Chlorine Gas Research Articles

Evaluation and Management of Health and Safety Risks of Chlorine Gas in Transportation Routes

Background: More than 90% of goods movement in Iran is done by road transport. A significant part of these materials is dangerous goods. Considering that chlorine gas is considered a toxic and oxidizing substance, predicting the way of release and mortality due to accidental leakage of chlorine gas can be a crucial tool in adopting preventive strategies. This study aims to evaluate the safety of chlorine gas transportation and analyze the consequences of its release. Materials and Methods: This cross-sectional-analytical study was conducted in 2020 in Tehran. The transportation risk rating index was used to measure and evaluate the quantitative risk of transportation of hazardous materials. PHAST software was used to determine the consequence of possible accident scenarios on the transportation route. In the final stage, according to the amount of traffic, the time and manner of response to emergencies by the fire and emergency organization were simulated using Pathfinder software. Results: In this evaluation, the chlorine risk rating was calculated as 192. The worst possible scenario was a catastrophic rupture of chlorine in the second half of 2021. As a result of the accident, up to a radius of 1800 m from the center of the leak, the dangerous concentration is equal to 20 ppm, that is, equal to the ERPG3 limit. The simulation results showed that the release of poisonous chlorine gas leads to the death of 10% of people up to a radius of 192 m around the scenario. Conclusion: In the scenario of the sudden release of chlorine, in which people need to escape and move away from the accident site, it was found that it takes more than 24 minutes to leave the ERPG-3 area. Considering that the assumed average speed of 1.15 m/s is the average speed of people and naturally the speed of sensitive people is much lower in the conditions of an accident, it can be concluded that in the scenario of a sudden leak, a significant part of the people involved in the accident may suffer severe and irreparable damage.

Lipid Oxidation and Volatile Compounds of Almonds as Affected by Gaseous Chlorine Dioxide Treatment to Reduce Salmonella Populations.

The effects of gaseous chlorine dioxide (ClO2) treatment, applied to inactivate Salmonella, on lipid oxidation, volatile compounds, and chlorate levels of dehulled almonds were evaluated during a 3 month accelerated storage at 39 °C. At treatment levels that yielded a 2.91 log reduction of Salmonella, ClO2 promoted lipid oxidation as indicated by increased peroxide values, total acid number, conjugated dienes, and thiobarbituric acid-reactive substances. Furthermore, several chlorine-containing volatile compounds including trichloromethane, 1-chloro-2-propanol, 1,1,1-trichloro-2-propanol, and 1,3-dichloro-2-propanol were identified in ClO2-treated samples. However, all the volatile chlorine-containing compounds decreased during the 3 months of storage. Chlorate (26.4 ± 5.1 μg/g) was found on the ClO2-treated samples. The amounts of non-ethanol alcohols, aldehydes, and carboxylic acids increased following ClO2 treatments. Some volatiles such as 2,3-butanediol that were present in non-treated samples became non-detectable during post-ClO2 treatment storage. Overall, our results demonstrated that gaseous ClO2 treatment promoted lipid oxidation, generation of volatiles of lipid origin, and several chlorine-containing compounds.

Reactive airway dysfunction syndrome caused by chlorine gas from the point of view of Persian Medicine: A review article

Introduction: Chlorine gas inhalation is a toxic respiratory irritant associated with high lung complications. Despite its wide industrial and domestic applications such as bleaching detergents, there is no specific treatment for chlorine gas poisoning yet and common standard treatments are mostly supportive. In this regard, this study aimed to find a new treatment for this pathogenesis from the perspective of Persian medicine (PM).
 Materials and methods: In this review study, at first, we searched the etiologies and clinical symptoms associated with chlorine gas poisoning in modern medicine and then compared them with similar etiologies and symptoms in valuable Persian medical manuscripts. Then we reviewed the proposed treatments for similar illnesses from the point of view of PM.
 Results: The pathology of lung damage caused by inhalation of chlorine gas is reactive airway dysfunction syndrome (RADS), which leads to dyspnea, hypoxemia, respiratory tract obstruction, pneumonia, pulmonary edema, and finally acute respiratory distress syndrome (ARDS). In a comparative study, it seems that this pathology has the closest similarity with the Persian term“Varme-e-harr riye”. The treatment strategy for this syndrome in PM is bloodletting at the first and then the application of cold-temperament foods and medications to improve the lungs.
 Conclusion: According to the compatibility of acute pulmonary edema caused by chlorine inhalation and “varam-e-harr riye” in PM, it seems that wet cupping can be considered as a suggested primary and emergency treatment for this pathology in future clinical studies.

