NaClO

NaClO. Formed by heating NaClOa (see chlorates). Used to form perchlorates. 

Figure C2.10.3. Ex situ investigation of the electrochemical double layer on Ag after hydrophobic emersion from 1 M NaClO + 0.1 M NaOH. (a) Peak deconvolution of the XPS 01s signals after emersion at +0.2 V A surface...

The last example presented in this section deals with the pitting corrosion of Fe in CIO solutions. Perchlorate is less known as an aggressive ion but reveals some unique and remarkable characteristics with regard to pitting corrosion. For example, the critical pitting potential (1.46 V against a standard hydrogen electrode (SHE) for Fe/1 M NaClO ) can be measured with an accuracy of less than 4 mV [61] which is very unexpected if compared to... 

Heating with soda-dime. See Section 3, p. 327, Condense the aniline which distils over in a test-tube, dilute with water and add bleaching powder (or NaClO) solution. Note the iolet coloration. 

Special reactions — — — Fluores- cein Iodoform (KI + NaClO) FeSO, + H.O, + NaOH violet — — — (a) Fluores- cein W Phthalein —... 

Caustic soda solutions are normally tested for general alkalinity and percentages of NaCl, Na2S04, and NaClO as weU as for Fe and Ni levels. The general methods are outlined in Table 22. Detailed analytical methodologies are available from the major caustic soda suppHers. 

Success in the chlorine industry led to the incorporation of DSA in sodium chlorate [7775-09-9] NaClO, manufacture. The unique stmctural characteristics of the anode allowed for innovative designs in ceU hardware, which in turn contributed to the extensive worldwide expansion of the sodium chlorate industry in the 1980s. 

NaClO sodium hypochlorite NaC102 sodium chlorite NaClO sodium chlorate NaClO sodium perchlorate... 

Basic oxides of metals such as Co, Mn, Fe, and Cu catalyze the decomposition of chlorate by lowering the decomposition temperature. Consequendy, less fuel is needed and the reaction continues at a lower temperature. Cobalt metal, which forms the basic oxide in situ, lowers the decomposition of pure sodium chlorate from 478 to 280°C while serving as fuel (6,7). Composition of a cobalt-fueled system, compared with an iron-fueled system, is 90 wt % NaClO, 4 wt % Co, and 6 wt % glass fiber vs 86% NaClO, 4% Fe, 6% glass fiber, and 4% BaO. Initiation of the former is at 270°C, compared to 370°C for the iron-fueled candle. Cobalt hydroxide produces a more pronounced lowering of the decomposition temperature than the metal alone, although the water produced by decomposition of the hydroxide to form the oxide is thought to increase chlorine contaminate levels. Alkaline earths and transition-metal ferrates also have catalytic activity and improve chlorine retention (8). 

The alkah metal perchlorates are either white or colorless, and have increasing solubiUty in water in the order of Na > Li > NH4 > K> Rb > Cs. The high solubiUty of sodium perchlorate, NaClO, makes this material useful as an intermediate for production of all other perchlorates by double metathesis reactions and controlled crystallization. 

The U.S. domestic capacity of ammonium perchlorate is roughly estimated at 31,250 t/yr. The actual production varies, based on the requirements for soHd propellants. The 1994 production ran at about 11,200 t/yr, 36% of name plate capacity. Environmental effects of the decomposition products, which result from using soHd rocket motors based on ammonium perchlorate-containing propellants, are expected to keep increasing pubHc pressure until consumption is reduced and alternatives are developed. The 1995 price of ammonium perchlorate is in the range of 1.05/kg. Approximately 450 t/yr of NH ClO -equivalent cell Hquor is sold to produce magnesium and lithium perchlorate for use in the production of batteries (113). Total U.S. domestic sales and exports for sodium perchlorate are about 900 t/yr. In 1995, a solution containing 64% NaClO was priced at ca 1.00/kg dry product was also available at 1.21/kg. 

Hydrolysis constants for Pu(IV) have been determined in aqueous solutions at many pH values and ionic strengths. In 1 Af NaClO solution the first three Pu(IV) — OH complexes and overall stabiUty constants are (105) as follows ... 

Sodium Chlorite. The standard enthalpy, Gibbs free energy of formation, and standard entropy for aqueous chlorite ions ate AH° = —66.5 kJ/mol ( — 15.9 kcal/mol), AG = 17.2 kJ/mol (4.1 kcal/mol), and S° = 0.1883 kJ/(molK) (0.045 kcal/(molK)), respectively (107). The thermal decomposition products of NaClO, in the 175—200°C temperature range ate sodium chlorate and sodium chloride (102,109) ... 

Manufacture. Chloric acid is the precursor for generation of chlorine dioxide for pulp bleaching and other appHcations (see Bleaching agents), and is formed m situ by reaction of sodium chlorate [7775-09-9], NaClO, and a strong acid, eg. 

Densities of the NaClO —NaCl and KCIO —KCl aqueous solutions are given in Ref. 31. 

Product Specification. Sodium chlorate can be shipped either as soHd crystals or preblended chlorate—chloride solution. A typical specification for technical-grade sodium chlorate is NaClO, 99.5 wt % min NaCl, 0.12 wt % max moisture, 0.20 wt % max and 5 ppm chromium. 

Dichloroanthraquinone [82-46-2] (46) is an important iatermediate for vat dyes and disperse blue dyes. Examples are Cl Vat Violet 13 [4424-87-7] (170), Cl Vat Orange 15 [2379-78-4] (154), and Cl Disperse Blue 56 [31810-89-6] (11). 1,5-DichloroantliraquiQone is prepared by the reaction of anthraquiQone-l,5-disulfonic acid with NaClO iu hot hydrochloric acid solution. Alternative methods from 1,5-dinitroanthraquiaone (49) by reaction of chlorine at high temperature ia the presence of phthaUc anhydride have been proposed (66). 

Nearly 95% of the sodium chlorate produced ia North America is used to produce chlorine dioxide [10049-04-4] CIO2, for pulp (qv) bleaching (see Bleaching AGENTS, pulp and paper) (37). Minor amounts are used to produce other chemicals such as KCIO, NaC102, NaClO, etc, to recover uranium [7440-61-17, U (see Uraniumand uranium compounds) and for agricultural uses as a defoHant or herbicide (see Herbicides). 

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