Sodium commercial preparation

Commercial preparation of sodium perborate tetrahydrate is by reaction of a sodium metaborate solution, from sodium hydroxide and borax pentahydrate, and hydrogen peroxide followed by crystallization of tetrahydrate (95). The tnhydrate and monohydrate can be formed by reversible dehydration of the tetrahydrate. 

Sodium perborate monohydrate, NaBO H2O or Na2B2(02)2(0H)4, 16.0 wt % active oxygen, is commercially prepared by dehydration of the tetrahydrate. The monohydrate has the same peroxyborate anion (7), as the higher hydrates and is the anhydrous sodium salt of this anion. Further dehydration results in decomposition of the peroxyborate. 

Recently, Robach et al. ( ) investigated the effects of various concentrations of sodium nitrite and potassium sorbate on N-nitrosamine formation in commercially prepared bacon. 

Sato, M. et al.. Effect of sodium copper chlorophyUin on lipid peroxidation. IX. On the antioxidative components in commercial preparations of sodium copper chlorophyUin, Chem. Pharm. Bull, 34, 2428, 1986. 

Purity levels of commercial preparations have also been estimated based on their Cu contents and compared with the theoretical values expected for fuUy coppered chlorophyllin based on the two major compounds Cu(ll) chlorin e4 (disodium salt) and Cu(ll) chlorin e6 (trisodium salt). The expected theoretical content of copper in a pure Cu chlorophyllin complex is 9.2%, which has never been found in commercial preparations. The sodium copper chlorophyllin from Sigma-Aldrich (St. Louis, MO) has a 4.5% copper content, specified by the manufacturer with respect... 

Dialyze the phycobiliprotein into 50mM sodium borate, 0.3M NaCl, pH 8.5 (Note Commercial preparations of these proteins come as an ammonium sulfate suspension). 

Traditionally, glucagon preparations utilized therapeutically are chromatographically purified from bovine or porcine pancreatic tissue. (The structure of bovine, porcine and human glucagon is identical, thus eliminating the possibility of direct immunological complications). Such commercial preparations are generally formulated with lactose and sodium chloride and sold in freeze-dried form. Glucagon, 0.5-1.0 units (approximately 0.5-1.0 mg freeze-dried hormone), is administered to the patient by s.c. or i.m. injection. 

The synthetic importance of non-nucleophilic strong bases such as lithium diisopro-pylamide (LDA) is well known but its synthesis involves the use of a transient butyl lithium species. In order to shorten the preparation and make it economically valuable for larger scale experiments an alternate method of synthesis has been developed which also involves a reaction cascade (Scheme 3.14) [92]. The direct reaction of lithium with diisopropylamine does not occur, even with sonication. An electron transfer agent is necessary, and one of the best in this case is isoprene. Styrene is used in the commercial preparation of LDA, but it is inconvenient in that it is transformed to ethylbenzene which is not easily removed. It can also lead to undesired reactions in the presence of some substrates. The advantages of isoprene are essentially that it is a lighter compound (R.M.M. = 68 instead of 104 for styrene) and it is transformed to the less reactive 2-methylbutene, an easily eliminated volatile compound. In the absence of ultrasound, attempts to use this electron carrier proved to be unsatisfactory. In this preparation lithium containing 2 % sodium is necessary, as pure lithium reacts much more slowly. 

In some small-scale preparations of this type in the checkers laboratory, commercial household bleach (Chlorox , 5.25% NaOCl) has been used and the course of the reaction has been followed by thin layer chromatography. The yields appear to be somewhat lower than those obtained with sodium hypochlorite prepared as described above. The obvious attractive alternative, preparation of potassium hypochlorite as described elsewhere in this series, apparently has not been tried. 

The physical and chemical properties of elemental thorium and a few representative water soluble and insoluble thorium compounds are presented in Table 3-2. Water soluble thorium compounds include the chloride, fluoride, nitrate, and sulfate salts (Weast 1983). These compounds dissolve fairly readily in water. Soluble thorium compounds, as a class, have greater bioavailability than the insoluble thorium compounds. Water insoluble thorium compounds include the dioxide, carbonate, hydroxide, oxalate, and phosphate salts. Thorium carbonate is soluble in concentrated sodium carbonate (Weast 1983). Thorium metal and several of its compounds are commercially available. No general specifications for commercially prepared thorium metal or compounds have been established. Manufacturers prepare thorium products according to contractual specifications (Hedrick 1985). 

Commercial (Matheson Co., Inc.) sodium methoxide is most convenient. The reaction can be run using sodium methoxide prepared from sodium and methanol, but this procedure is more tedious since it requires the removal of a considerable amount of methanol. 

Bases are characterized by their bitter taste and slippery feel. Interestingly, bases themselves are not slippery. Rather, they cause skin oils to transform into slippery solutions of soap. Most commercial preparations for unclogging drains are composed of sodium hydroxide, NaOH (also known as lye), which is extremely basic and hazardous when concentrated. Bases are also heavily used in industry. Each year in the United States about 25 billion pounds of sodium hydroxide is manufactured for use in the production of various chemicals and in the pulp and paper industry. Solutions containing bases are often called alkaline, a term derived from the Arabic word for ashes (al-qali), a term we met in Section... 

Colloidal saccharated iron is sometimes used in place of ferric hydroxide as an antidote in arsenical poisoning, but its adsorptive capacity depends on the alkalinity of the medium.4 Thus a commercial preparation containing 0-75 per cent, of sodium hydroxide was found to adsorb 12-57 per cent, of arsenious oxide (reckoned on the amount of iron present) addition of alkali increased the adsorption until, with 1-28 per cent, of sodium hydroxide present, there was a maximum adsorption of 27 per cent. The addition of acid correspondingly diminished the adsorption. A gel of ferric magnesium hydroxide, if prepared without boiling, also adsorbs arsenic from sodium arsenite solutions.5... 

Penicillins have several properties that are characteristic of /i-lactam antibiotics. They are obtained in relatively pure form as off-white, tan, or yellow freeze-dried or spray-dried solids that are usually amorphous. Alternatively they are sometimes obtained as crystalline solids, often as hydrates. Penicillins do not usually have sharp melting points, but decompose upon heating to elevated temperatures. Most natural members have a free carboxyl group and commercial preparations are generally either supplied as salts, most frequently as sodium salts, or in zwitterionic form as hydrates, e.g.. amoxicillin trihydrate. The acid strength of the carboxyl group in aqueous solution varies from pAT = 2.73 for oxacillin to p= 3.06 for carbenicillin. 

Dialyze the phycobiliprotein into 50 mM sodium borate, 0.3 M NaCl, pH 8.5 (note commercial preparations of these proteins come as an ammonium sulfate suspension). After dialysis, adjust the protein solution to a concentration of 1 mg/ml. Higher protein concentrations may be used, but the amount of cross-linking reagent added to each milliliter of the reaction should be proportionally scaled up, as well. Protect the protein solution from undue exposure to light. 

Pour 300 mL 0.1M Sodium acetate buffer solution (pH 4.7) into the vessel and start the stirrer and add 2.5 g of cellulase. (Typical FPU of commercially prepared enzyme is about 100 FPU/g.)... 

While attempting silver recovery from spent developer, a commercial preparation, described as sodium chlorite, was added to the developer, causing violent reaction and spraying the experimenter. There is a suggestion that ammonia was present, and sodium hydroxide, despite which it is claimed that hydrochloric acid was part of the gas release. Poor mixing was involved. Developers being reducants, no involvement of the other destabilising materials (silver, ammonia) need be assumed. 

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