Chlorine gas hazardous material incident in Karachi, Pakistan: A clinical experience from an emergency department of a tertiary care hospital.

To determine the clinical characteristics, management and outcomes of patients presenting with chlorine gas exposure in an emergency setting. The single-centre, retrospective cross-sectional study was conducted at the emergency department of Aga Khan University Hospital, Karachi, and comprised data of all patients who presented on March 06, 2020, due to acute chlorine gas exposure after a specific industrial accident. Demographic and clinical data was recorded from the medical record files. The association between risk factors and complications was explored. Data was analysed using SPSS 20. There were 51 male patients with a mean age of 33.10±8.37 years. The most commonly affected organ system was respiratory 49(96%), with 43(84.3) having shortness of breath. Eye irritation was found in 44(86.3%) cases and the central nervous system was involved in 14(27.4%). Most of the patients were admitted from the emergency department 36(70%). Regarding treatment, 1(1.9%) patient each required invasive and non-invasive mechanical ventilation. Complications included toxic pneumonitis 3(5.9%) and pneumomediastinum 1(1.7%). No correlation was found between smoking and complications (p>0.05). Most patients showed complete resolution of symptoms after receiving supportive treatment, while complications were rare and there was no mortality.

Quantification of Chlorine Gas Generation in Mixed-Acid Vanadium Redox Flow Batteries

Quantification of Chlorine Gas Generation in Mixed-Acid Vanadium Redox Flow Batteries

Diffusion simulation and risk assessment model establishment of chlorine gas leakage based on terrain conditions

This study researches the impact of terrain factors on chlorine gas diffusion processes based on SLAB model. Simulating the law of wind speed changing with altitude by calculating the real-time speed with vertical height combing actual terrain data, and integrating the influence of terrain on wind speed by using Reynolds Average Navier-Stokes (RANS) algorithm, K-turbulence model, and standard wall functions, then plotting the gas diffusion range in the map with terrain data according to the Gaussian-Cruger projection algorithm and dividing the hazardous areas according to the public exposure guidelines (PEG). The accidental chlorine gas releases near Lishan Mountain, Xi'an City, were simulated by the improved SLAB model. The results show that there are obvious differences analyzing contrastively the endpoint distance and area of chlorine gas dispersion under real terrain condition and ideal condition at different times; it can be found that the endpoint distance of the real terrain conditions is 1.34km shorter than that of the ideal conditions at 300s with terrain factors, and also the thermal area is 3,768,026m2 less than that of the ideal conditions. In addition, it can predict the specific number of casualties within different levels of harm at 2min after chlorine gas dispersion, and casualties are constantly changing over time. The fusion of terrain factors can be used to optimize the SLAB model, which is expected to provide an important reference for effective rescue.

Assessment of safety control measures for centralized Chlorine gas system

As a glove manufacturing plant, the chemical is one of the most highly used materials. Some chemicals impact human health, environmental aspects, and physical hazards such as highly flammable gas. Chlorine gas is one of them. Besides the accidental release of chlorine gas incidents, ill-health issues are another aspect that should be taken care of. This study aims to determine the current chlorine concentration at a centralized chlorine gas manifold system in a rubber glove manufacturing plant and evaluate the existing safety control measures. A concept of safety by design, inherently safety, and the fail-safe system was considered during the study. The results show that the chlorine concentration level during drum replacement by the crew is at an average of 1.154 ppm and the standard deviation at 0.3478. The highest concentration was at 1.8 ppm. The wet scrubber assessment was done using the Industrial Ventilation and visual assessments and measurements within the system, including capture velocity, face velocity, and duct velocity or transport velocity. Other assessed parameters are total pressure, static pressure, and velocity pressure. The assessment found that the duct performance for all parameters complies with a minimum requirement of the American Conference of Governmental Industrial Hygienists (ACGIH) guidelines.

