Showing papers on "Potassium iodate published in 2007"

Synthesis, characterization and ion exchange properties of zirconium(IV) tungstoiodophosphate, a new cation exchanger

Abstract: Zirconium(IV) tungstoiodophosphate has been synthesized under a variety of conditions. The most chemically and thermally stable sample is prepared by adding a mixture of aqueous solutions of 0·5 mol L−1 sodium tungstate, potassium iodate and 1 mol L−1 orthophosphoric acid to aqueous solution of 0·1 mol L−1 zirconium(IV) oxychloride. Its ion exchange capacity for Na+ and K+ was found to be 2·20 and 2·35 meq g−1 dry exchanger, respectively. The material has been characterized on the basis of chemical composition, pH titration, Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis. The effect on the exchange capacity of drying the exchanger at different temperatures has been studied. The analytical importance of the material has been established by quantitative separation of Pb2+ from other metal ions.

Studies in kinetics and mechanism of oxidation of d-glucose and d-fructose by alkaline solution of potassium iodate in the presence of Ru(III) as homogeneous catalyst

Abstract: Kinetics of oxidation of d -glucose (glc) and d -fructose (fru) by potassium iodate has been studied for the first time in alkaline medium using Ru(III) as homogeneous catalyst. The linear dependence of the reaction rate at lower [IO 3 − ] and [OH − ] tends towards zero-order at their higher concentrations. Experimental results also show that the order with respect to [Ru(III)] is unity and the order with respect to [reducing sugar] is zero in the oxidation of both glc and fru. Variation in [Cl − ] and ionic strength ( μ ) of the medium does not affect the oxidation rate. The species, [RuCl 2 (H 2 O) 2 (OH) 2 ] − and IO 3 − , were found to be the reactive species of Ru(III) chloride and potassium iodate in alkaline medium, respectively. The reactions have also been studied at four different temperatures and with the help of observed values of pseudo-first-order rate constant ( k 1 ), the entropy of activation and other activation parameters have been calculated. A common mechanism, where the rate determining step involves the interaction between reactive species of Ru(III) chloride and reactive species of potassium iodate resulting in the formation of an activated complex, Download full-size image has been proposed. The formation of activated complex is very well supported by the spectrophotometric evidence, observed kinetic data and also by the negative entropy of activation observed for the oxidation of both glc and fru. Arabinonic acid and formic acid were identified as the main oxidation products of the reactions.

A sensitive spectrophotometric method for the determination of arsenic in environmental samples

Abstract: We developed a cost-effective and sensitive spectrophotometric method for the determination of arsenic at trace level using a new reagent, leuco malachite green Here we show that, arsenic reacts with potassium iodate in acidic conditions to liberate iodine, and the liberated iodine selectively oxidizes leuco malachite green to malachite green dye We studied the Beer’s law at 617 nm, which showed linearity over the concentration range 009–09 μg ml−1 of arsenic We show that the molar absorptivity, Sandell’s sensitivity and detection limit of the method are 61 × 104 l mol−1 cm−1, 00012 μg cm−2 and 0025 μg ml−1, respectively We applied the developed method for the determination of arsenic in environmental samples

Confirmation of polymerisation effects of sodium chloride and its additives on acrylamide by infrared spectrometry

Abstract: Summary Acrylamide was applied onto two additives of table salt - potassium ferrocyanide and potassium iodate - and heated in a glass reaction vessel within temperature range 102–180 °C with heating rate of 2 °C.min -1 to study the effect of these inorganic salts on acrylamide elimination. For comparison, the same experiment was carried out also with chemically pure sodium chloride. As found, the amount of acrylamide applied onto chemically pure sodium chloride decreased only by 13%, while the amounts of acrylamide applied onto potassium ferrocyanide and potassium iodate decreased much more considerably - by 61% and 88%, respectively. Comparing infrared spectra of pure acrylamide and the product formed during the experiments, it was found that all the salts under study brought about the polymerization of acrylamide through the formation of C-C backbone polymer while the carbonyl and amino groups remained unchanged. As concluded, potassium ferrocyanide and potassium iodate exhibit a much stronger effect on acrylamide polymerization than pure sodium chloride itself. For this reason, they could strengthen considerably the efficiency of acrylamide elimination in a real food matrix with regard to their presence in table salt, or being added directly to the thermally treated food matrix, respectively.

