Determination of five water-soluble anions in solid and liquid aerosols by ion chromatography with a filter membrane and condensation collection

doi:10.3724/SP.J.1123.2021.01007

Abstract

Abstract:

Water-soluble ions are important components of solid and liquid aerosols. The ions have a significant impact on the physical and chemical properties of the aerosols and air quality. Thus, determining the concentrations of water-soluble ions in solid and liquid aerosols has far-reaching significance for mitigating pollution and protecting the atmospheric environment. In this study, a technology combining membrane filtration, condensation, and ion chromatography has been established to collect solid aerosols and liquid aerosols and to measure the amount of five water-soluble anions (Cl^-, F^-, NO₃^-, NO₂^-, and SO₄^2-) in these aerosols. First, a solid particle filter was used to collect the solid aerosol, and the condensation collection method was used to collect the liquid aerosol. The solid aerosol was collected in the solid particle filter in the form of solid particles, and the liquid aerosol was collected in the cold trap in the form of a condensate. Next, the amount of water-soluble anions in the solid aerosols and liquid aerosols was detected by ion chromatography using Dionex IonPac AS11-HC-4 μm as the analytical column. The chromatographic separation conditions were as follows: flow rate, 1 mL/min; column temperature, 30 ℃; potassium hydroxide (KOH) concentration of the eluent, 1 to 25 mol/L (linear increase) within 0-40 min; and injection volume, 100 μL. The ions were separated effectively within 40 min. The five anions showed good linear relationships in the range of 0.1-10 mg/L (correlation coefficients ranged from 0.9992 to 0.9997) and the detection limits were 0.02-0.04 mg/L. Finally, the sample collection conditions (sampling time, sampling temperature, and sampling flow rate) for the five water-soluble anions in the solid aerosols and liquid aerosols were optimized, and 2 h, -13 ℃, 1.0 L/min were chosen.Under the optimized conditions, the amounts of the five anions in the solid and liquid aerosols of the actual samples were detected. The mass concentrations of F^-, Cl^-, NO₂^-, NO₃^-, and SO₄^2- ions in the liquid aerosol of the actual sample were 5.7402 μg/m³, 1.1599 μg/m³, 3.3233 μg/m³, 2.4861 μg/m³, and 0.9745 μg/m³, respectively. The mass concentrations of F^-, Cl^-, NO₂^-, NO₃^-, and SO₄^2- ions in the solid aerosol of the actual sample were 14.1037 μg/m³, 5.0398 μg/m³, 9.3052 μg/m³, 8.4528 μg/m³, and 5.6314 μg/m³, respectively. The method can be applied to the detection of actual atmospheric ions detection. In addition, the collection and analysis methods are suitable for exploring the collection and analysis conditions of other ions.

Key words: ion chromatography (IC), soluble ions, aerosols, condensation

CLC Number:

O658

YU Zuosi, LIU Yu, ZHU Yan. Determination of five water-soluble anions in solid and liquid aerosols by ion chromatography with a filter membrane and condensation collection[J]. Chinese Journal of Chromatography, 2022, 40(1): 82-87.

Figures/Tables 7

Fig. 1 Schematic of solid and liquid aerosol acquisition device

Table 1 Standard curves, linear ranges, correlation coefficients (r2), and LODs

Ion	Standard curve	Linear range/ (mg/L)	r²	LOD^*/ (mg/L)
F^-	y=0.9069x+0.0369	0.1-10	0.9997	0.02
Cl^-	y=0.8739x+0.0109	0.1-10	0.9992	0.02
N	y=0.4824x-0.0350	0.1-10	0.9993	0.04
N	y=0.6127x-0.0046	0.1-10	0.9996	0.03
S	y=0.6992x-0.0226	0.1-10	0.9995	0.04

Fig. 2 C1-C4 at different collection times (n=5) C1: water-soluble ion mass in condensate of liquid aerosol; C2: C1/V0 (V0 is atmosphere volume at standard state); C3: water-soluble ion mass in soak solution of solid aerosols; C4: C3/V0.