Separation of a Gas Mixture Containing Uranium Hexafluoride, Hydrogen Fluoride, and Chlorine Trifluoride

Separation of a Gas Mixture Containing Uranium Hexafluoride, Hydrogen Fluoride, and Chlorine Trifluoride

Небезпечні хлорити у питній воді: утворення та видалення з використанням діоксиду хлору У технології водопідготовки

he aim of work was to study the features of the formation and removal of toxic chlorites at the treatment facilities of the Dnieper water pipeline in Kyiv, where chlorine dioxide is used in water treatment technology, and the influence of priority natural and technological factors on these processes. Materials and methods: The studies were carried out in 2021-2022. at the Dnieper waterworks in Kyiv, where chlorine dioxide is used instead of chlorine in water treatment technology. We have analyzed data from water studies for the content of dioxide and chlorites, carried out at treatment facilities by the laboratory of the Dnieper water pipeline in order to establish the features of the formation and efficiency of chlorite removal in water treatment technology. Also, selective studies of chlorine dioxide and chlorites in the water supply were carried out by titrimetric and photometric methods, the results of which coincide with the data obtained on the water supply using the ion chromatography method. Main results: A positive hygienic assessment of the modern new technology for the preparation of drinking water from surface sources using chlorine dioxide instead of chlorine gas is given. It is shown that with high purifying and disinfecting effects of water treatment with chlorine dioxide, its by-products, in particular, toxic chlorites, are constantly formed in it, the levels of which are directly dependent on the doses of chlorine dioxide used, which vary according to the seasons of the year. In general, the primary dose of chlorine dioxide and chlorites in the water after the clean water tank (CWT) entering the water supply networks is reduced by 89,3-92,0% for chlorine dioxide, and by 76,2-85,6% for chlorites. At the same time, the concentration of chlorine dioxide in disinfected drinking water is always within the normal range - not less than 0,1 mg/dm3, and chlorites - most often exceeds the national hygienic standard (0,2 mg/dm3), but does not exceed the standard recommended by the WHO ( 0,7 mg/dm3). The highest concentrations of chlorites are formed in water in summer (on average 0,35 mg/dm3) in accordance with the increased doses of chlorine dioxide during this period (on average 2,51 mg/dm3), and the lowest in winter (on average 0,17 mg/dm3). Conclusions: The studies carried out at the Dnieper water pipeline, where chlorine dioxide was introduced into the traditional water treatment technology, made it possible to establish the following. The process of treating natural water with chlorine dioxide is accompanied by the formation of its by-products in water, mainly toxic chlorites, the levels of which depend on the doses of chlorine dioxide used and are the lowest in winter and summer. After coagulation treatment of the source water with aluminum sulfate and ferric chloride (ratio 10:4-5), settling and filtration, the levels of chlorites in drinking water (CWT) decrease intensively, but do not always reach regulatory values. In the summer period, the maximum levels of chlorites in drinking water with RCHV can be higher than the national hygienic standard (0,2 mg/dm3) and range up to 0,7 mg/dm3, which corresponds to the WHO recommended standard for this substance in drinking water. The issue of revising the national standard for chlorites in water from 0,2 mg/dm3 to 0,7 mg/dm3 after appropriate scientific justification is being raised.

Ophthalmic Manifestations of Chlorine Gas Exposure: What Do We Know So Far?

