Characteristics of biochars derived from fruit tree pruning wastes and their effects on lead adsorption

Applied Biological Chemistry

Table 1 Physico-chemical characteristics of fruit tree pruning waste biochars under different pyrolysis temperatures

Content	Temperature (°C)	pH (1:25)	C (%)	H (%)	N (%)	S (%)	O (%)	T-P (%)	H/C	O/C	(O + N)/C	(O + N + S)/C	Yield (%)	SA (m² g⁻¹)
Pear	300	8.94	66.68	5.65	2.91	0.14	24.62	1.15	1.02	0.28	0.314	0.315	34.5	1.5
	400	9.29	69.58	4.73	3.21	0.11	22.63	1.40	0.82	0.24	0.280	0.281	26.4	3.6
	500	9.32	73.45	3.73	2.98	0.10	19.74	1.72	0.61	0.20	0.236	0.237	22.7	22.7
	600	10.08	75.09	3.52	2.95	0.10	18.34	2.00	0.56	0.18	0.217	0.217	20.3	134.2
Apple	300	8.51	67.34	5.70	2.98	0.27	23.71	0.74	1.02	0.26	0.302	0.304	36.5	2.2
	400	9.58	70.05	5.09	3.18	0.17	21.51	1.06	0.87	0.23	0.269	0.270	26.7	3.1
	500	9.82	77.16	4.02	2.71	0.13	15.98	1.37	0.63	0.16	0.185	0.186	23.6	13.6
	600	10.27	79.26	3.14	2.59	0.12	14.89	1.49	0.48	0.14	0.169	0.169	22.5	99.4
Persimmon	300	8.12	67.63	5.51	2.75	0.15	23.96	0.77	0.98	0.27	0.300	0.301	37.9	1.7
	400	9.55	71.12	4.66	3.06	0.20	20.96	1.13	0.79	0.22	0.258	0.259	29.2	2.9
	500	9.71	72.28	3.82	2.96	0.31	20.63	1.45	0.63	0.21	0.249	0.250	25.5	17.4
	600	9.89	76.87	2.85	2.71	0.18	17.39	1.63	0.45	0.17	0.200	0.201	22.3	114.1

H/C atomic ratio of hydrogen to carbon, O/C atomic ratio of oxygen to carbon, (O + N)/C atomic ratio of sum of nitrogen and oxygen to carbon, (O + N + S)/C atomic ratio of sum of nitrogen, oxygen and sulfur to carbon, SA BET-N₂ specific surface area