Potassium perchlorate, effect

An interesting case of selective oxidation in solution is given hy Jones,2 who has studied the absorption spectrum of a solution of uranous bromide in a mixture of water and methyl alcohol. Addition of potassium perchlorate effects an alteration in the absorption bands m such a manner as to show that the portion of the uranous salt combined with the methyl alcohol has undergone no change, whilst that united with the water has become oxidised. 

Mixtures of aluminium powder with liquid chlorine, dinitrogen tetraoxide or tetran-itromethane are detonable explosives, but not as powerful as aluminium-liquid oxygen mixtures, some of which exceed TNT in effect by a factor of 3 to 4 [1], Mixtures of the powdered metal and various bromates may explode on impact, heating or friction. Iodates and chlorates act similarly [2], Detonation properties of gelled slurries of aluminium powder in aqueous nitrate or perchlorate salt solutions have been studied [3], Reactions of aluminium powder with potassium chlorate or potassium perchlorate have been studied by thermal analysis [4],... 

When a thunderflash effect is required, a square of touch-paper is placed on the rear propellant surface inside the case at the opposite end to the choke, and a hairpin of safety fuse is placed inside the case in contact with the square of touch-paper. Some flash composition, based on potassium perchlorate, barium nitrate and aluminium, is then poured around the safety fuse and the head of the case is closed off with a pressing of clay or by simply being taped over. The all-important stick is... 

When potassium perchlorate is included in the composition, potassium ions are formed as seen in reactions (8.2) and (8.3). However, potassium emits in the near-IR region of the electromagnetic spectrum and so has little effect on the colour. On the other hand, the ionised form of Ba is undesirable since it emits in the blue region, and potassium salts are often added to Ba stars to suppress ionisation. 

Most flash and loud report effects are produced by using a relatively powerful oxidiser such as potassium perchlorate (which has a high available oxygen content), together with a hnely-divided metal fuel (M) that can react according to reaction (10.3). 

The perchlorate ion of potassium perchlorate, KCIO4, is a competitive inhibitor of thyroidal 1 transport via the Sodium Iodide Symporter (NIS).This drug can cause fatal aplastic anemia and gastric ulcers and is now rarely used. If administered with careful supervision, in limited low doses and for only brief periods, serious toxic effects can be avoided. The compound is especially effective in treating iodine-induced hyperthyroidism, which may occur, for example, in patients treated with the antiar-rhythmic compound amiodarone. Perchlorate ion can also be used in a diagnostic test of 1 incorporation into Tg, the so-called perchlorate discharge test. 

A feature of Bradyt F was the introduction of potassium perchlorate which increased the safety of the explosive by virtue of the potassium chloride formed on explosive decomposition. This proved effective in the experimental gallery. However, after being in use for many years, explosives of this type were withdrawn because of their comparatively high power (lead block expansion ca. 280 cm3) which was considered much too high for coal working, when more stringent regulations were introduced. 

Potassium perchlorate produces goiter, as do the thionamides, but its effects on the hematological system are the main reason for using it sparingly. 

Erythema nodosum associated with lupus erythematosus cells has been described as an adverse effect of potassium perchlorate (SED-8, 897) (1). 

The authors attributed these changes to an effect of amiodarone, but it is not clear that amiodarone-induced changes would have taken so long to become manifest after withdrawal. However, the diagnosis of type 2 amiodarone-induced hyperthyroidism was supported by a poor response to prednisone, potassium perchlorate, and methimazole. Lithium produced temporary benefit, but thyroidectomy was required. 

The treatment of amiodarone-induced hyperthyroidism is difficult. It often does not respond to conventional therapy with carbimazole, methimazole, or radio-iodine. However, corticosteroids and the combination of methimazole with potassium perchlorate have been reported to be effective (52), even if amiodarone is continued (53). Other regimens that have been used include combinations of corticosteroids with carbimazole (54), corticosteroids and benzylthiouracil (55), or propylthiouracil (SEDA-15, 170). Potassium perchlorate has also been used (SEDA-21, 199). Other forms of treatment that have been successful have been plasma exchange and in very severe cases subtotal thyroidectomy (56) or total thyroidectomy (SEDA-15,170 SEDA-17, 220 57). 

It has been suggested that potassium perchlorate should be used in the treatment of type 1 hyperthyroidism and glucocorticoids in the treatment of type 2 (SEDA-21, 199). Since hypothyroidism due to amiodarone tends to occur in areas in which there is sufficient iodine in the diet, it has been hypothesized that an iodinated organic inhibitor of hormone synthesis is formed and that the formation of this inhibitor is inhibited by perchlorate to a greater extent than thyroid hormone iodination is inhibited, since the iodinated lipids that are thought to be inhibitors require about 10 times more iodide than the hormone. However, there is a high risk of recurrence after treatment with potassium perchlorate, and it can cause serious adverse effects (SED-13,1281). 

Another non-equilibrium effect arises when the product composition contains a condensible substance. Solid propellant formulations based upon potassium perchlorate form solid potassium chloride and the acetylenic monopropellants upon decomposition form large quantities of carbon particles, as do very fuel-rich mixture ratios of hydrocarbon propellant systems. More recently metal and metal compounds have been used as fuels and form product oxides which are very high boiling point compounds that condense to varying degrees in the rocket chamber and nozzle. For example, estimates indicate that the normal boiling points of Li20, BeO,... 

While bromine itself can be used to effect a-bromination of ketones, the hydrogen bromide produced can be detrimental.The addition of acid scavengers such as 1,2-epoxycyclohexane (equation 1) 4 or potassium perchlorate can, however, lead to good yields in the more difficult cases. As with copper(II) salts, the conditions for elemental bromine also favor substitution at the more highly substituted carbon atom. 

SAFETY PROFILE An inhalation hazard. Mildly toxic by an unspecified route. An experimental teratogen. Experimental reproductive effects. A skin and eye irritant. Flammable in the form of dust when exposed to flame. The powdered metal may ignite on contact with air or oxidants (e.g., bromine pentafluoride, bromine, chlorine trifluoride, potassium perchlorate, potassium dichromate, nitryl fluoride, fluorine, oxygen difluoride, iodine pentafluoride, hydrogen sulfide, sodium peroxide, lead(IV) oxide). 

According to Dr.Osada the substance s,KCl, F8CI3, CuCl tf Cr Oj, K Cr Oy, LiCl etc., promote the decomposition of potassium perchlorate as in the case of chlorate. In particular Cr203 is very effective at lO c, and LiCl at 430 C, but these temperatures are a little higher than they would be with chlorateCJ. Industrial Exp. Society, Japan, p. 79i vol., No.6(1967)) ... 

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