Table 1.

Phosphorus (P) adsorption capacity of activated biochars derived from various feedstocks.

Feedstock	P Form	Activation	Carbonization	Adsorption	References
		Agents	Activation	Capacity
			Conditions	mg g−1
			(°C)	qmax
Peanut shells	P	1 M MgCI2	600	18.9	[94]
Poplar chips	PO4−3	4% MgCI2	600	89.9	[87]
Soybean straw	PO4−3	2 M MgCI2	500	74.5	[82]
Ground coffee
waste	P	3 M MgCI2	500	56	[88]
Sewage sludge+
dolomite, 1:1	PO4−3	Dolomite	800	29.2	[83]
Banana straw	P	1 M MgCI2	430	31.2	[95]
Wheat straw	PO4−3	0.5 M MgCI2+
		0.5 M AICI3	600	153.4	[96]
Dairy manure	PO4−3	2 M CaCI2	500	13.6	[97]
Crop residuals	P	3.1 M MgCI2	600	65.4	[98]
Tea residuals	PO4−3	0.001 M AgNO3	400	13.6	[99]