO 2010
Accessory publication
Palladium(II) sequestration by phytate in aqueous solution – speciation analysis and ionic medium effects Antonio Gianguzza,A Demetrio Milea,B Alberto PettignanoA and Silvio Sammartano B,C A
Dipartimento di Chimica Inorganica e Analitica ‘Stanislao Cannizzaro’, Università di Palermo, Viale delle
Scienze, I-90128 Palermo, Italy. B
Dipartimento di Chimica Inorganica, Chimica Analitica e Chimica Fisica, Università di Messina, Salita
Sperone, 31, I-98166 Messina (Vill. S. Agata), Italy. C
Corresponding author. Email:
[email protected]
Table A1. Phytate protonation constants in NaClaq[36] and in NaNO3aq[35] at I = 0.1 mol L–1 and t = 25°C logβrH refer to equilibrium: Phy12– + r H+ = HrPhy(12–r)–; logΚrH in parenthesis refer to equilibrium: H+ + Hr1Phy
Medium NaClaq
logβ1H 9.58
NaNO3aq
9.48
logβ2H 19.42 (9.84) 19.46 (9.98)
(12–r+1)–
= HrPhy(12–r)–
logβ3H 28.92 (9.50) 28.99 (9.53)
logβ4H 37.06 (8.14) 37.19 (8.20)
logβ5H 43.56 (6.50) 43.68 (6.49)
logβ6H 48.81 (5.25) 48.85 (5.17)
logβ7H 51.69 (2.88) 51.87 (3.02)
Table A2. Literature values for palladium(II) hydrolysis in NaClO4aq at t = 25°C and different ionic strengths logβ10r refer to equilibrium: Pd2+ + r H2O = Pd(OH)r(2–r) + r H+ I (mol L–1) 0A 0.05 0.1 0.1B 0.1 0.18 0.5 0.5–1C variable 1 1 A
logβ10–1 ~–1.3 –1.2 –1.38 –2.08 – –1.76 –1.77 –5.65 – –3.0 –
log β10–2 ~–1.85 –2.2 –2.36 –3.99 –3.76 –2.82 –4.24 –12.2 ~–8.7 – –4.1
Values extrapolated by a Debye–Hückel type equation.
Values at t = 17°C.
B
C
Only one value given by the authors in this ionic strength range.
D
Literature values reported by authors.
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logβ10–3 – – – –15.92 – – – –19.85 ~–20.5 – –15.05
logβ10–4 – – – –28.7 – – – –28.5 – – –
References [24] [24] [24] [25] [19] [24] [19] [18] [18]D [28] [19]
Environ. Chem. 2010, 7, 259–267. doi:10.1071/EN10008_AC
©CSIRO 2010
Table A3. Literature values for palladium(II) hydrolysis and chloride complexes chloride aqueous media, at different temperatures and ionic strengths logβpqr refer to equilibrium: p Pd2+ + q Cl– + r H2O = PdpClq(OH)r(2p–q–r) + r H+; data in parenthesis refer to logKPdClq for the stepwise equilibrium: PdCl(q-1)(2–q+1) + Cl– = PdClq(2–q). ?, not specified Medium
KCl ClO4 / Cl– NaClO4 / Cl– NaCl NaCl NaCl KCl NaCl NaCl Cl– / ClO4– NaCl NaCl ? NaClO4 / NaCl HClO4 / NaCl HClO4 / HCl NaCl NaCl KCl NaClO4 / Cl– NaClO4 / Cl– NaCl NaCl NaCl NaCl H2SO4 / Cl– A
I (mol L–1) 0 0 0 0 0 0.1 0.1 0.1 0.105 0.305 0.5 0.5 0.5 0.505 0.5–1 E 0.6 H 0.705 0.8 0.86 1 1 1 1.5 1 1 1 1.005 2 2.5 3 3
t (°C) 21 25 25 20 25 25 ? 25 25 25 25 25 25 25 25 25 25 20 25 25 25 25 25 25 ? 25 25 25 25 25 25
log β110
log β120
log β130
log β140
log β13–1
log β12–2
log β10–1
References
6.2 – – 5.080 5.08 – 3.48 6.0 – – – – – – 4.21 – – 4.34 3.98 3.88 4.47 – – – – – – – – – –
10.9 – – 8.555 8.88 – 6.27 10.6 – – – – – – 7.5 – – 7.88 7.22 6.91 7.76 – – – – – – – – – –
13.4 – – 10.655 11.30 – 8.62 13.1 – – – – – – 9.88 – – 10.56 9.52 9.09 10.17 – – – – – – – – – (1.76)
16 11.29 – 11.557 12.18 11.81 9.72 – – – – 11.83 – – 11.32 – – 12.24 11.52 10.43 11.54 – – 11.78 (1.27) 12.15 – – – – (2.35)
– 6.29 2.04 A – – 6.43 – – 3.09 A 2.93 A – 5.64 2.85 A 2.86 A 2.37 F ~2.42 I 2.82 A – – – – – – 4.48 – – 2.82 A – – – –
– – – – – – – – – – – – – – –7.5 F –7.82 I – – – – – – – – – – – – – – –
– – – – – – – – – – –9.23 C – – – – – – – – – – –9.30 C –9.35 C – – – – –9.39 C –9.45 C –9.61 C –
[14] [19] [20] [21] [30] [19] [19] B [30] [29] [29] [16] D [19] [20] [29] [18] G [22] [29] [23] B [17] B [23] [15] [16] D [16] D [19] [30] [30] [29] [16] D [16] D [16] D [30]
log β140 from ref. [19] was used in calculations.
B
Literature values reported by authors.
C
Conditional formation constants with respect to palladium(II)–chloride species.
D
E
Further species reported by authors: –30.51 ≤ logβ40–4 ≤ –28.81 in the range 0.5 ≤ I (mol L–1) ≤ 3.0.
Only one value given by the authors in this ionic strength range.
At I = 0.7 mol L–1.
F
G
Other species reported by authors as recommended data: logβ11–3 = –17.65.
H
In mol kg–1.
I
logβpq0 from ref. [18] were used in calculations.
Page 2 of 3
Environ. Chem. 2010, 7, 259–267. doi:10.1071/EN10008_AC
©CSIRO 2010
Table A4. Literature values for palladium(II) hydrolysis and nitrate complexes in HNO3aq / NaNO3aq or HNO3aq / NaClO4aq at different temperatures and ionic strengths logβpqr refer to equilibrium: p Pd2+ + q NO3– + r H2O = Pdp(NO3)q(OH)r(2p–q–r) + r H+; ?, not specified I (mol L–1) ≤5 5.18 ? ? 4
t (°C) ? 25 ? ? ?
logβ110
logβ120
logβ130
logβ140
logβ11–1
References
0.08 0.17 1.14 0.51 0.2
– –0.76 0.3 0.32 –
– – 0.78 –0.65 –
– – – –2.40 –
– –0.64 – – –
[26] [27] [31] [31] [32]
100
% Pd
2+
80
+
2+
Pd(OH)
Pd
60
40
20
0 2
pH
3
Fig. A1. Distribution diagram of palladium hydrolytic species v. pH, at I = 0.1 mol L–1 in NaNO3aq at t = 25°C, obtained considering the conditional hydrolysis constants of Table 2. Experimental conditions: CPd = 1 mmol L–1.
Page 3 of 3