Retention of iodine in fortified parboiled rice and its pasting characteristics during storage

Abstract: Iodine fortification, as potassium iodide (KI) or potassium iodate (KIO 3 ), in parboiled milled rice was investigated. The fortified parboiled milled rice (9-10% moisture content) contained 11.6 X 10 -2 mol KI per 100-g salt or 9 x 10 -2 mol KIO 3 per 100-g salt. The iodine-fortified parboiled milled rice after dialysis retained 80.50-84.87% iodine, while the milled rice retained 97-100% iodine in the samples. Test on in vitro starch digestion showed that most iodine was released within 15 min of starch digestion. The iodine-fortified and nonfortified parboiled milled rice showed significant higher pasting temperature, peak time and setback viscosity than normal milled rice. After storage for 5 months, iodine content in fortified parboiled milled rice decreased significantly (P < 0.01), while iodine content in milled rice did not change during storage. For the rice stored at ambient temperature, the rapid visco-analyzer amylograph viscosity (peak viscosity, trough viscosity and final viscosity) increased during the first 2 months and decreased during storage. Iodine did not affect these attributes of parboiled milled rice.

Rapid titrimetric and spectrophotometric assay methods for the determination of lamivudine in pharmaceuticals using iodate and two dyes

Abstract: One titrimetric and two spectrophotometric methods, which are simple, sensitive and rapid, are described for the assay of lamivudine in bulk drug and in tablet dosage forms using potassium iodate and two dyes, methyl orange and indigocarmine, as reagents. In titrimetry, an aqueous solution of lamivudine is titrated directly with iodate in an acidic medium, and in the presence of an excess of bromide using methyl orange as an indicator. After the decoloration of the red color of methyl orange, the residual bromine is titrated iodometrically to a starch endpoint. Spectrophotometric methods involve the addition of a known excess of iodate in an acidic medium and in the presence of an excess of bromide followed by the determination of residual bromine by the reaction with a fixed amount of either methyl orange and measuring the absorbance at 520 nm (method A), or indigo carmine and measuring the absorbance at 610 nm (method B). In all methods, the amount of iodate which reacted corresponds to the amount of lamivudine content. The titrimetric method is applicable over the 1.5–8.0 mg range. The systems obey Beer’s law for 0.5–5.0 µg/mL (method A) and 1.25–12.5 μg/mL (method B). The calculated apparent molar absorptivity values are found to be 3.3 × 104 and 9.3 × 103 L mol−1 cm−1, for method A and method B, respectively, and the corresponding Sandell sensitivity values are 6.94 and 24.62 ng/cm2. The limits of detection and quantification are also reported for both spectrophotometric methods. Intra-and interday precision and accuracy for the developed methods have been evaluated. The methods were successfully applied to the assay of lamivudine in tablet form and the results were compared with those of a reference method by applying the Student’s t-test and F-test. No interference was observed from common tablet adjuvants. The accuracy and reliability of the methods were further ascertained by recovery experiments using the standard addition technique.

Potassium iodate–initiated polymerization of aniline

Abstract: Potassium iodate–initiated polymerization of aniline was carried out in an acidified aqueous medium in the presence and in the absence of sodium thiosulfate salt. The nature of the polyaniline (PANI) produced depended on the aniline/potassium iodate (A/PI) mole ratio. Green emeraldine salt (ES) and blue pernigraniline salt (PS) were produced at A/PI mole ratios greater than 2 and less than 2, respectively. The sodium thiosulfate salt played a significant role in the purification and properties of PANI. The optimum aniline-to-oxidant mole ratio was found to be 2 : 1. Spectral, thermal, and electrical characteristics and viscosity of the materials were studied and compared with the results. A reaction scheme has been proposed to elucidate the role of iodine(V). Sodium thiosulfate makes it easier for iodine to be separated from a system and increases the conductivity of the products. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 1626–1631, 2007

