Quaternary diffusion in aqueous potassium chloride-potassium dihydrogen phosphate-phosphoric acid mixtures

1987 ◽  
Vol 91 (6) ◽  
pp. 1655-1658 ◽  
Author(s):  
Robert A. Noulty ◽  
Derek G. Leaist
Keyword(s):  
Phosphoric Acid ◽  
Potassium Chloride ◽  
Potassium Dihydrogen Phosphate ◽  
Dihydrogen Phosphate ◽  
Potassium Dihydrogen

scholarly journals KH2PO4 crystallisation from potassium chloride and ammonium dihydrogen phosphate

2016 ◽  
Vol 18 (1) ◽  
pp. 1-8 ◽  
Author(s):  
Kristina Jančaitienė ◽  
Rasa Šlinkšienė
Keyword(s):  
Aqueous Solutions ◽  
Potassium Chloride ◽  
Solid Phase ◽  
Potassium Dihydrogen Phosphate ◽  
Molar Ratio ◽  
Dihydrogen Phosphate ◽  
Ammonium Dihydrogen Phosphate ◽  
Potassium Dihydrogen ◽  
Increasing Temperature ◽  
Nitrogen Phosphorus

Abstract Seeking to obtain bulk (NPK – nitrogen, phosphorus, potassium), chlorine-free fertilizers, the influence of interaction between potassium chloride and ammonium dihydrogen phosphate in aqueous solutions at temperature of 20, 40, 60 and 80°C has been investigated. Components of the solid phase have been identified by methods of chemical and instrumental analysis: radiography (X – ray), infra – red molecular absorption spectroscopy (IR) and scanning electron microscopy (SEM). It has been observed that the largest amount of solid state potassium dihydrogen phosphate was obtained at 60–80°C, when the potassium chloride and ammonium dihydrogen phosphate molar ratio is equal 0.8:0.2. Changing the molar ratio of 0.5:0.5 to 0.8:0.2, and with increasing temperature, various shaped crystals have developed in the remaining aqueous solutions with a morphology shifting from sharp needles to tetragonal prism.

scholarly journals Validated stability-indicating RP-HPLC method for simultaneous estimation of cilnidipine and chlorthalidone in tablet dosage form

2020 ◽  
Vol 11 (SPL4) ◽  
pp. 2435-2441
Author(s):  
Ashok B. Patel ◽  
Amitkumar J. Vyas ◽  
Shital Faldu ◽  
Arvind N Lumbhani ◽  
Nikunj J. Patel ◽  
...  
Keyword(s):  
Phosphoric Acid ◽  
Dosage Form ◽  
Potassium Dihydrogen Phosphate ◽  
Hplc Method ◽  
Simultaneous Estimation ◽  
Dihydrogen Phosphate ◽  
Potassium Dihydrogen ◽  
Rp Hplc ◽  
Tablet Dosage ◽  
Ich Guideline

A novel, simple, specific, accurate & precise stability-indicating Gradient reverse-phase high-performance liquid chromatography (RP-HPLC) method was developed for simultaneous estimation of Cilnidipine & Chlorthalidone in tablet dosage form, validated as per ICH guideline. The separation was achieved on Inertsil ODS column (250 mm x 4.6 mm, 5 μm) in a gradient mode.  The mobile phase consisted of Methanol, 0.025 M Potassium dihydrogen phosphate Buffer pH 5.5 adjusted by 10% v/v Ortho Phosphoric Acid (50:50 v/v) (Solution A) and Acetonitrile, 0.025 M Potassium dihydrogen phosphate Buffer pH 5.5 adjusted by 10%v/v Ortho Phosphoric Acid (75:25 v/v) (Solution B), gradient programming for 20 min at 1 ml/min rate of flow and response was detected at 225 nm. The retention time was found to be 3.580 min and 12.606 mins for Chlorthalidone and Cilnidipine, respectively. The method is validated according to ICH guideline, which includes linearity, specificity, accuracy, precision and robustness. Linearity was obtained over the concentration range of 10-60 μg/ml for Cilnidipine and 6.25-37.5 μg/ml for Chlorthalidone, had a regression coefficient (r2) almost 0.9966. The % Recovery was found to be 99.63-100.59 % and 100.24-100.51 % for Cilnidipine and Chlorthalidone, respectively. The method was found to be specific enough to separate all degradation products from the active compound. Drug samples were exposed to various stress conditions like photolysis, oxidation, heat conditions, and hydrolysis (acidic and alkaline), there was no interference of any degradants and excipient in the determination of drugs so that methods can be successfully applied for routine QC analysis.

