Optimization of carbon extraction from water by wet oxidation

被引：0

作者：

Li L. ^{[1
,2
]}

Liu W. ^{[2
]}

Ma Y. ^{[2
]}

Li Z. ^{[1
]}

Deng K. ^{[2
]}

Zeng L. ^{[2
]}

Xu Y. ^{[1
]}

机构：

[1] Hengyang Normal University, Hengyang

[2] Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai

来源：

He Jishu/Nuclear Techniques | 2024年 / 47卷 / 03期

关键词：

!sup]14[!/sup]C in water; Inorganic carbon; Organic carbon; Ultraviolet; Wet oxidation;

D O I：

10.11889/j.0253-3219.2024.hjs.47.030303

中图分类号：

学科分类号：

摘要：

[Background] Extraction of carbon from water is a crucial preprocessing step for measuring 14C in environmental waters using liquid scintillation spectrometry. [Purpose] This study aims to explore the optimal technological conditions for extracting carbon from water using wet oxidation method. [Methods] A wet oxidation system combining sodium persulfate and Fenton's reagent, along with phosphoric acid acidification and nitrogen bubbling, were employed for the wet oxidation carbon extraction experiments on two types of water samples with known (deionized water + sucrose) and unknown carbon components, each with a volume of 10 L. Simultaneously, carbon extraction experiments were conducted on the water samples having unknown carbon component, using a combination of wet oxidation and 185 nm ultraviolet (UV) oxidation so as to determine the optimal timing and sequence of reagent addition, as well as the optimized reagent dosage and ratio. Further experiments under optimized conditions were conducted to obtain more results for deep analysis. [Results] Under the optimized conditions, after a 3-h reaction at 90 °C, the organic carbon extraction rate for the known carbon component (deionized water + sucrose) exceeds 96%. The total carbon extraction rate from the unknown carbon component water is (96.8±0.3)%, with an inorganic carbon extraction rate >98.5%, and an organic carbon extraction rate of (93.4±0.2)%, while the oxidation rate of tannic acid-type organic compounds is only (88±0.2)%. After the combination of wet oxidation and 185 nm UV oxidation, the total carbon extraction rate for the unknown carbon component increases to (98.3±0.5)%, with an inorganic carbon extraction rate ≥99% and an organic carbon extraction rate that can reach (95.6±1.4)% . [Conclusions] Results of this study indicate that wet oxidation alone cannot represent the carbon recovery rate in actual water samples using typical organic compound carbon recovery rates. The combination of wet oxidation and 185 nm UV oxidation proves to be a more effective method for carbon extraction from water. © 2024 Science Press. All rights reserved.

引用

共 22 条

[1] ZHEN Liying, ZHANG Jiajun, LIN Yinghui, Et al., Analysis of the accuracy of 14C in gaseous effluent of nuclear power plant by direct measurement method, Nuclear Techniques, 45, 9, (2022)
[2] HUANG Yanjun, SHA Xiangdong, ZHU Zhaowen, Et al., Study on key nuclides of effluent monitoring in pressurized water reactor nuclear power plant[J], Nuclear Safety, 19, 5, pp. 27-34, (2020)
[3] Zhang G Q, Wang S, Zhang H Q, Et al., Radionuclides in primary coolant of a fluoride salt-cooled high-temperature reactor during normal operation, Nuclear Science and Techniques, 28, 3, (2017)
[4] Zhao C, Wang G, Zhang M, Et al., Transport and dispersion of tritium from the radioactive water of the Fukushima Daiichi nuclear plant, Marine Pollution Bulletin, 169, (2021)
[5] Feng B, Zhuo W H., Levels and behavior of environmental tritium in East Asia, Nuclear Science and Techniques, 33, 7, (2022)
[6] Stojkovic I, Todorovic N, Nikolov J, Et al., Investigation of fast screening LSC method for monitoring 14C activity in wastewater samples[J], Radiation Measurements, 121, pp. 1-9, (2019)
[7] GUO Guiyin, HUANG Yanjun, ZHANG Bing, Et al., Analysis of 14C in environmental water based on wet-oxidation pretreatment[J], Radiation Protection, 35, 6, pp. 339-344, (2015)
[8] Molnar A, Molnar M, Veres M, Et al., Determination of the total 14C concentration of water samples using the COD method and AMS[J], Radiocarbon, 64, 5, pp. 1065-1074, (2022)
[9] MENG Liping, BAO Li, YANG Hailan, Et al., Preparation and analysis of radiocarbon in water sample[J], Environmental Science and Management, 42, 8, pp. 139-142, (2017)
[10] Yoon G, Park S M, Yang H, Et al., Selection criteria for oxidation method in total organic carbon measurement[J], Chemosphere, 199, pp. 453-458, (2018)

← 1 2 3 →