Equilibrium, Kinetics, and Thermodynamics of the Removal of Nickel(II) from Aqueous Solution Using Cow Hooves

Table 3

FTIR spectral characteristics of CH before and after Ni (II) removal.

IR peak	Frequency (cm^−1); before adsorption	Frequency (cm^−1); after adsorption	Difference	Functional group
1	3314.00	—	—	Bonded –OH group
2	2931.42	2942.85	11.43	Aliphatic C–H groups
3	2365.71	2354.28	−11.43	S–H stretching
4	1658.60	1652.33	−6.27	C=O stretching
5	1530.58	1526.94	−3.64	Amino/nitro compound
6	1393.00	1387.30	−5.70	Nitro compound
7	1239.11	1233.41	−5.70	C–N stretching
8	1039.63	1056.73	17.10	C–O stretching