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Reagents for Water Treatment
Published in Willy J. Masschelein, Unit Processes in Drinking Water Treatment, 2020
Cloth and leather are readily oxidized by sodium chlorate. Avoid contact with flames or open fires. Do not smoke while working with chlorate. Contaminated areas should be rinsed immediately with water. Firefighting equipment with water must be installed. Chlorate is of low toxicity (see Chapter 2) but ingestion of 10 to 15 g can cause nausea. Vomiting must be promoted in such cases, and medical assistance is required. Contact with acids must be avoided since chlorine dioxide can develop in such cases. In case of a cloth fire, an extinguishing shower is required; blankets are not efficient. Thermal decomposition of chlorate releases oxygen at 300 °C.
Components of Energetic Compositions
Published in John A. Conkling, Christopher J. Mocella, Chemistry of Pyrotechnics, 2019
John A. Conkling, Christopher J. Mocella
Potassium chlorate was used in the first successful colored-flame compositions in the mid-1800s and it remains in use today in colored-smoke compositions, firecrackers, toy pistol caps, matches, and some color-producing fireworks.
Disinfection
Published in Syed R. Qasim, Wastewater Treatment Plants, 2017
Chlorine dioxide is a more powerful disinfectant than chlorine, although it has a lower oxidation potential (Table 14-2). When produced in the absence of excess free chlorine, it (I) does not react with ammonia, therefore lasting longer than free chlorine residual, and (2) does not produce THMs and other chlorinated organic by-products of concern. If excess chlorine is present, many undesired effects are associated. Among these are (a) production of chlorinated organic by-products, (b) production of hypobromous acid and brominated compounds, and (c) production of chlorite and chlorate ions by disproportion with pH below 2 and above 11. Both chlorite and chlorate ions have undesired environmental effects. Free chlorine dioxide residuals have a short life and are less harmful to aquatic life than chlorine. Residuals may be destroyed by a sulfur dioxide reaction [Eq. (14-20)]: () 5SO2 + 6H2O + 2ClO2→5H2SO4 + 2HCl
Adaptive neuro-fuzzy approach to sodium chlorate cell modeling to predict cell pH for energy-efficient chlorate production
Published in Chemical Engineering Communications, 2021
Sreepriya Sreekumar, Aparna Kallingal, Vinila Mundakkal Lakshmanan
Sodium chlorate production is one of the biggest energy-intensive industrial-scale electrochemical processes. The global production rate of sodium chlorate is 3.6 million tons annually. The paper industry consumes a major part of the sodium chlorate produced; it is used to manufacture chlorine dioxide that serves as a bleaching agent. It is also used to produce ammonium perchlorate, which is used as an oxidizer in rockets. Chlorates are also used for agricultural applications as defoliant and herbicide, also as chemical oxygen generators in aircraft and submarines, and as an oxidizer for uranium milling (Vogt 1981; Viswanathan 1984; Hedenstedt 2017). A major issue in sodium chlorate production is high-power consumption. Approximately 5000–6000 kWh energy is required to produce a ton of sodium chlorate crystal (Karlsson and Cornell 2016). It was estimated that the power consumption accounts for over 70% of the production costs. Hence, the effectiveness of the process must be improved, which will be beneficial from the economic and environmental points of view.
Stability of emulsion liquid membrane using blended nonionic surfactant and multi-walled carbon nanotubes (MWCNTs) for methylparaben removal
Published in Journal of Dispersion Science and Technology, 2023
Rahulkumar Shirasangi, Himanshu P. Kohli, Mousumi Chakraborty
Parabens (p-hydroxybenzoic acid esters) are used in drugs, cosmetics, or food items as preservatives and have become common pollutants in ecological media.[1] Human exposure to parabens is an increasing public health concern since parabens have been described to be endocrine-disrupting compounds (EDCs) that act in the body like estrogen. Xue et al.[2] observed that the trophic magnification factor of methylparaben is 1.83, signifying substantial biomagnification and bioaccumulation of this compound in the marine food web. Extensive usage of parabens in detergents, cosmetics, and dyes leads to abundant existence in the soil and wastewater. Chin et al.[3] stated that methods like ozonation, chlorine dioxide treatment, photosensitized degradation, and so on, effectively remove parabens but produce disinfection by-products. For example, chlorite (ClO2−) and chlorate (Cl2O2) are disinfection by-products released during chlorine dioxide treatment, which are potentially toxic.[4] Emulsion liquid membrane (ELM) is a favorable separation method for organic and inorganic wastewater treatment. ELM is a simple process with several merits, like high contact area, high selectivity and efficiency, simultaneous extraction and stripping process, less chemical and energy consumption, and low operating cost.[5] Emulsion instability is the primary concern for large-scale industrial separations, as membrane breakage reduces extraction efficiency.[5] The addition of blended surfactant and nanoparticle enhances the emulsion stability. Li et al.[6] stated that blended surfactants could improve the flexibility of the surfactant layer formed and the partitioning of surfactants into the oil–water interface. The nanoparticle layers around the droplets have rigid adsorption at oil–water interface and offer steric interference to coalescence, thereby stabilizing the droplets.[7]