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Safety first Potassium chlorate (KClO3) is a strong oxidizer. Do not heat or rub it with combustibles, like carbon, sugar, etc. With Phosphorus or even sulphur in may ignite easily. Avoid contact with acids as well. Molecular formula: KClO3 Formula weight: 122.55 CAS number: 3811-04-9 Melting point: 356oC Safety: R 9,20/22; S 13 16 27 RTECS #: FO0350000 EINECS: 223-289-7



How does it workElectrolyzing an alkali chloride solution results in the following reactions:anode: 2 Cl- -> Cl2 + 2ecathode: 2 H2O + 2e -> 2OH- + H2Now the trick: In commercial plants, chlorine gas and caustic soda NaOH isproduced this way. A diaphragm should be put to prevent intermixing theOH- and Cl2, otherwise the OH- will react withthe chlorine by:2OH- + Cl2 -> 2 ClO- + H2thus generating hypochlorite. The first target for making chlorate however ishypochlorite, to be oxidized to chlorate, so this process must generatehypochlorite and therefore mixing should take place.When the solution heats up by heat loss (because the voltage is usuallyhigher than required to yield the needed electrochemical energy), thehypochlorite will be oxidized to chlorate by:3 ClO- -> ClO3- + 2 Cl-and therefore the chloride ions will react again with the OH-. Sothe total reaction (helped by the electric energy) is:2Cl- + 3 H2O -> 2 ClO3- + 3H2The oxidation state of the chlorine will be from -1 (Cl-) to +5(ClO3-), which requires 6 electrons per Cl- ion.Theoretically one mol electrons is equivalent by the physical constant ofFaraday which is 96560 Coulombs (Ampere-seconds), which is nearly 27Ampere-hours per electron (mole). To oxidize one mole of Cl-to ClO3- costs 6 * 27 = 162 Ah. For one mole KCl (74.5grams) to KClO3 (122.5 grams) one needs 162 Ah in theory. In practiceit is more, estimate about 200 Ah.

  • A good test for the purity is :Flame test. Put an inert titanium or magnesia stick (stainless steel is also OK) in the KClO3 slurry after rinsing. Hold it in a colorless flame and no yellow Na color should appear. Even small traces of Na will color the flame yellow. The color should be lilac like.

  • Dissolve a few crystals in AgNO3 solution. Only a slight precipitation (or none at all) should appear. When there is more precipitation, too much chloride ions are in the solution.

You can recrystallize it by dissolving it in boiling water just enough water to dissolve everything. Then allow it to cool and put it into the fridge or freezer or outdoors in cold winter weather. After cooling pour off the water and dry the crystals. Now they should be more pure. Note: Do not mix it with any combustible stuff while rubbing it in a mortar,as a spontaneous reaction might occur ! The powder is the chlorate ready to use.

Potassium chlorate is a powerful oxidizer salt that, when mixed with a fuel source, has been used as a homemade explosive (HME). As an inorganic salt, potassium chlorate has no appreciable vapor pressure under ambient conditions and requires temperatures exceeding 300 C for decomposition. However, detection of potassium chlorate by trained canines has been demonstrated, implying that it exudes a vapor signature with one or more volatile compounds, although no such species have been confirmed to date. In this work, solid-phase microextraction with a novel on-fiber derivatization reaction was used to interrogate the headspace of several potassium chlorate samples of varying purity, as well as that of related chlorinated salts and explosive mixtures. This analysis showed the presence of few volatile species in the headspace of potassium chlorate other than vaporous chlorine, detected as the derivatized product, chloro-2-propanol. Relative amounts of chloro-2-propanol could be compared between potassium chlorate variants, and could be detected in the presence of other volatile species associated with the fuels.

Flower induction of longan (Dimocarpus longan) with potassium chlorate has improved the availability of longan fruit, but potassium chlorate is potentially explosive and often difficult to purchase, transport, and store. Previous reports suggested that hypochlorite enhances natural longan flower induction. This study is the first to demonstrate that chlorite- and hypochlorite- (bleach) induced off-season longan flowering is similar to chlorate-treated trees. Hypochlorite induction of flowering with bleach was likely the result of chlorate in the bleach solution. Chlorate was present in the leachate from potted longan trees treated with bleach and was detected in bleach before soil application. The quantity of chlorate found in bleach induced flowering to the same or greater extent as equivalent quantities of potassium chlorate, suggesting chlorate is an a.i. responsible for longan flowering.

Originally discovered as the a.i. in fireworks gunpowder, KClO3 is a strong oxidizing agent responsible for the explosive nature of fireworks (Yen, 2000; Yen et al., 2001). Potassium chlorate is an extremely useful tool to effectively plan flowering and fruiting of longan trees for market. However, the dangers associated with large quantities of this chemical make it difficult to obtain and store; a mixture of KClO3 and sulfur was responsible for an explosion at a longan processing plant in Chiang Mai, Thailand, killing 35 workers and injuring over 100. Lack of personal protection equipment during prolonged use of KClO3 by Thai longan workers resulted in increased levels of anemia, thrombocytopenia, high serum creatinine, and methemoglobinemia, which are hypothesized to be related to KClO3 toxicity (Wiwatanadate et al., 2001).