Green health iodic salt

Abstract: The green health iodized salt belongs to the field of food product technology The green health iodized salt has refined kelp and seaweed powder as iodine source to replace traditional potassium iodate and potassium iodide The present invention changes the inorganic iodide in table salt into organic iodide and can raise the iodine ingesting amount by two times Kelp and seaweed have high iodine content and the organic iodide is chemically stable, so that adding the refined kelp and seaweed powder in the amount of 25 wt% into table salt can meet the iodine replenishing requirement At the same time, kelp and seaweed contains also many trace elements and amino acids essential for human body The refined kelp and seaweed powder is produced with kelp and seaweed and through depurating, washing, crushing, milling into powder, sterilizing, adding preservative and packing

Stability of iodinated salts during roasting and storage of pork meatballs

Abstract: The objective of the study was to determine the effect of table salt iodinated with potassium iodide or iodate added to chopped pork on the stability of iodine during roasting and chilled or frozen storage. During thermal processing (roasting), and chilled or frozen storage of meatballs, better stability was found for iodine introduced along with salt iodinated with potassium iodate. Roasting of meatballs for 15 min resulted in a 5% loss of iodine. Extension of thermal treatment to 30 min resulted in an increase, almost threefold, of iodine loss. Along with the extension of chilled or frozen storage of meatballs a disadvantageous effect of a longer thermal processing was observed on the stability of iodine introduced along with iodinated salt. However, in the case of table salt iodinated with potassium iodide, better iodine retention was observed during storage of samples heated with an applied longer thermal treatment time in comparison to table salt iodinated with potassium iodate.

Method for synthesizing 4,4-didetergent alkylate iodonium hexafluoro antimonate

Abstract: The present invention relates to a synthesizing method for 4,4 double hexabromocyclododecane alkyl benzene iodine fluorin antimonite, which is made with the following steps: (1) 4,4 double hexabromocyclododecane alkyl benzene iodine is prepared by the reaction with barium chloride under the function of vitriol taking detergent alkylate and potassium iodate as the material, and acetic anhydride as the solution; (2) 4,4 double hexabromocyclododecane alkyl benzene iodine fluorin antimonite is prepared by the ion reaction between 4,4 double hexabromocyclododecane alkyl benzene iodine and fluorin potassium metaantimonate in cyclohexane, chloroform or dichloroethane solution agent. The 4,4 double hexabromocyclododecane alkyl benzene iodine fluorin antimonite synthesized by the present invention has much better solidified performance to the resin.

Method for preparing potassium iodate and potassium iodide

Abstract: FIELD: inorganic chemistry, chemical technology. ^ SUBSTANCE: invention relates to a method for preparing potassium iodate and potassium iodide. Potassium hydroxide, iodine and water are added to reactor, reaction mixture is stirred and formed suspension of crude iodate with admixture of potassium iodide in potassium iodide solution with admixture of potassium iodate is cooled. Crude iodate precipitate is separated and purified. The main part of potassium iodate in potassium iodide solution is reduced with formic acid to potassium iodide and residual amount of potassium iodate and iodine is reduced additionally in potassium iodide solution. Purification of crude potassium iodate from admixture of potassium iodide is carried out by electrochemical oxidation and addition reduction of potassium iodate and iodine is carried out with a measured amount of hydrazine hydrate. If necessary, equivalent amount of iodine and hydrazine hydrate are added for decreasing the alkalinity index of solution. Invention provides simplifying technology in preparing potassium iodate, simplifying technology and enhancing effectiveness in preparing potassium iodide, increased output of used equipment and reducing energy consumption. Potassium iodide and potassium iodate are used in pharmaceutical industry as components of medicinal agents, in food processing industry, in producing photographic materials and reagents and for other aims. ^ EFFECT: improved method for preparing. ^ 3 ex

Determination of Potassium Iodate by Resonance Rayleigh Scattering Method with Ethyl Violet

Abstract: In H3PO4 solution, potassium iodate reacts with potassium iodide to form I-3, which further interacts with ethyl violet to form ion-association complexes. This results in significant enhancement of intensity of the resonance Rayleigh scattering (RRS) and the appearance of a new RRS spectrum. The maximum RRS peak is located at 319 nm, the intensity of RRS (ΔI) is directly proportional to the concentration of potassium iodate in the range of 2.33×10-3-3.00 μg·mL-1 and the detection limit is 0.7 ng·mL-1. The method has a good selectivity and can be applied to the determination of potassium iodate in table salt with satisfactory results.