Chlorine gas is a hazardous substance that can cause severe health effects when inhaled or exposed to the skin. It is an odorless, colorless gas in many industrial and manufacturing settings and conflict areas. While exposure to chlorine gas is generally limited to the workplace and public areas, there are instances in which people may be exposed to high levels of chlorine gas for a short period of time due to spills, mishaps on the road or railroads, or other tragedies. In addition to the general health effects of chlorine gas, this essay will focus on the effects of chlorine gas on the eyes. The eyes are particularly sensitive to chlorine gas, and exposure can cause various symptoms, ranging from mild irritation to severe damage. Symptoms of chlorine gas exposure to the eyes include redness, burning, tearing, and blurred vision. In more serious cases, exposure to chlorine gas can cause permanent damage to the eyes, including corneal ulcers, scarring, and blindness. It is important to be aware of the signs and symptoms of chlorine gas exposure and the potential long-term effects to take the necessary steps to protect oneself. In addition to the potential health effects, it is important to understand the properties of chlorine gas. Chlorine gas is heavier than air and tends to settle in low-lying areas. It is highly reactive and can react with other substances to form hazardous compounds. As such, it is important to be aware of the potential for chlorine gas to react with other environmental substances and accumulate in certain areas. Finally, it is important to understand the background of chlorine gas use in various conflict areas. Chlorine gas has been used as a chemical weapon for centuries, and its use in modern warfare has been documented in various conflicts. As such, it is important to be aware of the potential for chlorine gas to be used in war zones and to take the necessary precautions to protect oneself. In conclusion, chlorine gas is a hazardous substance that can cause severe health effects when inhaled or exposed to the skin. The eyes are particularly sensitive to chlorine gas, and exposure can cause various symptoms, ranging from mild irritation to severe damage. It is important to be aware of the signs and symptoms of chlorine gas exposure and the potential long-term effects to take the necessary steps to protect oneself. Additionally, it is important to understand chlorine gas's properties and its background use in various conflict areas.

First Principles Study of Toxic Gas Molecules Adsorption on Group IVA (C, Si, Ge) 2-Dimensional Materials

Two-dimensional materials from group IVA namely graphene, silicene, and germanene have gained research interest in various fields of applications recently due to their extraordinary properties. These substrates have been successfully synthesized and are found to have interesting gas sensing capabilities. In this work, first-principles study using density functional theory is carried out to investigate the adsorption of toxic gases such as CO, Cl2, NO2, and COCl2 on these monolayers. We analyze the best adsorption site and orientation for these molecules on the monolayers by calculating the adsorption energy. Charge transfer, the density of state (DOS) and band diagram calculations are performed to explore the changes in their electronic and structural properties due to the adsorbed gas molecules. As for the sensing performance, crude estimations of the sensitivity and recovery time are performed. The results show that silicene and germanene monolayers are better at detecting CO and NO2 as compared to graphene. They have a short recovery time for CO but a long recovery time for NO2 implying that they are better for scavenging NO2. Besides, silicene is also a better gas sensor for chlorine gas with a 44 min recovery time. As for graphene, it is the best gas sensor for phosgene among the substrates. This study gives a clear prediction of substrates for the detection of these toxic gases.

The Rise of Trichlorides Enabling an Improved Chlorine Technology.

Chlorine plays a central role for the industrial production of numerous materials with global relevance. More recently, polychlorides have been evolved from an area of academic interest to a research topic with enormous industrial potential. In this minireview, the value of trichlorides for chlorine storage and chlorination reactions are outlined. Particularly, the inexpensive ionic liquid [NEt3 Me][Cl3 ] shows a similar and sometimes even advantageous reactivity compared to chlorine gas, while offering a superior safety profile. Used as a chlorine storage, [NEt3 Me][Cl3 ] could help to overcome the current limitations of storing and transporting chlorine in larger quantities. Thus, trichlorides could become a key technique for the flexibilization of the chlorine production enabling an exploitation of renewable, yet fluctuating, electrical energy. As the loaded storage, [NEt3 Me][Cl3 ], is a proven chlorination reagent, it could directly be employed for downstream processes, paving the path to a more practical and safer chlorine industry.

Syria used chlorine gas in Douma, chemical weapons agency says

The Organisation for the Prohibition of Chemical Weapons (OPCW) has again concluded that the Syrian Air Force used chemical weapons, breaking international law. The OPCW published the findings Jan. 27 in the third report of its Investigation and Identification Team (IIT). The IIT investigates the use of chemical weapons in the Syrian Arab Republic and establishes responsibility. In its latest report, the team used multiple pieces of evidence, including chemical analyses, to conclude that at least one air force helicopter dropped yellow cylinders containing chlorine gas on two apartment buildings, killing 43. “The world now knows the facts—it is up to the international community to take action, at the OPCW and beyond,” OPCW director general Fernando Arias says in a statement .

