Calcium chloride, basic

The industrial process for preparing the reagent usually permits a little hydrolysis to occur, and the product may contain a little free calcium hydroxide or basic chloride. It cannot therefore be employed for drying acids or acidic liquids. Calcium chloride combines with alcohols, phenols, amines, amino-acids, amides, ketones, and some aldehydes and esters, and thus cannot be used with these classes of compounds. 

Coumarin. In a 250 ml. round-bottomed flask, provided with a small reflux condenser and a calcium chloride drying tube at the top, place 2 1 g, of salicylaldehyde, 2 0 ml. of anhydrous triethylamine and 5 0 ml. of acetic anhydride, and reflux the mixture gently for 12 hours. Steam distil the mixture from the reaction flask and discard the distillate. Render the residue in the flask basic to litmus with solid sodium bicarbonate, cool, filter the precipitated crude coumarin at the pump and wash it with a little cold water. Acidify the filtrate to Congo red with... 

Alternatively, use the following procedure in which triethylamine replaces potassium acetate as the basic catalyst. Place 2 1 g. (2-0 ml.) of purified benzaldehyde, 2 0 ml. of anhydrous triethylamine and 5 0 ml. of A.R. acetic anhydride in a 200 ml. round-bottomed flask, equipped with a short reflux condenser and a calcium chloride drying tube. Boil the solution gently for 24 hours—heating may be interrupted. Incorporate a steam distillation apparatus in the flask and steam distil until the distillate is no longer cloudy (about 100 ml.) and then collect a further 50 ml. of the distillate di ard the steam distillate. Transfer the residue in the flask to a 400 ml. beaker, add water until the vplume is about 200 ml., then 0 2 g. of decolourising carbon, and boil for a few minutes. Filter the hot solution, and acidify the hot filtrate with 1 1 hydrochlorioiaoid... 

Food. Food-grade calcium chloride is used in cheese making to aid in rennet coagulation and to replace calcium lost in pasteurization. In the canning iadustry it is used to firm the skin of fmit such as tomatoes, cucumbers, and jalapenos. It acts as a control in many flocculation, coagulation systems (37). Food-grade calcium chloride is used in the brewing iadustry both to control the mineral salt characteristics of the water and as a basic component of certain beers (see Beer). 

Ethylene oxide has been produced commercially by two basic routes the ethylene chlorohydrin and direct oxidation processes. The chlorohydrin process was first iatroduced dufing World War I ia Germany by Badische Anilin-und Soda-Eabfik (BASE) and others (95). The process iavolves the reaction of ethylene with hypochlorous acid followed by dehydrochlofination of the resulting chlorohydrin with lime to produce ethylene oxide and calcium chloride. Union Carbide Corp. was the first to commercialize this process ia the United States ia 1925. The chlorohydrin process is not economically competitive, and was quickly replaced by the direct oxidation process as the dominant technology. At the present time, all the ethylene oxide production ia the world is achieved by the direct oxidation process. 

The polymerization of aromatic diamines with acid chlorides in solution works well.7 914 35 The basicity of the aromatic diamine is low and acid binding can be achieved with several compounds and even solvents such as TV-methylpyrrolidonc (NMP) and dimethylacetamide (DMAc). The all-para aromatic amide poly(p-phenyleneterephthalamide) can be synthesized in DM Ac.7,9,14 To prevent precipitation of the polymer, a salt such as calcium chloride or lithium chloride can be added. It is also possible to react the acid chloride with a silylated diamine ... 

A mixture of 45.6 g. (0.2 mole) of benzilic acid (Note 1) in 700 ml. of anhydrous thiophene-free benzene, contained in a 2-1. three-necked flask fitted with a reflux condenser (attached to a calcium chloride drying tube) and a motor-driven sealed stirrer, is cooled in an ice bath until a crystalline mass results. To the stirred mixture is added, in one portion, 80 g. (0.6 mole) of anhydrous aluminum chloride. The stirred mixture is heated until refluxing begins and is maintained at this temperature for 3 hours. During this period much hydrogen chloride is evolved, and the initially yellow solution soon becomes deep red. The solution is cooled and decomposed by the cautious addition of small pieces of ice, and then 400 ml. of water is added cautiously, followed by 200 ml. of concentrated hydrochloric acid. The benzene is removed by steam distillation, and the product is separated by filtration from the hot mixture. The lumps of product are crushed and extracted with 400 ml. of boiling 10% sodium carbonate solution. The mixture is filtered, and the extraction is repeated on the undissolved residue with an additional 200 ml. of hot 10% sodium carbonate solution. The basic filtrates are... 

Ammonia-soda Also called the Solvay process. A process for making sodium carbonate. The basic process was invented and partially developed in the first half of the 19th century by several workers, but the key invention was made by E. Solvay in Belgium in 1861. The first plant was built at Couillet, Belgium, in 1864 and thereafter the process became accepted worldwide, displacing the Leblanc process. The raw materials are limestone and salt calcium chloride is a waste product. The overall reaction is ... 

Saniter A modification of the Basic Open Hearth process for reducing the sulfur content of the steel product by adding relatively large quantities of limestone and calcium chloride. Invented by E. H. Saniter at the Wigan Coal Iron Company in England in 1892, and used there and in Germany for approximately 20 years until superseded by the use of calcium fluoride as a flux. 

The calcium lake of 1,2-dihydroxyanthraquinone is marketed as Pigment Red 83, 58000 1. It is produced commercially by treating a slightly basic alizarin solution with aqueous calcium chloride. 

Anhydrous sodium sulphate, even when freshly ignited before use, is much less active than calcium chloride. It is used when a substitute for calcium chloride is indicated for the reasons given above. For solutions of basic substances ignited potassium carbonate, solid potassium hydroxide, and barium oxide are much used as drying agents. 

Since the calcium chloride contains basic constituents the filling must be saturated with carbon dioxide before the absorption tube is used. For this purpose connect the side tube which leads to the water trap to the Kipp apparatus, interposing a drying tube, pass a strong current of carbon dioxide for 10 minutes, close the outlet, and allow to stand for half an hour, maintaining the pressure of the Kipp. After 200 c.c. of dry air have been drawn through the tube by means of the aspirator, the tube is ready for use. 

The equations that represent the reactions with water support the prediction that NH4NO3 dissolves to form an acidic solution and Na3P04 dissolves to form a basic solution. Calcium chloride is the salt of a strong base-strong acid, so neither ion reacts with water and the solution is neutral. Both ions in ammonium hydrogen carbonate react with water. Because Kt, for HCOs" is greater than for NH4, the salt dissolves to form a weakly basic solution. 

Less basic arsenates may be obtained by precipitation with calcium chloride or nitrate.4... 

Optional Resuspend the pellet in 50 ml of 20 mM HEPES buffer, pH 6.9/2 mM calcium chloride. Incubate with 200 U porcine pancreatic a-amylase at 40°C for 1 hr with stirring. Filter on 1 l- im mesh in a Buchner funnel. Wash twice with 50 ml HEPES/calcium chloride buffer and combine the fdtrates. Dialyze against distilled water as above (step 3) and freeze dry and weigh as described in Basic Protocol 2, steps 14 to 16. 

Granular calcium chloride to absorb water, alcohols, some basic substances. 

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