Determination of Piperazine in Formulations by Nonaqueous Titration

1963 ◽  
Vol 46 (6) ◽  
pp. 1060-1062
Author(s):  
R B Maybury ◽  
R Payfer
Keyword(s):  
Aqueous Solution ◽  
Acetic Acid ◽  
Perchloric Acid ◽  
Glacial Acetic Acid ◽  
Chloroform Solution ◽  
New Method ◽  
Alternative Procedure ◽  
Good Agreement

Abstract A new method is presented for the nonaqueous titration of piperazine in formulations in which the piperazine base is first brought into aqueous solution, and the solution is made strongly alkaline and extracted with chloroform. The chloroform solution of piperazine is then titrated with acetous perchloric acid to alpha-naphthol benzein indicator. The procedure is rapid, shows good agreement with other methods, and is applicable to most kinds of piperazine formulations. An alternative procedure for piperazine adipate, citrate, or tartrate in powders is given, in which the compound is dissolved and titrated directly in glacial acetic acid.

Nonaqueous Titration of Halides of Nitrogenous Bases, Using Trifluoromethyl Sulfonic Acid

1986 ◽  
Vol 69 (4) ◽  
pp. 620-624 ◽  
Author(s):  
N Aziz Zakhari ◽  
K Artur Kovar
Keyword(s):  
Acetic Acid ◽  
Acetic Anhydride ◽  
Perchloric Acid ◽  
Sulfonic Acid ◽  
Glacial Acetic Acid ◽  
Visual Detection ◽  
Phenothiazine Derivatives ◽  
Solvent Systems ◽  
Anhydrous Acetic Acid

Abstract Trifluoromethyl sulfonic acid in glacial acetic acid has been compared with perchloric acid as a titrant in 4 solvent systems: glacial acetic acid, acetic anhydride, a mixture of both, and acetone. The comparison was limited to the determination of halides of nitrogenous bases with and without the use of mercury(II) acetate reagent. The results of the visual titrations showed that both acids are comparable tit rants. However, trifluoromethyl sulfonic acid proved to be superior to perchloric acid in potentiometric titrations carried out in acetic acid-acetic anhydride mixtures. Moreover, the nonoxidizing properties exhibited by trifluoromethyl sulfonic acid proved advantageous over perchloric acid in the visual detection of end points in the titration of phenothiazine derivatives in anhydrous acetic acid, using crystal violet indicator.

Rubber. XVIth Communication. The Method of A. R. Kemp for the Determination of the Iodine Number of Rubber

1934 ◽  
Vol 7 (3) ◽  
pp. 587-590
Author(s):  
Rudolf Pummerer ◽  
Hermann Stark
Keyword(s):  
Acetic Acid ◽  
Iodine Number ◽  
Carbon Disulfide ◽  
Glacial Acetic Acid ◽  
Chloroform Solution ◽  
Precise Information ◽  
Iodine Chloride ◽  
The Subject ◽  
Accessible Form

Abstract In a communication of Pummerer and Mann in 1929 on the determination of the iodine number of rubber by means of iodine chloride in chloroform solution, Fisher and Gray were erroneously mentioned as the originators of the method, because of the fact that these authors were the first to publish the method in accessible form. The fact was overlooked that Fisher and Gray state in a footnote that the method was not their own but was that of A. R. Kemp of the Bell Telephone Laboratories. We are greatly indebted to Kemp for calling to our attention the error, which also appears in our XIVth Communication. The first paper of Kemp on the subject appeared a year later, and contains precise information. Kemp worked with a solution of iodine chloride in glacial acetic acid and a solution of rubber in carbon disulfide at 0° C., and as long ago as 1927 he showed that rubber obtained by extraction of crepe with petroleum ether (b. p. 35–60° C.), and precipitation with alcohol according to the method of Weber, Caspari and Feuchter, gave very satisfactory iodine numbers of 99.43–99.76 per cent of the theoretical value. At 15–20° C. disturbing effects of substitution occurred.

Determination of Plant Hormone Indole-3-Acetic Acid in Aqueous Solution

2012 ◽  
Vol 25 (1) ◽  
pp. 303-307 ◽  
Author(s):  
Jana Bulíčková ◽  
Romana Sokolová ◽  
Stefania Giannarelli ◽  
Beatrice Muscatello
Keyword(s):  
Aqueous Solution ◽  
Acetic Acid ◽  
Plant Hormone ◽  
Indole 3 Acetic Acid

Reverse Phase Liquid Chromatographic Determination of Chlorophacinone and Diphacinone in Bait Formulations

1982 ◽  
Vol 65 (4) ◽  
pp. 927-929
Author(s):  
Brian R Bennett ◽  
Gregory S Grimes
Keyword(s):  
Acetic Acid ◽  
Glacial Acetic Acid ◽  
Chromatographic Determination ◽  
Reverse Phase ◽  
Target Concentration ◽  
External Standard ◽  
Liquid Chromatographic Determination ◽  
Phase Liquid ◽  
Liquid Chromatographic