Flowering of trees at the WRS treated with KClO3, NaClO2, bleach, and bleach plus CuCl2 began 5 weeks (22 Oct. 2004) after treatment. By 12 weeks after treatment, trees stopped production of panicles and the number of flowering terminals was determined. Nontreated control trees did not flower and KClO3, NaClO2, bleach, and bleach plus CuCl2-treated trees exhibited 97.8% (484 flowering/495 total terminals), 91.8% (462 flowering/503 total terminals), 84.7% (326 flowering/385 total terminals), and 96.9% (493 flowering/509 total terminals) flowering, respectively. The means for each treatment were not significantly less than the KClO3 treatment (P > 0.27) for NaClO2, bleach (P > 0.18), and bleach plus CuCl2 (P > 0.43) as analyzed by SAS PROC GLIMMIX using Dunnett's adjustment for multiplicity. This demonstrates that chlorate, chlorite, and hypochlorite can effectively induce off-season flowering of longan.

Investigation into the mechanism of chlorate toxicity by Åberg suggested that the chlorate toxicity is incited by reduction of chlorate to chlorite and hypochlorite by nitrate reductase (reviewed by LaBrie et al., 1991). As predicted by Åberg, the majority of plant nitrate reductase enzymes reduce chlorate to the toxic chlorite. Chlorate was used extensively in the past as an herbicide to control problematic weeds such as bindweed (Latshaw and Zahnley, 1927; Loomis et al., 1933; Neller, 1930) and is the a.i. in many herbicides used today (Bennett and Shaw, 2000). Chlorate has also been useful in the isolation of mutants with reduced nitrate uptake or impaired nitrate reductase activity (Crawford and Forde, 2002; Crawford and Glass, 1998; LaBrie et al., 1991; Meyer and Stitt, 2001). Nitrate reductase activity in leaves is reduced in longan trees treated with soil applications of KClO3, NaClO2, and bleach (Matsumoto et al., in press).

Hypochlorite enhances flowering in longan similar to potassium chlorate (Sritontip et al., 2005a), and we demonstrate that it can also effectively induce off-season flowering. NaOCl degradation occurs through two pathways. The first pathway leads to the production of oxygen, whereas the second leads to chlorate formation (Adam and Gordon, 1999). The incorporation of copper (Cu2+) to the bleach solution, an ion that catalyzes both degradation pathways of hypochlorite to chlorate or oxygen (Adam and Gordon, 1999), appeared to induce flowering to the same degree as KClO3 treatment or bleach treatments alone, suggesting chlorate in bleach contributed to the promotion of longan flowering.

Trees treated on 18 May 2005 began flowering 8 weeks after treatment (8 Aug. 2005) and produced new panicles until 16 weeks after treatment. No significant differences in flowering were found between the north and south tree faces for all treatments. Bleach-treated trees flowered at 54.9% (118 flowering/215 total), which is significantly less (P = 0.048) than the 300 g KClO3 treatments in which 94.0% (221 flowering/235 total) of the terminals flowered, but the bleach treatment was not significantly different (P = 0.406) compared with 67.9% (142 flowering/209 total) of the terminals flowering in trees treated with 45 g KClO3. This suggests that the chlorate in the bleach may be responsible for flower induction in longan.

Trees treated on 16 Sept. 2005 began flowering 7 weeks after treatments (4 Nov. 2005) and actively produced new panicles until 12 weeks (8 Dec. 2005) after treatment (Fig. 1). Flowering on the north and south faces of the trees was not significantly different for 250 g KClO3 (P = 0.926) or 2 gal bleach (P = 0.783); however, flowering was significantly different for the 50 g KClO3 treatment (P = 0.003). This difference in the flowering observed between the different faces of the trees treated with 50 g KClO3 may be attributed to the uneven distribution of chlorate on the soil under the tree canopy. Overall flowering of the trees treated with bleach was 97.1% (297 flowering/306 total terminals), which was not significantly different (P = 0.501) than trees treated with 250 g KClO3 in which 96.4% (318 flowering/330 total) of the terminals flowered but was significantly greater (P = 0.004) than flowering on trees treated with 50 g KClO3 in which 68.7% (237 flowering/345 total) of the terminal flowered.

In addition to hypochlorite and chlorate, sodium was also added to the soil during the bleach treatment. Soil analyses from trees treated with bleach and control trees at Onomea showed that at 14 weeks after treatment, soil from bleach-treated trees contained 151.3 36.8 ppm of Na+, whereas soil from untreated control trees contained 37.7 2.9 ppm of Na+. Soil pH and salinity were not significantly different in soil samples from bleach-treated and untreated trees and no visible signs of sodium toxicity could be detected. One year after bleach treatment, there was no significant difference between soil samples of bleach-treated trees, 24.4 2.9 ppm, and untreated trees, 24.3 4.8 ppm, suggesting that sodium did not accumulate in the soil. 041b061a72

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