Computational molecular design to assist modification of single – walled carbon nanotubes with B, N, Al, Si, P, and S dopant atoms for Cl2 gas sensor application

Chlorine (Cl2) gas is toxic to humans. Exposure to this gas can cause skin and eye irritation, suffocation, and even death if a person is continuously exposed to Cl2 gas at high concentrations. Therefore, it is necessary to develop a detection sensor to minimize its impact. In this study, pristine Single-Walled Carbon Nanotubes (SWCNT) and SWCNT doped with Boron (B), Nitrogen (N), Aluminum (Al), Silicon (Si), Phosphorus (P), and Sulfur (S) dopant atoms were tested as sensors for Cl2 gas detection. The results show that the reaction between SWCNT and Cl2 gas is exothermic and occurs spontaneously. The bond distance formed between the Cl and B atoms in B-doped SWCNT is the shortest compared to other systems. The addition of B dopant atoms can also improve the electronic properties of the SWCNT. Furthermore, the addition of Al and Si atoms as dopants to the SWCNT also resulted in a high adsorption activity. From these results, it was concluded that B, Al, and Si dopants were the most effective dopants used to enhance the sensitivity of SWCNT to chlorine gas.

Syrian Air Force used chlorine gas in 2018 Douma attack, chemical weapons agency says

Syrian Air Force used chlorine gas in 2018 Douma attack, chemical weapons agency says

Maturation of pathogenic biofilms induces enhanced resistance against gaseous chlorine dioxide.

Biofilms are surface-associated microbial clusters embedded in extracellular polymeric substances. Biofilms formed on food-contact surfaces create challenges for the food industry due to their increased tolerance to antimicrobial agents and disinfectants. This study aimed to evaluate the effect of the biofilm maturation period on their resistance to gaseous ClO2. Listeria monocytogenes, Salmonellaserotype Typhimurium, and Escherichia coli O157:H7 biofilms formed on stainless steel (SS) and high-density polyethylene (HDPE) surfaces were investigated. The total cell mass and protein content significantly increased (P<.05) between the second and the fifth day of maturation, and the biofilms' resistance to gaseous ClO2 increased as they matured. Generally, the cell counts of 0-day-old L. monocytogenes, Salm. Typhimurium, and E. coli O157:H7 biofilms on SS and HDPE reduced below the detection limit (0.48 log CFU/cm2) within 5min. The cell counts of 2-day-old biofilms of the three pathogens were reduced by 6.22 to over 7.52 log, while those of 5-day-old biofilms were reduced by 3.64 to over 6.34 log after 20min of treatment with 30 ppmv of gaseous ClO2. Therefore, as resistance increases with biofilm maturation, daily gaseous ClO2 treatment would maximize the antimicrobial efficacy of the cleaning strategy against biofilms.

Visible Blue LED Mediated Aqueous Photochlorination of PVC to CPVC: A Shrinking Core Kinetic Model and Experimental Study

The visible blue LED mediated aqueous suspension photochlorination of polyvinyl chloride (PVC) to chlorinated polyvinyl chloride (CPVC) is described. A shrinking core model (SCM) of the photochlorination process is proposed by considering diffusional resistances of chlorine gas at various steps involved in the photochlorination of PVC particles. Diffusion of Cl2 through the outer product layer contributes major resistance to the overall reaction, and this is the rate-controlling step. The proposed SCM model estimated values are in close agreement with the experimental data.

Efficiency of nutrients recovery from sugarcane vinasse treatment by different electrodialysis configurations and in sequential-batch operation

Electrodialysis (ED) is reported as a promising technique for vinasse desalination and nutrients recovery for mineral (K-struvite) and organomineral fertilizers production. The use of ultrafiltered vinasse as an electrolyte solution, as well as fouling layer formation on membrane surface, were evaluated by operating the ED for a longer operation time. After 40 h of test time, it was observed that the ED performance was stable, with high efficiencies of removal (>77 %) and recovery (>70 %) of potassium. Ultrafiltered vinasse did not affect the efficiencies of nutrient removal and recovery, and provides as benefits a reduction in the costs of water and chemical demand, and the production of organo-mineral fertilizer. Membrane fouling was considerably reduced after the cleaning procedure. Also, ED operation was evaluated in three configurations, namely A, B, and C, with 5, 3, and 2 compartments, respectively. The lower number of compartments did not affect the ED performance, with similar performance as that observed for the Configuration A. Removal and recovery efficiencies for potassium, calcium and magnesium were similar in all experiments, being 80 and 72 %, 57 % and 49 %, 46 % and 8 %, respectively. For the specific energy consumption per mole of K+ (E/K+), no significant differences were found between the three configurations for both electrolyte solutions, being around 0.3049 ± 0.012 KWh/Kg K+. Of the configurations evaluated, Configuration C demonstrated to be a viable alternative for implementation in a biorefinery for sugarcane vinasse treatment. Besides the high performance presented, this configuration has advantages such as: reduction in energy use, membrane area, area required for system installation, water and chemical demand, and the potential recovery of gaseous chlorine, which can be used as a decolorizing agent.

