Humic Acid, Kerogen, and Black Carbon Isolated from Atmospheric Total Suspended Particulate from Guangzhou, China

Figures & data

Figure 1 The isolation flow chart of humic acids, kerogen and black carbon, and black carbon. To reduce manipulation steps and achieve quantitative isolation of macromolecular fractions, the procedure was split into A and B. For detailed procedure, see the online supplementary information.

Table 1 TC, relative contents of organic fractions, and elemental (C, H, N) compositions

Sampling				Elementary composition and atomic ratios
Sites	Seasons	Fractions	Contents %	C%	H%	N%	H/C^5	N/C^5
WS	Summer	DOC^1	18.8
		HA	2.90	70.5 ± 1.3^4	5.70 ± 0.10	2.79 ± 0.37	0.96	0.03
		KB	53.6	44.3 ± 0.2	1.43 ± 0.00	0.30 ± 0.04	0.39	0.01
		BC	21.5	81.4 ± 0.7	0.86 ± 0.01	0.47 ± 0.23	0.13	0.00
		K^2	32.1	19.5	1.81	0.19	1.11	0.01
		TC^3	17.6
WS	Winter	DOC	28.5
		HA	2.39	66.4 ± 0.8	5.67 ± 0.02	3.33 ± 0.24	1.03	0.04
		KB	50.7	46.0 ± 0.1	2.18 ± 0.11	0.54 ± 0.03	0.57	0.01
		BC	27.0	79.0 ± 0.7	1.86 ± 0.03	0.82±0.14	0.28	0.01
		K	23.6	8.36	2.55	0.22	3.65	0.02
		TC	14.5
UT	Summer	DOC	22.0
		HA	5.51	72.6 ± 1.4	5.10 ± 0.20	2.78 ± 0.72	0.85	0.03
		KB	44.3	44.3 ± 0.1	0.70 ± 0.00	0.28 ± 0.01	0.18	0.01
		BC	24.3	71.8 ± 0.2	0.52 ± 0.02	0.27 ± 0.02	0.09	0.00
		K	20.0	10.7	0.87	0.29	0.98	0.02
		TC	15.7
UT	Winter	DOC	24.9
		HA	3.46	67.7 ± 0.4	6.37 ± 0.01	4.48 ± 0.34	1.13	0.06
		KB	40.5	41.8 ± 0.0	1.83 ± 0.02	0.68 ± 0.07	0.53	0.01
		BC	16.1	79.3 ± 1.9	1.44 ± 0.06	0.38 ± 0.10	0.22	0.00
		K	24.4	17.0	2.09	0.88	1.47	0.04
		TC	12.8
MF	Summer	DOC	36.5
		HA	4.60	74.0 ± 0.5	5.84 ± 0.01	4.82 ± 0.03	0.95	0.06
		KB	37.4	49.4 ± 0.1	1.73 ± 0.01	1.00 ± 0.06	0.42	0.02
		BC	21.4	73.2 ± 0.3	1.85 ± 0.04	0.38 ± 0.01	0.30	0.00
		K	16.0	17.42	1.57	1.83	1.08	0.09
		TC	17.0
MF	Winter	DOC	40.3
		HA	14.8	71.6 ± 1.4	4.99 ± 0.45	2.17 ± 0.52	0.84	0.03
		KB	48.7	44.8 ± 0.2	1.28 ± 0.03	0.28 ± 0.04	0.34	0.01
		BC	21.1	72.7 ± 0.7	0.69 ± 0.13	0.27 ± 0.01	0.11	0.00
		K	27.5	23.3	1.73	0.29	0.89	0.01
		TC	19.0

¹Percentage weight of dissolved organic carbon was measured first instrumentally (TNM-1, Shimadzu Co. Ltd., Japan) and followed by calculation of the average values of two runs.²Percentage weight in TC: elemental composition and atomic ratios of K were calculated based on KB and BC data, average values of two runs.³Percentage weight of TC means organic carbon content in TSP, average values of two runs. Others are percentage weight in TC.⁴Average values ± SD in EA analyses.⁵Atomic ratio.

Figure 2 Relative contents (%) of DOCs, HAs, K, and BCs in total carbon of TSPs from the air of Guangzhou. Recovery is the sum of percentage of these four fractions. WS-Summer labels are the site followed by the season the sample was collected in.

Table 2 Percentage of carbon groups in the solid ¹³C NMR spectra

Sample	Alkyl carbons 0–50 ppm	Methoxyl carbons 50–60 ppm	Hydroxyl carbons 60–90 ppm	Alkyl-substituted aromatic carbons 110–130 ppm	Oxygen-substituted aromatic or phenolic carbons 130–160 ppm	Carboxylic carbons 160–188ppm	Carbonyl carbons 188–230ppm	Aromaticity^1 (%)
WS-S-KB^2	48.4	8.81	4.06	4.40	28.9	2.42	0	36.8
WS-S-BC	57.0	5.27	3.22	0.00	31.3	3.22	0	34.6
WS-W-BC	23.5	6.76	4.70	0	37.3	21.4	7.30	62.7
UT-W-KB	44.4	2.47	24.4	3.42	19.0	1.90	4.38	25.5
UT-W-BC	30.9	2.31	10.2	0.00	41.2	14.4	1.96	56.1

¹Aromaticity (%) = [aromatic C (106–150 ppm)+carboxylic C (151–170 ppm)]/[aromatic C+ carboxylic C+ aliphatic C (0–105 ppm)]×100.²WS-S-KB: Naming is site followed by season the samples were collected in.

Figure 3 The typical CP/MAS ¹³C NMR spectra of KB and BC isolated from the TSP.

Figure 4 FTIR spectra of the isolated fractions from the TSP collected in MF in winter. For sample nomenclature, see Table 2.

Figure 5 Crossplot of f_biogenic vs. δ¹³C values for fractions of HA, KB, K, and BC. (Color figure available online.)

Table 3 Δ¹⁴C(‰) of macromolecular organic matters in TSP and the contribution of contemporary carbon (f_biogenic)

Samples	Δ^14C(‰)	fbiogenic (%)
MF-S-HA	−415.54 ± 1.67	46.87 ± 0.15
MF-S-KB	−125.12 ± 1.09	20.47 ± 0.10
MF-S-BC	0.92 ± 0.60	9.01 ± 0.05
MF-S-K		37.63
MF-W-HA	−573.58 ± 2.26	61.23 ± 0.21
MF-W-KB	−93.45 ± 1.30	17.59 ± 0.12
MF-W-BC	−89.31 ± 1.41	17.21 ± 0.13
MF-W-K		18.76
UT-S-HA	−386.54 ± 1.70	44.23 ± 0.15
UT-S-KB	−92.51 ± 0.93	17.50 ± 0.08
UT-S-BC	−7.35 ± 1.02	9.76 ± 0.09
UT-S-K		28.73
UT-W-HA	−486.65 ± 2.12	53.33 ± 0.19
UT-W-KB	−152.06 ± 1.60	22.91 ± 0.15
UT-W-BC	63.75 ± 0.37	3.30 ± 0.03
UT-W-K		37.64
WS-S-HA	−530.57 ± 2.20	57.32 ± 0.20
WS-S-KB	−173.06 ± 1.33	24.82 ± 0.12
WS-S-BC	−41.24 ± 0.77	12.84 ± 0.07
WS-S-K		34.46
WS-W-HA	−575.93 ± 2.10	61.45 ± 0.19
WS-W-KB	−112.11 ± 1.03	19.28 ± 0.12
WS-W-BC	23.48 ± 0.50	6.96 ± 0.05
WS-W-K		35.06

For the sample's nomenclature see Table 2.