Removal of Lead (II) Ions from Aqueous Solutions onto Activated Carbon Derived from Waste Biomass

Table 4

Comparison of adsorption capacities of activated carbons obtained from various lignocellulosic materials for lead (II) ions.

Biomass	pH	𝑇 (K)	Operating conditions
			Initial concentration or range; (mg L^−1)	Amount of adsorbent; (g L^−1)	Adsorption capacity; (mg g^−1)
Apricot stone [7]	6.5	298.15	—	2.0	22.85
Soybean hulls [3]	5.0	296.15	518	10.0	39.37
Pecan shell [8]	4.8	—	104	0.5–10.0	64.2
Coconut shell [9]	5.6	298.15	—	2.0	76.66
Palm shell [10]	3.0 and 5.0	300.15	100–700	5.0	95.20
Sawdust [11]	5.0	300.15	50–1000	2.0	200.00
Bagasse pith [12]	4.0–8.0	303.15	100	—	200.00
Coir pith waste [13]	4.0	—	25–100	—	263.00
Euphorbia rigida [14]	5.0	313.15	50–200	0.8	279.72
Soybean oil cake*	5.5	298.15	50–500	0.5	476.2

∗Present study.