Analysis of First Mother Liquor

Analysis of First Mother Liquor A613 R Analysis of Second Mother Liquor A615-L Analysis of First Clear Liquor A615-L Analysis of Lime Treatment Tank A615-R Analysis of Second Clear Liquor A616-L Analysis of Crude Sodium Azide Liquor A616-L... 

V )First Mother Liquor is the liquid wrung from one evaporator chge (See under Manufacture of Sodium Azide) of normal or average analysis NaOH (actual) 34.4%, NaN (actual) 2.5% and NaaCOj (actual) 0.2%. A 25-ml sample was dipped by hand from the catch tank after the charges had been centrifuged and all samples composited for one week. At the end of each month, an 8-oz sample was taken, from the storage tank for monthly in-ventory and was analyzed in the same way as the weekly composites... 

IX)Lime Treatment Tank contained liquor obtained from the wringer producing the second wringer cake. The liquor normally contained ca 9-10% NaN, 10-13% NaOH and up to 0.75% Na2C03. Its sp gr by hydrometer was ca 1.2. An 8-oz sample was taken,and after analysis according to item VI (First Mother Liquor), the amt of iime necessary to ppt the carbonate as CaCOj was calcd and... 

Analyze the first crop of triphenylmethanol and the residue from the evaporation of the mother liquors by thin-layer chromatography. Dissolve equal quantities of the two solids (a few crystals) and also biphenyl in equal quantities of dichloromethane (1 or 2 drops). Using a microcapillary, spot equal quantities of material on silica gel TLC plates (Eastman No. 13181) and develop the plates in an appropriate solvent system. Try 1 3 dichloro-methane-petroleum ether first and adjust the relative quantities of solvent as needed. The spots can be seen by examining the TLC plate under a fluorescent lamp or by treating the TLC plate with iodine vapor. From this analysis decide how pure each of the solids is and whether it would be worthwhile to attempt to isolate more triphenylmethanol from the mother liquors. 

Halide impurities are probably the most studied of the four general categories of impurities common to ionic liquids and, besides electrochemical analysis, two methods are currently being used to determine the level of residual halide impurities in ionic liquids [12]. The titration of the ionic hquid vnth AgN O3 is still widely used but suffers from a certain solubility of AgQ in the ionic hquid under investigation. This method can be enhanced by the Vollhard method for chlorine determination where the chloride is first precipitated with excess AgNO3 followed by back-titration of the mother liquor with aqueous potassium thiocyanate [13]. This method uses a visual endpoint through the formation of a complex between thiocyanate and an iron (III) nitrate indicator. 

Sampling and characterization. 10 ml samples, including liquid and solid phases, were withdrawn periodically from the autoclave during the crystallization. The slurries were collected in 70 ml of cold deionized water. The solid fraction was recovered by filtration and washed first with 250 ml of water. The clear solution, containing the diluted mother liquor, was preserved for chemical analysis. After additional washing (up to a pH of 9), the solid was dried at 70°C in air. 

The mother liquor of the last bond-forming step and first recrystallization are recommended for inclusion in the KPSS. Analysis of both these samples can reduce the KPSS versus that based on a single mother liquor. 

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