Hydrogen Peroxide In Alkaline Solution Research Articles

Separation of molybdenum from several interfering elements by tribenzy lamine extraction of its thiocyanate

A simple extraction of molybdenum for routine analysis is proposed. Molybdenum(VI) is reduced with hydrazine sulphate in 2 M hydrochloric acid. Fluoride is added to mask various metal ions, and the Mo(V)-thiocyanate complex is extracted by 1% tribenzylamine in chloroform. Molybdenum is back-extracted with an alkaline hydrogen peroxide solution. After suitable treatment, milligram amounts of molybdenum are determined by titration with cerium(IV) solution, and microgram amounts by spectrophotometry of the thiocyanate complex. The separation requires only about 20 min (< 10 min in series operation) and separates molybdenum from Ti, V, Cr, Mn, Fe, Co, Ni, Zr, Nb, W, Ce, Bi, U, Ru, Pb and Sb. The wide applicability of the method is shown by satisfactory analysis of a variety of synthetic samples for molybdenum.

The mechanism of the reaction between sodium peroxybenzoate and hydrogen peroxide in alkaline solutions

Sodium peroxybenzoate reacts with hydrogen peroxide to give sodium benzoate and oxygen: ▪ The O 2 originates from a molecule of hydrogen peroxide in experiments using sodium peroxybenzoate labelled with 18O at the peroxidic O atoms.

The formation of 1,2,4‐oxadiazoles from imidazoles by the action of hydrogen peroxide in alkaline solution

AbstractA hitherto unknown transformation of alkyl‐(aryl)‐imidazoles into alkyl‐(aryl)‐1,2,4‐oxadiazoles is described.

Decomposition of Dilute Hydrogen Peroxide in Alkaline Solutions

IN the development of an oxygen electrode for electrochemical fuel cells, it has been of interest to find effective catalysts for the decomposition of hydrogen peroxide in aqueous solutions of potassium carbonate and potassium hydroxide. We have compared the activity of fourteen catalytic solids.

Spectrophotometric determination of hydrogen peroxide in alkaline solution

A method of analysis of hydrogen peroxide in concentrations of about 10 −1 M, applicable to solutions which are stable towards alkaline hexacyanoferrate(III) and hexacyanoferrate(II), is suggested. The hydrogen peroxide is determined spectrophotometrically at 418 mμ from the decrease in absorbance it causes in a 1 × 10 −1 M potassium hexacyanoferrate(III) in 0·1 M potassium hydroxide.

The preparation and properties of a zirconium and hafnium peroxy compound

Zirconium and hafnium compounds dissolve in a cold alkaline solution of hydrogen peroxide from which solid of composition Na 2):Mo 2:O a:H 2O, 0·40:1·00:1·20:1·0, precipitates upon warming. The product takes up carbon dioxide with loss of peroxider to 0·8 O a/MO 2. The resulting product has an infra-red spectrum characteristic of basic carbonates. The products with or without carbonate exchange sodium for other actions.

The polarographic study of the formation of hydrogen peroxide in solutions of hydrazo-compounds in the presence of oxygen

It was found that in solutions of all compounds investigated containing the hydrazo group (hydrazobenzene, diphenylcarbazone, diphenylcarbazide and dithizone), hydrogen peroxide is formed in the presence of dissolved oxygen. The rate of the formation of hydrogen peroxide in alkaline solutions decreases in the following order : carbazone, hydrazobenzene, carbazide, dithizone, and increases from acidic to alkaline solutions. In acidic solution the formation of hydrogen peroxide occurs mainly with hydrazobenzene.

The reaction of ferriprotoporphyrin with hydrogen peroxide in alkaline solutions

The reaction of ferriprotoporphyrin (FPP) was studied in alkaline solutions. A stable iron porphyrin compound, FPP′, is formed when the reaction takes place in sodium hydroxide, sodium carbonate, or sodium bicarbonate solution, pH 7–13, but is not formed in the presence of pyridine. FPP′ was isolated free from FPP. The iron was removed to yield an ether-insoluble porphyrin. FPP′ was melted with resorcinol to give a compound spectroscopically similar to ferrideuteroporphyrin. From the reactions and spectroscopic properties, it was concluded that FPP′ is an oxidation product of FPP in which probably one or both of the vinyl side chains has been altered. It was further concluded that the iron atom is involved in this reaction.

Nonsilicate Stabilization of Hydrogen Peroxide Bleach Solutions

Alkaline solutions of hydrogen peroxide are stabilized by addition of calcium chloride and disodium phosphate. Evidence is given that stabilization may be due to the forma tion of CaHPO4 as precipitate.