Thermal diffusion of weak electrolytes: aqueous phosphoric and iodic acids

1990 ◽  
Vol 68 (8) ◽  
pp. 1317-1322 ◽  
Author(s):  
Lü Hui ◽  
Derek G. Leaist
Keyword(s):  
Phosphoric Acid ◽  
Thermal Diffusion ◽  
Potassium Dihydrogen Phosphate ◽  
Molecular Forms ◽  
Dihydrogen Phosphate ◽  
Potassium Iodate ◽  
Iodic Acid ◽  
Potassium Dihydrogen ◽  
Weak Electrolytes ◽  
Enthalpy Of Transport

Soret coefficients of aqueous phosphoric acid and aqueous iodic acid are determined conductimetrically at 25 °C. As the molality of phosphoric acid drops from 0.05 toward 0.00 mol kg−1, the enthalpy of transport jumps from 2 to 15 kJ mol−1. For iodic acid, a stronger electrolyte, the corresponding increase is smaller, from 12 to 17 kJ mol−1. Equations are developed for the enthalpy of transport of 1:1 weak electrolytes. The equations are used to evaluate the reactive enthalpy of transport and the intrinsic enthalpies of transport of the ionized and molecular forms of phosphoric and iodic acids. Equating the enthalpies of transport of the acid molecules and the acid anions provides estimates of single-ion enthalpies of transport. Thermal diffusion measurements are reported for potassium dihydrogen phosphate and potassium iodate to help interpret the results. Keywords: thermal diffusion, enthalpy of transport, Soret coefficients, weak electrolytes, phosphoric acid, iodic acid.

Note on the loss of phosphoric acid during fusion with ammonium fluoride

1916 ◽  
Vol 8 (1) ◽  
pp. 136-138
Author(s):  
William A. Davis ◽  
James Arthur Prescott
Keyword(s):  
Calcium Phosphate ◽  
Alkali Metal ◽  
Phosphoric Acid ◽  
Potassium Dihydrogen Phosphate ◽  
Ammonium Fluoride ◽  
Dihydrogen Phosphate ◽  
Hydrogen Phosphate ◽  
Disodium Hydrogen Phosphate ◽  
Potassium Dihydrogen ◽  
Considerable Loss

1. When salts or minerals containing phosphoric acid are ignited with ammonium fluoride as in the ordinary process of analysis of silicates, considerable loss of the phosphoric acid may occur. It is probable that the phosphorus is volatilised in the form of a phosphorus fluoride.2. The loss is least in the case of salts containing an alkali metal. It is less in the case of disodium hydrogen phosphate than in that of potassium dihydrogen phosphate, and is greatest in the case of phosphates of the alkali earth metals, such as calcium phosphate or apatite.

scholarly journals Optical Absorption Spectra of Vanadyl Ion (Impurities) in Three Host Crystal Compounds

1985 ◽  
Vol 40 (11) ◽  
pp. 1164-1166
Author(s):  
O. P. Agarwal ◽  
Prem Chand
Keyword(s):  
Optical Absorption ◽  
Potassium Dihydrogen Phosphate ◽  
Optical Data ◽  
Dihydrogen Phosphate ◽  
Host Crystal ◽  
Optical Absorption Study ◽  
Potassium Dihydrogen ◽  
Vanadyl Complexes ◽  
Vanadyl Ion ◽  
Magnesium Ammonium

Results of the optical absorption study of vanadyl ion doped in magnesium ammonium sulphate hexahydrate, rubidium sulphate and potassium dihydrogen phosphate single crystals at RT are reported. The nature of optical bands suggests a C4v symmetry of the Vanadyl complexes in conformity with the EPR results. Powder EPR data and optical data are correlated to obtain the MO coefficients.

scholarly journals The Strain Rate Sensitivity and Creep Behavior for the Tripler Plane of Potassium Dihydrogen Phosphate Crystal by Nanoindentation

Micromachines ◽  
2021 ◽  
Vol 12 (4) ◽  
pp. 369
Author(s):  
Jianhui Mao ◽  
Wenjun Liu ◽  
Dongfang Li ◽  
Chenkai Zhang ◽  
Yi Ma
Keyword(s):  
Strain Rate ◽  
Strain Rate Sensitivity ◽  
Creep Deformation ◽  
Potassium Dihydrogen Phosphate ◽  
Rate Sensitivity ◽  
Dislocation Nucleation ◽  
Machining Process ◽  
Dihydrogen Phosphate ◽  
Potassium Dihydrogen ◽  
Kdp Crystals

As an excellent multifunctional single crystal, potassium dihydrogen phosphate (KDP) is a well-known, difficult-to-process material for its soft-brittle and deliquescent nature. The surface mechanical properties are critical to the machining process; however, the characteristics of deformation behavior for KDP crystals have not been well studied. In this work, the strain rate effect on hardness was investigated on the mechanically polished tripler plane of a KDP crystal relying on nanoindentation technology. By increasing the strain rate from 0.001 to 0.1 s−1, hardness increased from 1.67 to 2.07 GPa. Hence, the strain rate sensitivity was determined as 0.053, and the activation volume of dislocation nucleation was 169 Å3. Based on the constant load-holding method, creep deformation was studied at various holding depths at room temperature. Under the spherical tip, creep deformation could be greatly enhanced with increasing holding depth, which was mainly due to the enlarged holding strain. Under the self-similar Berkovich indenter, creep strain could be reduced at a deeper location. Such an indentation size effect on creep deformation was firstly reported for KDP crystals. The strain rate sensitivity of the steady-state creep flow was estimated, and the creep mechanism was qualitatively discussed.

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