Citric acid thiocyanates

Dithiol is a less selective reagent than thiocyanate for molybdenum. Tungsten interferes most seriously but does not do so in the presence of tartaric acid or citric acid (see Section 17.34). Tin does not interfere if the absorbance is read at 680 nm. Strong oxidants oxidise the reagent iron(III) salts should be reduced with potassium iodide solution and the liberated iodine removed with thiosulphate. 

Supplement (combined with Volume IV) III, 2nd 1929 195-449 Hydroxy-carboxylic acids Carbonic acid, 3. GlycoUic acid, 228. Lactic acid, 261. Tartaric acid, 481. Citric acid, 556. Urea, 42. CyS namide, 74. Thiocyanic acid, 140. 

The aqueous process solution containing sodium thiocyanate with impurities was provided by a local industry. All the membrane modules, pressure vessels, and accessories for the nanofiltration pUot plant used in this study were purchased from Permionics Membranes Pvt. Ltd. (Baroda, India) and assembled in the laboratory. Citric acid, tetra sodium salt of ethylene diamine tetraacetic acid (EDTA), trisodium phosphate (TSP), and sodium metabisulfite for cleaning and maintenance of the membranes were procured from Lob a Chemie (Mumbai, India). 

The indium chloride complex can be extracted from 1-4 M HCl with TO A in chloroform or 1,2-dichloroethane [8], or with n-octylaniline in CHCI3 [9]. From acidic thiocyanate media, indium has been extracted with tetra-n-hexylammonium salt in 1,2-dichloroethane [10], or with 15% TBP in kerosene [11]. Indium has been extracted also with Aliquat 3368 in xylene from 0.01 M citric acid medium [12]. 

Determination of Mo. Add 20 ml of weakly acidic sample solution (HCl, H2SO4), containing not more than 50 of Mo, to a separating funnel. Add successively 3 ml of cone. HCl, 3 ml of 20% citric acid solution, 1 ml of Fe(III) solution, 3 ml of thiocyanate solution, and, with swirling, 3 ml of SnCh solution. After 5 min, shake the solution with two portions of isoamyl alcohol. Make up the combined extracts to the mark with the solvent in a 25-ml standard flask, and measure the absorbance at 470 nm, using the solvent as reference. 

Among the other notations is that acetaldehyde is to be avoided, it being a respiration inhibitor. It is related to ethyl alcohol or ethanol and also to acetic acid, but not necessarily to citric acid as involved in the carboxylic acid or citric acid cycle. Alkaloids are expectedly respiration inhibitors, and anesthetics can have respiration inhibition as a side effect. Aromatic adds such as phenol are bad news, as are arsenate, cyanide, isothiocyanate, and thiocyanate. The heavy metals cadmium, cobalt, copper, ruthenium, vanadate, and zinc are regarded as health risks, if not for respiration, for other reasons. 

LEAD DINITRATE (10099-74-8) Pb(N03)2 Noncombustible solid. A strong oxidizer accelerates burning of combustible materials. Violent reaction, or may form explosive materials, with reducing agents, including hydrides, nitrides, phosphoms, stannous chloride, and sulfides alkyl esters (forms explosive alkyl nitrates) combustible materials, potassium hexanitrocobalite(III) (C. I. pigment yellow), cyclopentadienyl sodium, red hot carbon, lead(II) phosphinate, phosphoms, tin(II) chloride. Incompatible with aluminum, ammonia, ammonium thiocyanate (mixture forms the shock- and friction sensitive explosive guanidine nitrate) citric acid, hydrozoic acid, metal phosphinates, methyl isocyanoacetate, sodium peroxyborate, potassium acetate. 

HEXAHYDRATE (10377-60-3) A powerful oxidizer. Reacts violently with dimethyl-formamide, reducing agents, combustible materials, fuels, organic substances, metal powders, potassium hexanitrocobalite(III) (C.I. pigment yellow), sodium acetylide, and easily oxidizable matter. Incompatible with aluminum, ammonium hexacyanoferrate(II), tert-butylhydroperoxide, citric acid, ethanol, ferrocyanides, hydrazinium perchlorate, isopropyl chlorocarbonate, metal phosphinates, nitrosyl perchlorate, organic azides, phosphorus, sodium thiosulfate, sulfamic acid, thiocyanates, tin(II) fluoride, and many other substances. 

MERCURIC NITRATE (10045-94-0) A powerful oxidizer. Violent reaction with reducing agents, combustibles, phosphinic acid, hypophosphoric acid, petroleum hydrocarbons. Forms heat- and/or shock-sensitive compounds with acetylene (forms mercury acetylide), ethanol (forms mercury fulminate), ferrocene, isobutene, phosphine, potassium cyanide, sulfur. Incompatible with strong acids, acetic anhydride, ammonia, ammonium hexacyanofer-rate(II), organic azides, citric acid, hydrazinium perchlorate, isopropyl chlorocarbonate, nitrosyl perchlorate, sodium thiosulfate, sulfamic acid, thiocyanates, hydrozoic acid, methyl isocyanoacetate, sodium peroxyborate, trinitrobenzoic acid, urea nitrate. Aqueous solution corrodes metals. 

NITRATO de ZINC (Spanish) (7779-88-6) Noncombustible, but will enhance the combustibility of other materials. Many chemical reactions can cause fire and explosions. A strong oxidizer. Violent reaction with reducing agents, strong oxidizers, combustible materials, organic substances, metallic powders, acetic anhydride, /err-butylhydroperoxide, carbon, di-methylformamide, metal cyanides, metal sulfides, phosphorus, sodium acetylide, sulfur, thiocyanates. Incompatible with amines, ammonium hexacyanoferrate(II), boranes, cyanides, citric acid, esters, hydrazinium perchlorate, isopropyl chlorocarbonate, nitrosyl perchlorate, organic azides, organic bases, sodium thiosulfate, sulfamic acid. Attacks metals in the presence of moisture. 

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