Run Hao

In this research, long-term monitoring data from 2020 to 2023 were used to characterize O₃ pollution in a typical inland city in northwest China (34°21′ N 109°30′ E), which indicated that ozone pollution yielded typical regular fluctuations and high ozone concentrations from April to September were observed. Ozone varied in the range of 16–176 μg/m³, and maximum peaks were found usually at 14:00–17:00 in June and July. Correlation analysis showed a significant positive relationship between ozone and temperature, with correlation coefficients of 0.93. The wind speed exhibits a similar variation as ozone. Meanwhile, negative correlations were not so notably observed among ozone, humidity, VOCs, and NOx. Finally, the empirical kinetic model OZIPR (Ozone Isopleth Plotting Program for Research) was employed to analyze the sensitivity relationship among ozone and precursor compounds by calculating EMKA (Empirical Kinetics Modeling Approach) curves. The EKMA analysis results showed that during the whole ozone pollution period, ozone formation is mainly dominated by VOCs due to all the ratios of VOCs/NOx which fell in the VOCs control region. Therefore, VOCs should be priority controlled and more measures should be taken for better ozone pollution control abatement.

The petrochemical industry is regarded as the main source of anthropogenic VOCs emissions in China. As one of the main sources of unorganized emissions, circulating water is scarcely studied and reported. In this research, six circulating water systems (LC2X, HGLY, YJ, XJ, LC4X and LC5X) of a typical petrochemical enterprise were selected as targets to characterize VOCs emitted from such unorganized emissions. The results showed that there was a great difference in the VOCs disorganized emissions from the six circulating water systems, among which the main VOCs of HG2X, HGLY and YJ were oxygen-containing VOCs (OVOCs), accounting for about 48.0–81.2%. The main compounds of XJ, LC4X and LC5X were alkynes (89.1%), aromatic hydrocarbons (69.7%) and alkane (50.1%), respectively. TVOCs ranged from 276.0 to 23,009.6 µg·m⁻³. Based on POC test results, VOCs emissions of the circulating water system were 1237.5 tons, indicating further control was needed. As for their ambient impact, XJ had higher OFP contribution, and the OFP values of the six systems ranged from 823.3 to 145,739.0 µg·m⁻³, among which the major contributors were aromatic hydrocarbons (0.2–85.1%), OVOCs (0.1–77.2%) and alkynes (1.7–97.6%). In addition, aromatic hydrocarbons showed the largest contribution of the potential of SOA generation, which was more than 88.0%. As far as control was concerned, the replacement of an open cooling tower to closed cooling tower combined with regular POC detection will be an efficient way to control VOCs from such sources.

The VOC emission characteristics of the typical fiber-reinforced plastics (FRPs) industry were studied for an assessment of the impact on the environment. The results showed that the VOC emissions of the typical FRP industry mainly come from grille, sheet, winding, molding, and pultrusion process links, including ketones, aldehydes, alcohols, and benzene series. The benzene series’ concentration represented by styrene was much higher than that of other species. The generation potential of ozone and the SOA in the typical production process were evaluated: in terms of ozone impact, the OFP values of the winding process were the highest, accounting for 65.9% of the total contribution. For the component contribution, the OFP contribution of the benzene series represented by styrene was far more than that of other VOC species, and the styrene mainly came from the use of unsaturated resin. In terms of the SOA impact, the pultrusion process contributed the most to the generation of SOA, accounting for 63.9% of the total SOA contribution. In terms of the component contribution, the contribution of SOA mainly came from the benzene series, accounting for nearly 95% of the total contribution of VOCs. Therefore, FRP enterprises should give priority to controlling the emission of the benzene series.

With the rapid development of metal packaging, volatile organic compounds (VOCs) emissions from the packaging processes are also increasing gradually. It is necessary to research the characteristics of VOCs emissions from such important industrial source and its impact on the possible ozone formation. In this research, three typical metal packaging plants were selected, VOCs emission characteristics were investigated, and their ozone formation potential were evaluated by using maximum incremental reactivity (MIR) coefficient method. The results showed that the VOCs emission characteristics of the selected targets were obviously different. VOCs emitted from plant A and B were mainly oxygenated hydrocarbons, which accounted for 85.02% and 43.17%, respectively. Olefins (62.75%) were the main species of plant C. 2-butanone (82.67%), methylene chloride (23.00%) and ethylene (36.67%) were the major species of plant A, plant B and plant C, respectively. The OFP (ozone formation potential) value of plant B (120.49 mg/m³) was much higher than those values of plant A (643.05 mg/m³) and plant C (3311.73 mg/m³), in which para-xylene, meta-xylene, acetaldehyde and ethylene were the main contributors. The difference in OFP values indicated that water-based ink and water-based coatings should be recommended for large scale application due to less VOCs emission and low ozone formation contribution.

SO₂ which is usually emitted at high temperature is one of the most important air pollutants. It is of great significance to develop high temperature SO₂ adsorbent with high efficiency and low cost. In this work, a series of hydrotalcite-like compound-derived CaAlO and CaXAlO(X = Ce, Co) were prepared by coprecipitation and calcination method, and were employed as adsorbents for SO₂ adsorption at high temperature (700 °C). The structure and surface properties of these adsorbents were characterized by XRD, Brunauer–Emmett–Teller (BET), Derivative thermogravimetric analysis (DTG) and CO₂-TPD (temperature programmed desorption) measurement. Addition of a minor amount of Ce, Co (5 wt%) could significantly increase the number of weak alkalinity sites. CaO in CaCeAlO showed the best SO₂ adsorption capacity of 1.34 g/g, which is two times higher than that of CaO in CaAlO (0.58 g/g).

Enhanced fluorescence sensing of enrofloxacin (ENR) was realized via imprinted responsive inverse opal polymers (RIOPs) by the slow photon effect. Dropropizine, as a dummy template, was adopted instead of ENR to overcome the background interference. Unlike conventional planar-surface RIOPs, curved-surface RIOPs were prepared with crystal moldings formed on the inner face of glass bottles, which showed symmetrical reflective colors perpendicular to the bottle axis. Four RIOPs were prepared, which were named as M170, M200, M220, and M240. M220 had the largest enhancement effect, with a factor of 1.68 times compared with bare ENR solution. This could be related to its better bandgap definition and a slightly large overlap with the ENR emission spectrum. Due to the imprinting effect and enhancement range of the blue band edge, M220 could selectively detect ENR without signals toward the two analogues flumequine and dropropizine. It was also found that the enhancement was most prominent at pH 5.5 in an acetonitrile-acetate ammonium buffer. After incubation with M220, higher slope for the working curve could be obtained, but with a similar detection limit. Probably, the current measurement setup produced the deviation. This study provides the verification for fluorescence enhancement of the ENR target by adsorption on the dummy template-imprinted RIOPs.