Sodium chlorate

About: Sodium chlorate is a research topic. Over the lifetime, 791 publications have been published within this topic receiving 6844 citations.

Chiral Symmetry Breaking in Sodium Chlorate Crystallization

Abstract: Sodium chlorate (NaClO3) crystals are optically active although the molecules of the compound are not chiral. When crystallized from an aqueous solution while the solution is not stirred, statistically equal numbers of levo (L) and dextro (D) NaClO3 crystals were found. When the solution was stirred, however, almost all of the NaClO3 crystals (99.7 percent) in a particular sample had the same chirality, either levo or dextro. This result represents an experimental demonstration of chiral symmetry breaking or total spontaneous resolution on a macroscopic level brought about by autocatalysis and competition between L- and D-crystals.

Selectivity between Oxygen and Chlorine Evolution in the Chlor-Alkali and Chlorate Processes

Abstract: Chlorine gas and sodium chlorate are two base chemicals produced through electrolysis of sodium chloride brine which find uses in many areas of industrial chemistry. Although the industrial production of these chemicals started over 100 years ago, there are still factors that limit the energy efficiencies of the processes. This review focuses on the unwanted production of oxygen gas, which decreases the charge yield by up to 5%. Understanding the factors that control the rate of oxygen production requires understanding of both chemical reactions occurring in the electrolyte, as well as surface reactions occurring on the anodes. The dominant anode material used in chlorate and chlor-alkali production is the dimensionally stable anode (DSA), Ti coated by a mixed oxide of RuO2 and TiO2. Although the selectivity for chlorine evolution on DSA is high, the fundamental reasons for this high selectivity are just now becoming elucidated. This review summarizes the research, since the early 1900s until today, conce...

Contributions of autotrophic and heterotrophic nitrifiers to soil NO and N2O emissions

Abstract: Soil emission of gaseous N oxides during nitrification of ammonium represents loss of an available plant nutrient and has an important impact on the chemistry of the atmosphere. We used selective inhibitors and a glucose amendment in a factorial design to determine the relative contributions of autotrophic ammonium oxidizers, autotrophic nitrite oxidizers, and heterotrophic nitrifiers to nitric oxide (NO) and nitrous oxide (N2O) emissions from aerobically incubated soil following the addition of 160 mg of N as ammonium sulfate kg−1. Without added C, peak NO emissions of 4 μg of N kg−1 h−1 were increased to 15 μg of N kg−1 h−1 by the addition of sodium chlorate, a nitrite oxidation inhibitor, but were reduced to 0.01 μg of N kg−1 h−1 in the presence of nitrapyrin [2-chloro-6-(trichloromethyl)-pyridine], an inhibitor of autotrophic ammonium oxidation. Carbon-amended soils had somewhat higher NO emission rates from these three treatments (6, 18, and 0.1 μg of N kg−1 h−1 after treatment with glucose, sodium chlorate, or nitrapyrin, respectively) until the glucose was exhausted but lower rates during the remainder of the incubation. Nitrous oxide emission levels exhibited trends similar to those observed for NO but were about 20 times lower. Periodic soil chemical analyses showed no increase in the nitrate concentration of soil treated with sodium chlorate until after the period of peak NO and N2O emissions; the nitrate concentration of soil treated with nitrapyrin remained unchanged throughout the incubation. These results suggest that chemoautotrophic ammonium-oxidizing bacteria are the predominant source of NO and N2O produced during nitrification in soil.

Sodium chlorate supplementation reduces E. coli O157:H7 populations in cattle

Abstract: Cattle are a natural reservoir of the food-borne pathogen Escherichia coli 0157:H7 Therefore, strategies that reduce E coli 0157:H7 prior to slaughter will reduce human exposures to this virulent pathogen When bacteria that can anaerobically respire on nitrate (eg, E coli) are exposed to chlorate, they die because the intracellular enzyme nitrate reductase converts nitrate to nitrite, but also co-metabolically reduces chlorate to cytotoxic chlorite Because chlorate is bactericidal only against nitrate reductase-positive bacteria, it has been suggested that chlorate supplementation be used as a strategy to reduce E coli 0157:H7 populations in cattle prior to harvest Cattle (n = 8) were fed a feedlot-style high-grain diet experimentally infected with three strains of E coli O157:H7 Cattle were given access to drinking water supplemented with 25 mM KNO 3 and 100 mM NaCl (controls; n = 4) or 25 mM KNO 3 and 100 mM NaClO 3 (chlorate-treated; n = 4) Sodium chlorate treatment for 24 h reduced the population of all E coli 0157:H7 strains approximately two logs (10 4 to 10 2 ) in the rumen and three logs (10 6 to 10 3 ) in the feces Chlorate treatment reduced total coliforms and generic E coli from 10 6 to 10 4 in the rumen and by two logs throughout the rest of the gastrointestinal tract (ileum, cecum, colon, and rectum) Chlorate treatment reduced E coli O157:H7 counts throughout the intestinal tract but did not alter total culturable anaerobic bacterial counts or the ruminal fermentation pattern Therefore, it appears that chlorate supplementation is a viable potential strategy to reduce E coli O157:H7 populations in cattle prior to harvest