Geochemical Association of Ni ²⁺ , Zn ²⁺ , Pb ²⁺ , Ag ⁺ , Cu ²⁺ , and Co ²⁺ Ions in Natural Pyrite

Table 4

Thermodynamic parameters for metal ion adsorption in binary systems.

Metal ion	In presence of	pH 4			pH 5			pH 6			pH 7			pH 8
		−Δ𝐺×10^2; J mol^−1	Δ𝑆×10^−2; J K^−1 mol^−1	−Δ𝐻×10^2; J mol^−1	−Δ𝐺×10^2; J mol^−1	Δ𝑆×10^−2; J K^−1 mol^−1	−Δ𝐻×10^2; J mol^−1	−Δ𝐺×10^2; J mol^−1	Δ𝑆×10^−2; J K^−1 mol^−1	−Δ𝐻×10^2; J mol^−1	−Δ𝐺×10^2; J mol^−1	Δ𝑆×10^−2; J K^−1 mol^−1	−Δ𝐻×10^2; J mol^−1	−Δ𝐺×10^2; J mol^−1	Δ𝑆×10^−2; J K^−1 mol^−1	−Δ𝐻×10^2; J mol^−1
Ni^2+	Zn^2+	87.06	27.25	86.24	88.16	27.20	87.34	92.02	26.21	91.23	104.81	21.11	104.17	122.36	15.88	121.88
	Pb^2+	83.64	21.56	82.99	85.60	21.33	84.96	86.43	21.15	85.79	95.93	18.92	95.36	113.86	17.31	113.34
	Ag^+	83.45	23.96	82.72	88.39	22.53	87.71	91.25	21.68	90.60	95.33	21.14	94.69	100.52	20.71	99.90
	Cu^2+	85.19	24.52	84.46	85.80	24.28	85.07	92.54	20.69	91.92	113.26	17.35	112.74	141.55	16.20	141.06
	Co^2+	85.60	24.03	84.87	86.22	24.15	85.49	87.06	23.95	86.34	100.52	21.54	99.87	122.36	19.07	121.79
Zn^2+	Ni^2+	67.19	27.25	66.37	66.78	27.20	65.96	69.48	26.21	68.69	93.62	21.11	92.99	207.73	15.88	207.25
	Pb^2+	67.83	24.74	67.08	67.19	24.31	66.46	67.61	23.90	66.89	93.35	18.99	92.78	207.73	15.52	207.26
	Ag^+	66.37	27.20	65.55	66.98	26.43	66.19	70.99	24.89	70.24	180.20	17.69	179.67	ND	18.97	ND
	Cu^2+	64.69	28.30	63.84	64.50	28.19	63.65	67.61	23.90	66.89	103.57	18.03	103.02	207.73	15.52	207.26
	Co^2+	64.22	28.73	63.35	64.50	28.72	63.64	67.83	27.73	66.99	122.36	19.48	121.77	ND	15.97	ND
Pb^2+	Ni^2+	123.22	21.56	122.57	122.36	21.33	121.72	124.10	21.15	123.46	180.20	18.92	179.63	ND	17.31	ND
	Zn^2+	113.26	24.74	112.52	124.10	24.31	123.37	132.58	23.90	131.86	ND	18.99	ND	ND	15.52	ND
	Ag^+	132.58	19.34	131.99	135.23	19.74	134.64	ND	16.82	ND	ND	17.80	ND	ND	17.24	ND
	Cu^2+	130.18	20.93	129.55	125.97	20.99	125.34	ND	15.64	ND	ND	ND	ND	ND	ND	ND
	Co^2+	123.22	21.22	122.58	127.99	20.94	127.36	167.39	20.26	166.78	ND	17.49	ND	ND	17.28	ND
Ag^+	Ni^2+	91.50	23.96	90.78	99.12	22.53	98.45	105.24	21.68	104.58	106.56	21.14	105.93	105.67	20.71	105.05
	Zn^2+	88.84	27.20	88.02	94.46	26.43	93.67	102.77	24.89	102.02	111.01	17.69	110.47	119.95	18.97	119.38
	Pb^2+	100.17	19.34	99.58	95.04	19.74	94.44	123.22	16.82	122.71	106.56	17.80	106.03	115.09	17.24	114.57
	Cu^2+	97.16	22.88	96.47	103.57	22.29	102.89	112.68	17.84	112.14	107.96	17.77	107.43	112.11	17.24	111.58
	Co^2+	95.04	23.04	94.34	99.12	22.67	98.44	107.96	21.39	107.32	158.95	17.91	158.41	111.55	19.21	110.97
Cu^2+	Ni^2+	84.99	24.52	84.26	86.22	24.28	85.49	118.47	20.69	117.84	ND	17.35	ND	ND	16.20	ND
	Zn^2+	83.07	28.30	82.22	84.21	28.19	83.36	132.58	23.90	131.86	ND	18.03	ND	ND	15.52	ND
	Pb^2+	86.22	20.93	85.59	87.06	20.99	86.43	180.20	15.64	179.73	ND	ND	ND	ND	ND	ND
	Ag^+	87.06	22.88	86.37	87.28	22.29	86.61	155.60	17.85	155.07	207.73	17.77	207.19	ND	17.42	ND
	Co^2+	85.40	24.84	84.65	87.50	24.44	86.76	207.73	19.66	207.14	ND	19.40	ND	ND	17.60	ND
Co^2+	Ni^2+	88.39	24.03	87.66	86.85	24.15	86.12	87.50	23.95	86.78	96.23	21.54	95.58	108.44	19.07	107.87
	Zn^2+	80.77	28.73	79.90	80.43	28.74	79.56	82.52	27.73	81.69	103.17	19.48	102.58	152.65	15.97	152.17
	Pb^2+	86.22	21.22	85.58	86.85	20.94	86.22	85.40	20.26	84.79	111.01	17.49	110.48	114.47	17.28	113.95
	Ag^+	87.50	23.04	86.80	87.28	22.67	86.60	92.02	21.39	91.37	111.01	17.91	110.47	115.73	19.21	115.15
	Cu^2+	82.52	24.84	81.77	83.45	24.44	82.71	88.16	19.66	87.57	89.78	19.40	89.20	109.44	17.60	108.91

ND: not determinable.