Chemical composition of the CSB and Fe-CSB.

Item	Fe	Al	Ca	Mg	TP	C (%)	H (%)	O (%)	N (%)	H/C	O/C	(O + N)/C
	(mg g−1)
CSB	1.61	2.36	5.1	2.65	0.13	84.31	1.42	13.54	0.48	0.02	0.16	0.17
Fe-CSB	106.6	0.78	3.44	0.86	0.11	28.89	5.28	32.18	0.42	0.18	1.11	1.13