Water-free products

As already mentioned above, the purity of the glycerine exerts a fundamental influence on the efficiency and safety of nitroglycerine manufacture. The so-called dynamite glycerine, a very pure water-free product, distilled several times under reduced pressure is produced for manufacture of nitroglycerine. 

After the desired carbon monoxide and steam flow rates were obtained and stabilized, the discharge was initiated. Operation of the unit was continued until product concentration in all six sample bottles (Figure 1) was uniform. The sample bottles were then isolated from the flow system and removed for analysis. The water-free product gases were analyzed by gas chromatography. 

A nonionic, water-free product which promotes good initial and long-term defoamlng as well as surface wetting properties. 

The following deals in particular with microbe-susceptible, water-containing raw materials and formulations. As a rule, water-free products lack the conditions necessary for micro-organism proliferation and are not discussed further in this chapter. 

On an industrial scale, the reaction in aqueous solution is a disadvantage because concentrated water-free products cannot be obtained without additional working-up steps. Therefore, a water-free process was developed, which is outlined in Fig. 44. The alkyl polyglycoside is initially introduced into the reactor with an excess of butyl chloride and heated to 80 °C. The reaction is initiated by addition of potassium hydroxide as the catalyst. On completion of the reaction, the reaction mixture is neutralized, the potassium chloride precipitate is filtered off, and the excess butyl chloride is distilled off. The product is composed of various alkyl polyglycosides and alkyl polyglyco-... 

Dry sizing Application of a melt-liquid, water-free product without a sticky component. 

Pan granulation of ammonium nitrate also has been developed commercially (16,17). Essentially water-free melt (<0.5%moisture) is sprayed onto a cascading bed of fines (usually cmshed recycle) ia a tilted, rotatiag pan. Production of 18—20 t/h is common. Product made ia this manner is said to require ao conditioning. The pan is an excellent size classifier, making it easy to produce granules of any desired size from 1 to 11 mm diameter. 

Hydrogen hahdes normally add to form 1,2-dihaLides, though an abnormal addition of hydrogen bromide is known, leading to 3-bromo-l-chloropropane [109-70-6], the reaction is beUeved to proceed by a free-radical mechanism. Water can be added by treatment with sulfuric acid at ambient or lower temperatures, followed by dilution with water. The product is l-chloro-2-propanol [127-00-4]. 

A solution of sodium methoxide, prepared from sodium (23 g) and dry methanol (500 mL), was added drop-wise at 0 °C to a stirred suspension of aminoacetonitrile hydrochloride (18, 100 g, 1.08 mol) in dry methanol (100 rnL). After stirring for 2 h at rt the precipitated sodium chloride was filtered off and the filtrate concentrated in vacuo. EtOAc (20 mL) was added and evaporated under reduced pressure to remove all traces of methanol. The oily residue was dissolved in dry EtOAc (100 mL) and anhydrous sodium sulfate added. After cooling, the precipitate was filtered off. The solution of crude aminoacetonitrile was used without further purification. This solution was added drop-wise during a period of 1 h to a vigorously stirred, ice-cooled solution of carbon disulphide (100 mL, 1.66 mol) in dry EtOAc (100 mL) under an N2 atmosphere. Continued mechanical stirring and water-free conditions were essential. The mixture was stirred at 0 °C for 1 h. The resultant precipitate was filtered off, washed with EtaO and dried, giving the product 50 as yellow crystals (99 g, 75 % on amount of sodium), m.p. 131 °C dec. IR (KBr) v max 1630, 1500 cm. ... 

Electrolysis of salts of fatty acids gives free radicals which are capable of reacting with added substrates. For instance, when water-free potassium acetate is electrolyzed in the presence of polymerizing substances (e.g., styrene) methyl groups are incorporated as end groups into the polymer. Goldschmidt et ai. analyzed the products formed in the electrolysis of potassium propionate in propionic acid and showed that they could be accounted for by the following reaction sequence ... 

The products obtained from the electrolysis of water-free fatty acids in pyridine are similar, although the total yields of alkylated products are considerably lower (Table V), presumably because here the radicals are formed in a high concentration on the anode... 

After this reaction-time, the evolution of hydrogen is ceased. Then there are added successively 60 parts dimethylformamide and 8 parts of p-chlorobenzylchloride and stirring and refluxing is continued for another two hours. The tetrahydrofuran is removed at atmospheric pressure. The dimethylformamide solution is poured onto water. The product, 1-[2,4-dichloro-/3-(p-chlorobenzyloxy)phenethyl] imidazole, is extracted with benzene. The extract is washed with water, dried, filtered and evaporated in vacuo. From the residual oily free base, the nitrate salt is prepared in the usual manner in 2-propanol by treatment with concentrated nitric acid, yielding, after recrystallization of the crude solid salt from a mixture of 2-propanol, methanol and diisopropylether, 1-[2,4-dichloro-/3-(p-chlorobenzyl-oxylphenethyl] imidazole nitrate MP 162°C. 

It is instructive to compare, insofar as possible, the gaseous products of PETN decompn and expln. This is done on a water-free basis in Table I . Note the absence of oxides of nitrogen in the expln products and the increase in C02 from decompn to expln... 

Forty-seven grams (0.5 mol) of phenol, 80 mL of 37 wt % aqueous formaldehyde (1.0 mol), and 100 mol of 4 A NaOH were charged to a flask equipped with a reflux condenser and mechanical stirrer. The reaction mixture was stirred at room temperature for 16 h, then heated on a steam bath for 1 h. The mixture was cooled and the pH adjusted to 7.0. The aqueous layer was decanted from the viscous brown liquid product, the wet organic phase was taken up in 500 mL of acetone and dried over anhydrous MgSCL, then over molecular sieves. The dried acetone product solution was filtered and evaporated to yield a water-free light brown syrup. 

Usually in evaporation the thick liquor is the valuable product and the vapour is condensed and discarded. There are, however, specific situations where the opposite is true. In this context, mention may be made of the fact that mineral-containing water is often evaporated to yield a solid-free product for boiler feed, for special process requirements, or for human consumption. This technique is often called water distillation, but technically it is evaporation. 

Subsequently, Bos and Dahmen used in m-cresol65 (e = 12.29 at 25° C) a potentiometric titration method combined with conductometry. Essential precautions were the preparation of water-free m-cresol (<0.01% of water), the use of a genuine Bronsted base B, e.g., tetramethylguanidine (TMG), and the application of a glass electrode combined with an Ag-AgCl reference electrode filled with a saturated solution of Me4NCl in m-cresol. The ion product of the self-dissociation of m-cresol, Ks, was determined from the part beyond the equivalence point of the potentiometric titration curve of HBr with TMG comparison with titration curves calculated with various Ka values showed the best fit for Ks = 2 10 19... 

Hot water injection via injection wells heats the soil and groundwater and enhances contaminant release. Hot water injection also displaces fluids (including LNAPL and DNAPL free product) and decreases contaminant viscosity in the subsurface to accelerate remediation through enhanced recovery. 

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