Fig. 3 C1-C4 under different collection flows (n=5)

Fig. 4 C1 and C2 at different collection temperatures (n=5)

Fig. 5 Chromatograms of an actual sample

Table 2 C2, C4, and their RSDs of actual samples (n=5)

Ion	C₂/(μg/m³)	C₂ RSD/%	C₄/(μg/m³)	C₄ RSD/%
F^-	5.7402	4.5	14.1037	3.8
Cl^-	1.1599	4.1	5.0398	4.2
N	3.3233	3.6	9.3052	4.4
N	2.4861	3.9	8.4528	3.6
S	0.9745	3.7	5.6314	3.9

References

[1]	Xin J Y, Gong C S, Wang S G, et al. Atmos Res, 2016, 171: 56
[2]	Tian S L, Pan Y P, Wang Y S. Atmos Chem Phys, 2016, 16(1): 1
[3]	Shi C E, Deng X L, Zhu B, et al. Acta Meteorologica Sinica, 2016, 74(1): 149
[3]	石春娥, 邓学良, 朱彬, 等. 气象学报, 2016, 74(1): 149
[4]	Shi Y Z, An J L, Wang H L, et al. Environmental Science, 2016, 37(12): 4475
[4]	师远哲, 安俊琳, 王红磊, 等. 环境科学, 2016, 37(12): 4475
[5]	Li Q F, Wang L L, Jayanty R K M, et al. Open J Air Pollut, 2013, 2(1): 7
[6]	Chueinta W, Hopke P K, Paater O P. Atmos Environ, 2000, 34(20): 3319
[7]	Kan H D, Chen R J, Tong S L. Environ Int, 2012, 42: 1
[8]	Hua Y, Cheng Z, Wang S X, et al. Atmos Environ, 2015, 123: 380
[9]	Yang D Y, Liu B X, Zhang D W, et al. Environmental Science, 2015, 36(12): 4325
[9]	杨懂艳, 刘保献, 张大伟, 等. 环境科学, 2015, 36(12): 4325
[10]	Zhou J J, Shi J H, Li L P, et al. Environmental Science, 2015, 36(9): 3135
[10]	周佳佳, 石金辉, 李丽平, 等. 环境科学, 2015, 36(9): 3135
[11]	Wang L, Wen T X, Miao H Y, et al. Environmental Science, 2016, 37(9): 3249
[11]	王璐, 温天雪, 苗红妍, 等. 环境科学, 2016, 37(9): 3249
[12]	Fang Y, Cao F, Fan M Y, et al. Environmental Science, 2020, 41(3): 1025
[12]	方言, 曹芳, 范美益, 等. 环境科学, 2020, 41(3): 1025
[13]	Hou Z X, Bi W, Zhao C F, et al. Environmental Science and Management, 2019, 44(7): 48
[13]	侯忠新, 毕玮, 赵长芳, 等. 环境科学与管理, 2019, 44(7): 48
[14]	Zhang C, Yu X N, An J L, et al. China Environmental Science, 2018, 38(8): 2873
[14]	张程, 于兴娜, 安俊琳, 等. 中国环境科学, 2018, 38(8): 2873
[15]	Lei T Y, Zang Y, Gao Y G, et al. Research of Environmental Sciences, 2020, 33(4): 831
[15]	雷天阳, 藏雨, 高元官, 等. 环境科学研究, 2020, 33(4): 831
[16]	Dao X, Zhang L L, Wang C, et al. Environmental Science, 2015, 34(1): 61
[16]	刀谞, 张霖琳, 王超, 等. 环境科学, 2015, 34(1): 61
[17]	Zhao K L, Liu X C, Lu H, et al. Journal of Desert Research, 2015, 35(3): 707
[17]	赵克蕾, 刘新春, 陆辉, 等. 中国沙漠, 2015, 35(3): 707
[18]	Jiang L, Zhu B, Wang H L, et al. China Environmental Science, 2017, 37(10): 3601
[18]	蒋琳, 朱彬, 王红磊, 等. 中国环境科学, 2017, 37(10): 3601