Lung injury and oxidative stress induced by inhaled chlorine in mice is associated with proinflammatory activation of macrophages and altered bioenergetics

Chlorine (Cl2) gas is a highly toxic and oxidizing irritant that causes life-threatening lung injuries. Herein, we investigated the impact of Cl2-induced injury and oxidative stress on lung macrophage phenotype and function. Spontaneously breathing male C57BL/6J mice were exposed to air or Cl2 (300 ppm, 25 min) in a whole-body exposure chamber. Bronchoalveolar lavage (BAL) fluid and cells, and lung tissue were collected 24 h later and analyzed for markers of injury, oxidative stress and macrophage activation. Exposure of mice to Cl2 resulted in increases in numbers of BAL cells and levels of IgM, total protein, and fibrinogen, indicating alveolar epithelial barrier dysfunction and inflammation. BAL levels of inflammatory proteins including surfactant protein (SP)-D, soluble receptor for glycation end product (sRAGE) and matrix metalloproteinase (MMP)-9 were also increased. Cl2 inhalation resulted in upregulation of phospho-histone H2A.X, a marker of double-strand DNA breaks in the bronchiolar epithelium and alveolar cells; oxidative stress proteins, heme oxygenase (HO)-1 and catalase were also upregulated. Flow cytometric analysis of BAL cells revealed increases in proinflammatory macrophages following Cl2 exposure, whereas numbers of resident and antiinflammatory macrophages were not altered. This was associated with increases in numbers of macrophages expressing cyclooxygenase (COX)-2 and inducible nitric oxide synthase (iNOS), markers of proinflammatory activation, with no effect on mannose receptor (MR) or Ym-1 expression, markers of antiinflammatory activation. Metabolic analysis of lung cells showed increases in glycolytic activity following Cl2 exposure in line with proinflammatory macrophage activation. Mechanistic understanding of Cl2-induced injury will be useful in the identification of efficacious countermeasures for mitigating morbidity and mortality of this highly toxic gas.

Development and validation of a new in situ technique to measure total gaseous chlorine in air

Abstract. Total gaseous chlorine (TClg) measurements can improve our understanding of unknown sources of Cl in the atmosphere. Existing techniques for measuring TClg have been limited to offline analysis of extracted filters and do not provide suitable temporal information on fast atmospheric processes. We describe high-time-resolution in situ measurements of TClg by thermolyzing air over a heated platinum (Pt) substrate coupled to a cavity ring-down spectrometer (CRDS). The method relies on the complete decomposition of TClg to release Cl atoms that react to form HCl, for which detection by CRDS has previously been shown to be fast and reliable. The method was validated using custom organochlorine permeation devices (PDs) that generated gas-phase dichloromethane (DCM), 1-chlorobutane (CB), and 1,3-dichloropropene (DCP). The optimal conversion temperature and residence time through the high-temperature furnace was 825 ∘C and 1.5 s, respectively. Complete conversion was observed for six organochlorine compounds, including alkyl, allyl, and aryl C–Cl bonds, which are amongst the strongest Cl-containing bonds. The quantitative conversion of these strong C–Cl bonds suggests complete conversion of similar or weaker bonds that characterize all other TClg. We applied this technique to both outdoor and indoor environments and found reasonable agreements in ambient background mixing ratios with the sum of expected HCl from known long-lived Cl species. We measured the converted TClg in an indoor environment during cleaning activities and observed varying levels of TClg comparable to previous studies. The method validated here is capable of measuring in situ TClg and has a broad range of potential applications.