Abstract Chlorophacinone and diphacinone are extracted at the 0.005% level from grain or paraffinized baits with glacial acetic acid. The target concentration is 0.01 mg/mL. The filtered supernate is chromatographed on a Partisil PXS ODS10/25 liquid chromatography column with premixed and degassed glacial acetic acid-tetrahydrofuran-water (14 + 2 + 9) and detected at 288 nm. The concentration is calculated by using an external standard. The recovery from spiked samples averaged 96.6% for both analytes. The response is linear from 0.001 to 0.040 mg/mL. The coefficient of variation of within-day replicates ranged from 1.1 to 2.5%.

Semiautomated Determination of Tridihexethyl Chloride in Meprobamate Tablets

1984 ◽  
Vol 67 (4) ◽  
pp. 677-678
Author(s):  
Ross D Kirchhoefer
Keyword(s):  
Aqueous Solution ◽  
Active Ingredient ◽  
Chloroform Solution ◽  
Semiautomated Method

Abstract A semiautomated method has been developed for the analysis of tablets containing tridihexethyl chloride in combination with meprobamate. The method is based on the USP assay for tridihexethyl chloride in tablets. The active ingredient is dissolved in water, the aqueous solution is mixed with buffer and dye solution, and the dye complex is extracted into chloroform. The absorbance of the chloroform solution is monitored at 408 nm. Results from the semiautomated method agree with I results for the USP method. Recoveries from authentic formulations I show no interference from the excipients tested.

Determination of Carbaryl Residues in Honey Bees

1965 ◽  
Vol 48 (4) ◽  
pp. 771-774
Author(s):  
D P Johnson ◽  
H A Stansbury
Keyword(s):  
Aqueous Solution ◽  
Acetic Acid ◽  
Quantitative Determination ◽  
Honey Bees ◽  
Methylene Chloride ◽  
Hydrolysis Product ◽  
Separate Analysis ◽  
Yellow Substance ◽  
Hydrolysis Of

Abstract A method has been developed for detecting residues of carbaryl (1-naphthyl methylcarbamate) as well as its hydrolysis product, 1-naphthol, in dead bees. The method is based on extraction of the bees with benzene, followed by a cleanup involving liquid partitioning and chromatography on Florisil. The quantitative determination involves hydrolysis of carbaryl to 1-naphthol and coupling of the latter with p-nitrobenzenediazonium fluoborate in acetic acid to form a yellow substance. For separate analysis, free 1-naphthol is separated from methylene chloride into a basic aqueous solution. The sensitivity of the method is about 0.1 ppm; recoveries averaged 85.6 ± 6.6% for 1- naphthol and 83.8 ± 2.7% for carbaryl.

Collaborative Study of Two New Methods for the Determination of Phosphorus in Fruits and Fruit Products

1970 ◽  
Vol 53 (3) ◽  
pp. 575-578
Author(s):  
Ben Estrin ◽  
Frederick E Boland
Keyword(s):  
Aqueous Solution ◽  
Satisfactory Agreement ◽  
Collaborative Study ◽  
Volumetric Method ◽  
Acid Solutions ◽  
Dilute Acid ◽  
New Methods ◽  
Molybdate Method ◽  
Good Agreement

Abstract A collaborative study was conducted to compare a spectrophotometric molybdovanadate method and the official gravimetric quinoline molybdate fertilizer method 2.025(b), slightly modified, with the official volumetric method 20.032. Six collaborating laboratories analyzed dilute acid solutions of the ash of 5 different kinds of fruit products and an aqueous solution containing only KH2PO4 by each of the 3 methods. Satisfactory agreement between laboratories and good agreement between methods were obtained. From the results of this collaborative study it appears that the quinoline molybdate and the molybdovanadate methods are more accurate and precise than the official volumetric method. It is recommended that both the spectrophotometric molybdovanadate method and the gravimetric quinoline molybdate method for the determination of phosphorus in fruits and fruit products be adopted as official first action.

Note on the Determination of Exchangeable Sodium in Soils

1930 ◽  
Vol 20 (3) ◽  
pp. 355-358 ◽  
Author(s):  
Rice Williams
Keyword(s):  
Acetic Acid ◽  
Ammonium Chloride ◽  
Uranyl Acetate ◽  
Exchangeable Sodium ◽  
Method Of Determination ◽  
Good Agreement

1. The application of the zinc uranyl acetate method to the determination of exchangeable sodium in soils is discussed.2. Using this method of determination, good agreement was found between the exchangeable sodium extracted by 0·5 N acetic acid and that extracted by N ammonium chloride.3. The procedure for estimating sodium in acetic acid extracts is described, and the results for a number of typical non-saline Welsh soils are given.

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