Table 1.

Elemental compositions, atomic ratio, surface area, micropore volume and pH of BCs before and after magnetic modification. BC, biochar; MBC, magnetic biochar; S_BET, surface area; V_p, micropore volume.

biochar samples	BC	MBC
SBET (m2 g−1)	52.1	109
Vp (cm3 g−1)	0.02	0.05
pH	9.08	8.55
pHpzc	4.32	3.71
C%	56.3	40.7
H%	2.05	1.65
O%	35.9	21.4
N%	0.71	0.47
S%	0.16	0.12
Fe%	—	8.49
O/C	0.48	0.39
H/C	0.44	0.49