JOURNAL OF HAZARDOUS MATERIALS
·
2024
·
IF 12.2
Qian Guo,Dongmei Yu,Jing Yang,Ting Zhao,Dan Yu,Lei Li,Duanjie Wang
The distribution characteristics of Cr(VI) species in contaminated soil is crucial for soil remediation; however, there is currently a lack of methods for analysing anionic Cr(VI) species in soil. This study has developed a novel sequential extraction method for speciation of Cr(VI) and Cr(III). Besides extraction experiments, simulated chromium species were prepared to verify the presence of proposed chromium species. The results show that Cr(VI) species in soil can be categorized into water-soluble Cr(VI), electrostatically adsorbed Cr(VI), Cr(VI) specifically adsorbed by minerals containing exchangeable Ca 2+ , Cr(VI) specifically adsorbed by hydrous metal oxides, calcium chromate Cr(VI) and stable complexed adsorption Cr(VI). These Cr(VI) species can be selectively extracted by specific solutions through ion exchange or weak acid dissolution. The most stable Cr(VI) species is Cr(VI) complexed by hydrous iron oxides through bidentate ligand binding; only by dissolution of hydrous iron oxides can this Cr(VI) species be leached. The distribution of Cr(VI) species is closely linked to particular soil compositions including exchangeable Ca 2+ and hydrous iron oxides which determinate the Cr(VI) adsorption in soil. Cr(III) species comprise Fe-Cr coprecipitate hydroxides Cr(III), Fe-Mn oxide-bound Cr(III), organic matter-bound Cr(III) and residual Cr(III). Their distribution depends on the types of reductants present in the soil.
研究领域:
环境科学
·
土壤化学
✓ 已验证
DOI
PubMed
高影响因子
Scientific Reports
·
2018
·Vol. 8
·期 1
·1-14
·
IF 4.122
Huang Wenli,Jiao Jie,Ru Mei,Bai Zhenqing,Yuan Honglin,Bao Zhian,Liang Zongsuo
Coptis chinensis Franch. is one of the most important medicinal plants globally. However, this species contains relatively high concentrations of chromium (Cr) which potentially detrimental to human health. It is important to understand Cr localization and speciation in order to evaluate its accumulation and transportation mechanisms and minimize Cr transfer to humans. As little previous work in this area has been carried out, we utilized synchrotron radiation microscopic X-ray fluorescence (SR-μXRF) and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) to spatially locate Cr, X-ray absorption near-edge spectroscopy (XANES) to analyze Cr speciation, and inductively coupled plasma mass spectrometry (ICP-MS) to detect Cr subcellular concentration. Micromapping results showed that Cr was distributed predominantly within the vascular cylinder, the periderm and some outer cortex, and the cortex and some vascular bundles in root, rhizome, and petiole, respectively. XANES data showed that Cr(VI) can be reduced to Cr(III) when grown with Cr(VI), and yielded a novel conclusion that this plant contain elemental chromium. ICP-MS data showed that Cr was primarily compartmentalized in cell walls in all tissues. The new insights on Cr accumulation in C. chinensis Franch. provide a theoretical basis for the evaluation of Cr in other medicinal plants.
研究领域:
植物学
·
环境科学
·
药用植物研究
✓ 已验证
DOI
高影响因子
TALANTA
·
2021
·
IF 6.057
Hui-Min Zhai,Bin Ji,Shan-Shan Tian,Fang Fang,Shuang Zhao,Zhi-Yong Wu
This work presents a new method of Cr speciation analysis based on micro sample pretreatment with a paper-based analytical device (PAD). By using electrokinetic separation and stacking on the PAD, Cr (VI) and Cr (III) can be separated and the recovered to achieve speciation analysis without have to be subjected to subtraction treatment. The separation and recovery properties of Cr (VI) and Cr (III) were characterized and optimized by UV–Vis spectrophotometry , with which the LOQ of 19.0 μg L −1 and 28.7 μg L −1 , and the recoveries of 88–108% and 90–110%, were obtained for Cr (VI) and Cr (III), respectively. In addition, direct analysis of Cr (VI)/Cr (III) from an electroplating wastewater sample was also demonstrated with this method combined with atomic spectroscopy (GF-AAS and ICP-OES). This sample pretreatment method is fast, cheap and easy to be used. Combined with the high sensitivity and elemental selectivity of atomic spectroscopy and mass spectrometry, this PAD sample pretreatment method could be a compensation to their lack in speciation discrimination, and may play an important role in the speciation analysis of Cr.
研究领域:
分析化学
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MOLECULES
·
2025
·Vol. 30
·期 15
·3076
·
IF 4.6
Shuai Zhu,Junru Chen,Yun Zhu,Baoke Zhang,Jing Jia,Meng Pan,Zhipeng Yang,Jianhua Cao,Yating Shen
Chromium slag sites pose severe environmental risks due to hexavalent chromium (Cr(VI)) contamination, characterized by high mobility and toxicity. This study focused on chromium-contaminated soil from a historical chromium slag site in North China, where long-term accumulation of chromate production residues has led to serious Cr(VI) pollution, with Cr(VI) accounting for 13–22% of total chromium and far exceeding national soil risk control standards. To elucidate Cr(VI) transformation mechanisms and elemental linkages, a combined approach of macro-scale condition experiments and micro-scale analysis was employed. Results showed that acidic conditions (pH < 7) significantly enhanced Cr(VI) reduction efficiency by promoting the conversion of CrO42−to HCrO4−/Cr2O72−. Among reducing agents, FeSO4exhibited the strongest effect (reduction efficiency >30%), followed by citric acid and fulvic acid. Temperature variations (−20 °C to 30 °C) had minimal impact on Cr(VI) transformation in the 45-day experiment, while soil moisture (20–25%) indirectly facilitated Cr(VI) reduction by enhancing the reduction of agent diffusion and microbial activity, though its effect was weaker than chemical interventions. Soil grain-size composition influenced Cr(VI) distribution unevenly: larger particles (>0.2 mm) in BC-35 and BC-36-4 acted as main Cr(VI) reservoirs due to accumulated Fe-Mn oxides, whereas BC-36-3 showed increased Cr(VI) in smaller particles (<0.074 mm). μ-XRF and correlation analysis revealed strong positive correlations between Cr and Ca, Fe, Mn, Ni (Pearson coefficient > 0.7,p< 0.01), attributed to adsorption–reduction coupling on iron-manganese oxide surfaces. In contrast, Cr showed weak correlations with Mg, Al, Si, and K. This study clarifies the complex factors governing Cr(VI) behavior in chromium slag soils, providing a scientific basis for remediation strategies such as pH adjustment (4–6) combined with FeSO4addition to enhance Cr(VI) reduction efficiency.
研究领域:
环境科学
·
土壤化学
·
污染控制
·
地球化学
·
环境修复
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）