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Fabrication of magnetic ordered mesoporous carbon for quantitative analysis of acidic phytohormones in mushroom samples prior to their determination by ultra-high-performance liquid chromatography–tandem mass spectrometry

Zhang Qianchun, Chen Yan, Yang Yanqun, Liu Yulan, Wen Ming, Wang Xingyi

Acta Chromatographica

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2023

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Vol. 35, no. 1

60--69

EN

A novel method was established for analysing trace four acidic phytohormones, namely, indole-3-acetic acid, 3-indolebutyric acid, abscisic acid, and 1-naphthylacetic acid, using magnetic ordered mesoporous carbon (MOMC). MOMC was facilely synthesised via self-assembly strategy with a direct carbonisation process. The properties of MOMC were characterised using various instruments. MOMC exhibited excellent adsorption capacity towards the analytes. Various critical parameters which may influence the enrichment efﬁciency were evaluated, including amount of MOMC, extraction conditions, and desorption conditions. An efficient method based on MOMC magnetic solid-phase extraction coupled with ultra-high-performance liquid chromatography–tandem mass spectrometry (UHPLC–MS/MS) was developed to analyse the trace four acidic phytohormones, with good correlation coefﬁcients (R2 = 0.9965–0.9998) and low limits of detection (0.13–9.7 ng L⁻¹, S/N = 3). Trace acidic phytohormones in Agaricus bisporus and Hypsizygus marmoreus samples were determined with satisfactory recoveries (91.8–108%) and reproducibility (2.6–6.3%). The features indicated that MOMC provides an efficient platform for mushroom sampling; the developed method is convenient, promising, and sensitive for the detection of trace phytohormones in complicated mushroom samples.

2

Study on fluoride fixation effect of Bayan Obo rare earth iron ore and three sodium agents under microwave irradiation

Guo Jing, Wen Ming, Li Jie, Hong Xunhai, Zhang Wenhao, Wang Yonglun

Physicochemical Problems of Mineral Processing

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2022

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Vol. 58, iss. 1

63--76

EN

To investigate the fluorine fixation of Bayan Obo rare-earth iron ores in beneficiation and metallurgy processes, the effect of three sodium agents, namely, sodium hydroxide, sodium carbonate, and sodium bicarbonate, on fluorine fixation under the action of microwaves was investigated using Xray diffraction, chemical detection, and orthogonal experiments. The effects of different types of sodium, roasting temperatures, sodium ratios, and roasting times on the fluorine fixation rate were evaluated. Results show that compared with conventional roasting, the fluorine fixation efficiency of Bayan Obo rare-earth iron ore under the action of microwave is superior after the formulation of the sodium agent, which is crucial for the study. Among the three sodium agents, the fluorine fixation effect of NaHCO3 can be used as the preferred sodium agent. Orthogonal experiments showed that the factors influencing the magnitude of the fluorine fixation rate are the roasting temperature, sodium agent ratio, and roasting constant temperature time in the order of priority. The optimal conditions for the fluorine fixation process are the microwave roasting temperature of 973.15 K, sodium bicarbonate ratio of 40%, and roasting time of 60 min. The highest fluorine fixation rate of 86.72% can be obtained. The findings of this study can provide a reference for the development of green and economic recovery processes for Bayan Obo rare-earth iron ores.

3

Mechanistic study on the flotation of barite with C18H33NaO2 under microwave radiation based on UV-visible spectrophotometric analysis

Guo Jing, Wen Ming, Wu Jingxuan

Physicochemical Problems of Mineral Processing

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2022

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Vol. 58, iss. 6

art. no. 156349

EN

Based on the pure mineral flotation tests of barite, this study investigated the effect law of microwave on barite flotation by using a UV-visible spectrophotometer (L5), solution chemistry calculation, and zeta potential, scanning electron microscope (SEM), and other testing methods. Additionally, red flotation kinetic analysis was carried out to deeply explore the mechanism of C18H33NaO2 flotation of barite under microwave radiation. Mineral flotation tests showed that after microwave treatment, the flotation recovery of barite and deionized water increased by 2.67% and 3.35%, respectively, while that of the microwave action pulp and chemically added pulp decreased by 2.90% and 8.51%, respectively. Microwave action on barite can improve its flotation recovery (up to 95.27%). The action of microwave heating can improve the positive electrical properties of the surface of barite, and accordingly, its specific surface area would be enlarged. In this case, the adsorption rate of sodium oleate on the surface of barite increased, thereby improving the flotation recovery. The flotation kinetics analysis revealed that the k-value of the primary kinetic model was the most informative among the four models of flotation kinetics, and its fitting results can truly reflect the flotation results of barite before and after the microwave action. Through the analysis of barite flotation adsorption experiment under microwave action and with sodium oleate as a collector, this study revealed the mechanism of C1818H33NaO2 on barite flotation under a microwave roaster. This study provides an important reference for the research on efficient barite flotation.