Adsorption of Cu(II) and Zn(II) onto Activated Carbon from Oil Palm Empty Fruit Bunch Prepared by Two-Step Acid Treatment and Microwave-Assisted Pyrolysis

Table 1

Physical and chemical composition of adsorbents.

Item	Sample
	EFB	2ACEFB
BET surface area (m^2/g)	700.65	816.68
Pore volume (cm^3/g)	0.46	0.56
Pore size (Å)	32.16	22.43
Proximate analysis (wt%)
Moisture	4.82	6.15
Volatile	28.70	25.50
Fixed carbon	60.54	64.49
Ash	5.95	3.87
Ultimate analysis (wt%)
C	71.44	79.25
N	2.23	2.10
O	26.33	14.11
P	—	4.54

ASTM D7582-15 [17].