Evaluation of Formaldehyde Pretreatment for Wool Bleaching

The formaldehyde treatment of wool fibers and fabric prior to bleaching by hot alkaline peroxide solutions has been investigated. Although pretreated fabrics exhibit lower alkali solubility and better handle after bleaching, characteristic degradation, shown by various single-fiber as well as fabric properties, is not retarded by the pre treatment. Formaldehyde pretreatment alone, under the conditions used, lowers the breaking stress and breaking extension of single fibers, but this degradation may not be severe enough to cause concern for many fabric uscs. Other experiments, without formaldehyde pretreatment, fail to support the claim that wool fibers possess increased susceptibility to damage when strained prior to bleaching.

AMINO ACIDS: IV. THE REACTION OF GLYCINE AND β-ALANINE WITH CARBON DISULPHIDE

Glycine and β-alanine on condensation with carbon disulphide gave the corresponding l,3-di-(carboxyalkyl) thioureas. l,3-Di-(carboxymethyl) thiourea is rearranged to 2-thio-3-(carboxymethyl) hydantoin by warming with hydrochloric acid solution or heating above its melting point. Evidence is presented for the reversible condensation of 2 mole equivalents of the sodium salt of 2-thio-3-(carboxymethyl) hydantoin by the elimination of water. This condensation product is obtained as well-defined pink crystals. l,3-Di-(β-carboxyethyl) thiourea was oxidized with an alkaline solution of hydrogen peroxide or sodium hypochlorite solution to l,3-di-(β-carboxyethyl) urea. l,3-Di-(β-carboxyethyl) thiourea and l,3-di-(β-carboxyethyl) urea have been cyclized by heating with p-toluenesulphonic acid. The products were 2-thio-3-(β-carboxyethyI) hydrouracil and 3-(β-carboxyethyl) hydrouracil respectively.

Oxidations with alkaline permanganate using monovalent thallium for the back titration: Estimation of hydrogen peroxide

Owing to the instability of hydrogen peroxide in alkaline solutions, direct oxidation with KmnO 4 did not yield accurate results.The back titration of KmnO 4 in the presence of IN NaOH and Ba +2 ions also gave inaccurate results. The reaction could not be checked at the manganate state. However, in the presence of 2 N NaOH and telluric acid quantitative data were obtained, which is not the case if telluric acid is absent. Another advantageous method is the oxidation of hydrogen peroxide with excess KmnO 4 in the presence of 1 N NaOH and telluric acid, followed by back titrating excess oxidant with monovalent thallium.

Stability of Dilute Alkaline Solutions of Hydrogen Peroxide

Stability of Dilute Alkaline Solutions of Hydrogen Peroxide

A new synthesis of menaphthone and lawsone

Based on biogenetic considerations new syntheses of menaphthone and lawsone are given. Fromα-naphthol, 1-hydroxy-4-methoxy-2-naphthaldehyde is prepared. This undergoes Clemmensen reduction and subsequent oxidative demethylation with nitric acid to yield menaphthone. On the other hand, Dakin’s oxidation gives directly lawsone and this change involves oxidative demethylation by hydrogen peroxide in alkaline solution. A convenient laboratory method for preparing lawsone employs 2-acetyl-α-naphthohydroquinone.

Reactivity of 4‐nitropyridine‐N‐oxide (II)): Substitution of the nitro‐group by hydroxyl)

AbstractWhereas 4‐nitropyridine‐N‐oxide is very stable towards dilute solutions of acids in water, its nitro‐group can be replaced by hydroxyl in a quick reaction by treating this substance with an alkaline solution of hydrogen peroxide in water at a temperature not surpassing 50°. This remarkable substitution reaction proceeds also when other 4‐substituted derivatives of pyridine‐N‐oxide and 4‐nitropyridine are reacted with the same reagent.

Quantitative determination of thiourea

Thiourea treated with alkaline solutions of hydrogen peroxide is converted to urea and the latter determined by means of urease. A procedure for the quantitative determination of thiourea in the presence of proteins and of urea is described. By this method thiourea can be determined in blood serum. The only substances found to interfere with the results were thiourca derivatives.

Emission spectra of some chemoluminescent reactions. Part I. The oxidation of dimethylbisacridinium nitrate

AbstractThe emission spectra of the chemoluminescent reaction between dimethylbisacridinium nitrate and hydrogen peroxide in alkaline solution have been determined at three different temperatures.At 94° the spectrum closely resembles the fluorescence spectrum of methylacridone, which is one of the end products of the reaction. It is however not completely identical with this spectrum as it is much broader.The hypothesis of Kautsky and Kaiser that the spectrum of the light emitted at room temperature is a combination of the high temperature spectrum and the fluorescence spectrum of dimethylbisacridinium nitrate has to be rejected. The spectrum at low temperature represents a second luminescent process. At 51° a spectrum is emitted which can be described as a combination of the spectrum at 94° and that at room temperature.In the determination of chemoluminescence and fluorescence spectra one has to account for the fact that part of the emitted light is absorbed by the reactants. A method is given to correct accurately for the influence of this phenomenon.