Method for preparation of perfluoro-c4-c8alcyl halides

Abstract: FIELD: chemistry. ^ SUBSTANCE: invention refers to the method for preparation of perfluoro-C4-C8alcyl halides of general formula Rf X, where Rf - perfluoro-C4-C8alcyl, X - bromine, iodine, fluorine. The process includes the following stages: a) interreaction of the corresponding perfluoro-C4-C8alcane sulphonic-acid fluoride of general formula RfSO2F with hydrazine in the medium of organic solvent at temperature not less than 50C with obtaining of the corresponding perfluoro-C4-C8alcyl sulphonyl hydrazide with formula RfSO2NHNH2 and b) interreaction of the product obtained in the stage a) with corresponding elemental halogen at heating in the medium of organic solvent at temperature range 90-120C. The preferential solvent for stages a) and b) is N-methylpirrolidone; the elemental halogen used in the stages b) is bromine or iodine. In latter case the reaction is carried out in the presence of potassium iodate. ^ EFFECT: high yield and quality of the target product ^ 4 cl, 2 ex

Effect of different dosage potassium iodate on anti-oxidative capability of thyroid in rats

Abstract: Objective To study the effect of different dosage KIO3 on the thyroid anti-oxidative capability. Methods The rats were divided into 6 groups and given by different dosage of KIO3,those were low iodide (LI),normal iodide (NI),5 fold high iodide (5HI),10 fold high iodide (10HI),50 fold high iodide (50HI)and 100 fold high iodide (100HI),3,6 and 12 months later,the rats were sacrificed and thyroid glutathione peroxidase (GPx)activity,Superoxide Dismutase(SOD)activity and malondialdehyde (MDA)content were measured. Results The activities of GPx and SOD and the MDA content in LI group were markedly higher than those in NI group.There was no difference in the SOD and GPx activity among NI,5HI and 10HI groups.The GPx activity in 50HI and 100HI groups were lower than that in NI group after adminnistration for 12 months,but no difference between these three groups after treatment for 3 and 6 months.The SOD activity in 50HI and 100HI groups were lower than that in NI group after administration for 6 and 12 months,but no difference was found between them after treatment for 3 months.There was no difference in MDA content among NI group and 4 high iodide groups.Conclusion Low iodide intake would damage the anti-oxidative capability of thyroid in normal rats. Thyroid had a strong anti-oxidative ability and compensative acpabilities to compete with high dosage potassium iodate intake.

Reactions between solids. IV. Reaction of sodium perchlorate, potassium bromate and potassium iodate with polydivinylbenzene

Abstract: The kinetics of the solid–solid reaction between sodium perchlorate, potassium bromate and potassium iodate, with a cross-linked divinylbenzene/ethylstyrene copolymer (pDVB) was investigated. The two latter reactions were studied also in the presence of various additives, some of which acted as catalysts and others as inhibitors. All these reactions obeyed the empirical rate law proposed in the preceding paper. The effect of various additives and the mechanism of the reaction are discussed.

Study by scanning electron microscopy of mixture of cereal proteins fractions (maize and wheat) from bread doughs prepared at high temperature in the presence of oxidants.

Abstract: Protein from flour and doughs prepared at high temperature in presence and absence of oxidants (potassium bromate, potassium iodate and L-ascorbic acid) was fractionated according to solubility into water, salt, alcohol, acetic acid, soluble protein fractions and insoluble residue protein. All fractions were freeze-dried and subjected to scanning electron microscopy to observe visually the changes in protein structure. Acetic acid-soluble and insoluble residue protein are alike in structure, but the former was thermally denatured easily, while the latter was very stable to heat treatment. Salt and alcohol, soluble protein were not deformed, but the water soluble protein was deformed by heat treatment in the absence of oxidant. Oxidants generally promoted deformation of protein structure with the exception that bromate partly protected acetic acid-soluble protein from deformation.