Comparison on the Surface Structure Properties along with Fe(II) and Mn(II) Removal Characteristics of Rice Husk Ash, Inactive Saccharomyces cerevisiae Powder, and Rice Husk

Table 4

Thermodynamic parameters for Fe(II) and Mn(II) adsorption on three adsorbents.

Metal ion	Adsorbent	(kJ/mol)			(J/mol)	(J/mol K)
		303 K	313 K	323 K
Fe(II)	RHA	−2.81	−2.63	−2.30	−40.94	−15.49
	ISP	−2.34	−1.43	−0.69	−95.49	−31.46
	RH	−3.77	−2.97	−2.42	−88.80	−30.99
Mn(II)	RHA	−2.89	−2.50	−2.30	−12.92	−6.60
	ISP	−2.43	−1.24	−0.78	−83.73	−27.69
	RH	−2.52	−2.26	−1.69	−40.74	−14.91

Note. The three adsorbents include the following: rice husk ash, RHA; inactive Saccharomyces cerevisiae powder, ISP; rice husk, RH.