The colorimetric determination of nickel, chromium, and manganese in steel

With the aid of the Spckkei absorptiometer the colonmetnc delerminations, of nickel (with dimethylglyoxime), chromium (with diphenylcarbazide) and manganese (after oxidation with periodate) in steel were critically sinveyed The following factors were examined. wave length of the light, concentration of the reagents, stability of the coloured solution, temperature, influence of excess non, relation of extinetion coefficient and concentration of the coloured solution, influence of Mo, V, W, Ti, Al, Co, Cu, Ni, Cr, Mn, P and Si. For each determination a recommended procedure is given, with the results of control analyses. The recommended procedures are rapid. They can be used with steels of widely differing composition. The methods are accurate within 5% of the actual Value. 1. Nickle After neutrahsing the solution 5 ml (01 more) of concentrared ammonia (0.95) must be added. The temperature of the solution must be kept below 30° C before adding the dimethylglyoxime. The extinction coefficient is determined with light of 520 m/gm 2. Chromium The chromium is oxidised with hydrogen peroxide in alkaline solution. The influence of iron is ehminated by the addition of phosphoric acid. The recommended acidity is o.2 n, the quantily of diphenylcarbazide is 2 ml of a 1%'s solution in aceton. The determinations are made with a mercury lamp and filter (546 m/gm) 3. Manganese The solution of the sampie is boiled with ammoniumpersulphate and then oxidised with 300–500 mg of potassium periodate. The recommended acidity is 2 n, using a mixture of equal parts of sulphuric and phosphoric acids. The determinations are made with light of 520 m/gm.

Intensification of the latent image on photographic plates and films: II. The decomposition of hydrogen peroxide and the mechanism of latent image intensification

1. (1) It has been shown that, just as with pure alkaline and acid solutions of hydrogen peroxide and a metal catalyst, alkaline hydrogen peroxide in the presence of gelatin-silver or gelatin-silver sulphide sol, with or without the presence of soluble bromide, is much more easily decomposed than acid hydrogen peroxide under similar conditions. 2. (2) It has also been shown that both acid and alkaline solutions of hydrogen peroxide in the presence of soluble bromide react with silver sulphide, in bulk, to give sulphuric acid or a sulphate and colloidal silver bromide. 3. (3) Colloidal silver was found to dissolve to a greater or less extent in gelatin-hydrogen peroxide solution with a pII of 5.5 or less, giving rise to silver ions which when soluble bromide is also present form colloidal silver bromide. 4. (4) These facts indicate that intensification of latent image, and probably also the effect of hydrogen peroxide on sensitivity or the production of latent fog, is chemical in nature as Clark has contended and that a chemiluminescence mechanism while it has not been disproved is not necessary in order to explain the phenomenon. 5. (5) A chemical mechanism is proposed based on Hickman's recent theory of the formation of latent image by light. 6. (6) It is proposed that the bromine set free by the action of acid peroxide on the soluble bromide in the plate being very limited in quantity acts on the silver sulphide speck to form metallic silver, which in turn may be partly converted by the acid hydrogen peroxide into silver ions, and if any soluble bromide is left in the vicinity some colloidal silver bromide is formed containing on its surfaces adsorbed silver ions. It is believed that any one or all of these, metallic silver, silver ions, or colloidal silver bromide with silver ions adsorbed, produces a greater degree of developability of the grain than the original silver sulphide speck. 7. (7) This view is supported by the experimental fact that if soluble bromide is largely removed from a plate by action of silver nitrate (less than an excess), hydrogen peroxide produces very little if any intensification of latent image.

THE REACTIVITY OF THE METHYLATED SUGARS. I. THE ACTION OF ALKALINE HYDROGEN PEROXIDE SOLUTION ON TETRAMETHYL-d-GLUCOSE

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTTHE REACTIVITY OF THE METHYLATED SUGARS. I. THE ACTION OF ALKALINE HYDROGEN PEROXIDE SOLUTION ON TETRAMETHYL-d-GLUCOSEEdwin Lysle Gustus and W. Lee LewisCite this: J. Am. Chem. Soc. 1927, 49, 6, 1512–1521Publication Date (Print):June 1, 1927Publication History Published online1 May 2002Published inissue 1 June 1927https://doi.org/10.1021/ja01405a019RIGHTS & PERMISSIONSArticle Views32Altmetric-Citations6LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (612 KB) Get e-Alerts Get e-Alerts