Chlorine poisoning caused by improper mixing of household disinfectants during the COVID-19 pandemic

Background During the coronavirus disease 2019 (COVID-19) pandemic, many people have abused and misused disinfectants, leading to many poisoning incidents. However, there are few clinical case reports of poisoning caused by mixed household disinfectants. This study summarized the clinical characteristics and treatment effects of chlorine poisoning caused by improper mixing of hypochlorite bleach with acidic cleaning agents to improve the understanding of the disease. Methods We retrospectively analyzed the basic data, clinical symptoms, treatment methods, imaging, and other clinical data of seven patients with chlorine poisoning, caused by an improper mixture of hypochlorite bleach and acidic cleaning agents, who were admitted to the National Army Poisoning Treatment Center. Results The seven patients (three men and four women) had an average age of 48.8 years (18–67 years). The average poisoning time (time from exposure to poison to treatment) was 57 h (4–240 h). All seven patients were involved in cleaning bathrooms during the COVID-19 pandemic. Chest computed tomography scans showed bilateral lung effusions or inflammatory changes in five patients and no obvious exudation or inflammatory changes in two. The partial pressure of oxygen decreased in six patients, and respiratory failure occurred in one. Five patients had different degrees of increase in white blood cell count. For treatment, humidified oxygen therapy, non-invasive mechanical ventilation, intravenous corticosteroids, inhaled hormone, bronchial spasmolytics, antibiotics, and other symptomatic and supportive treatments were provided. The average length of hospital stay was 7 days (4–9 days). All seven patients recovered and were discharged. Conclusions Improper mixing of house disinfectants during the COVID-19 pandemic may cause damage to the respiratory system due to chlorine poisoning. Corticosteroids may improve lung exudation in severe cases. Additionally, symptomatic supportive treatment should be performed early.

Steam Reforming of Chloroform-Ethyl Acetate Mixture to Syngas over Ni-Cu Based Catalysts

NiCuMoLaAl mixed oxide catalysts are prepared and applied in the steam reforming of chloroform-ethyl acetate (CHCl3-EA) mixture to syngas in the present work. The pre-introduction of Cl- ions using chloride salts as modifiers aims to improve the chlorine poisoning resistance. Catalytic tests show that KCl modification is obviously advantageous to increase the catalytic life. The destruction of catalyst structure induced by in situ produced HCl and carbon deposits that occurred on acidic sites are two key points for deactivation of reforming catalysts. The presence of Cl− ions gives rise to the formation of an Ni-Cu alloy, which exhibits a synergetic effect on catalyzing reforming along with metallic Ni crystals formed from excess nickel species, and giving an excellent catalytic stability. Less CHCl3 and more steam can also increase the catalytic stable time of KCl-modified NiCuMoLaAl reforming catalyst.

Y-Modified MCM-22 Supported PdOx Nanocrystal Catalysts for Catalytic Oxidation of Toluene

A series of rare earth elements (REEs)-modified and Mobil Composition of Matter (MCM)-22-supported Pd nanocrystal catalysts were synthesized via a high-temperature solution-phase reduction method and tested for toluene complete oxidation. These catalytic materials were systematically characterized by N2 adsorption/desorption, X-ray powder diffraction (XRD), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), energy-dispersive spectroscopy (EDS), inductively coupled plasma atomic emission spectroscopy (ICP-AES), temperature-programmed surface reaction of toluene (toluene-TPSR) and X-ray photoelectron spectroscopic (XPS) techniques in order to investigate the structure–catalytic property relationship. Moreover, catalysts with an appropriate yttrium content greatly improved the catalytic activity of 0.2%Pd/MCM-22. PdOx (x = 0, 1) nanoparticles, ranging from 3.6 to 6.8 nm, which were well distributed on the surface of MCM-22. Efficient electron transfer from the Pd2+/Pd0 redox cycle facilitated the catalytic oxidation process, and the formation of Pd (or Y) –O–Si bonds improved the high dispersion of the PdOx and Y2O3 particles. Toluene–TPSR experiments suggested that the addition of Y2O3 improved the physical/chemical adsorption of 0.2%Pd/MCM-22, thus increasing the toluene adsorption capacity. Then, 0.2%Pd/7.5%Y/MCM-22 exhibited the highest catalytic performance. In addition, this catalyst maintained 95% conversion with high resistance to water and chlorine poisoning, even after toluene oxidation at 210 °C for 100 h, making it more valuable in practical applications.

Oxidative Degradation of Trichloroethylene over Fe2O3-doped Mayenite: Chlorine Poisoning Mitigation and Improved Catalytic Performance

Mayenite was recently successfully employed as an active catalyst for trichloroethylene (TCE) oxidation. It was effective in promoting the conversion of TCE in less harmful products (CO2 and HCl) with high activity and selectivity. However, there is a potential limitation to the use of mayenite in the industrial degradation of chlorinated compounds—its limited operating lifespan owing to chlorine poisoning of the catalyst. To overcome this problem, in this work, mayenite-based catalysts loaded with iron (Fe/mayenite) were prepared and tested for TCE oxidation in a gaseous phase. The catalysts were characterized using different physico-chemical techniques, including XRD, ICP, N2-sorption (BET), H2-TPR analysis, SEM-EDX, XPS FESEM-EDS, and Raman. Fe/mayenite was found to be more active and stable than the pure material for TCE oxidation, maintaining the same selectivity. This result was interpreted as the synergistic effect of the metal and the oxo-anionic species present in the mayenite framework, thus promoting TCE oxidation, while avoiding catalyst deactivation.

Enhancement of resistance to chlorine poisoning of Sn-modified MnCeLa catalysts for chlorobenzene oxidation at low temperature

The Sn-modified MnCeLa catalysts show significantly higher resistance to chlorine poisoning than MnCeLa catalysts at different temperatures.