Water condenser

The gaseous reactor product is cooled first by boiler feedwater before entering a cooling water condenser. The cooling duty provided by the boiler... 

Hydrogen chloride released dissolves in water during condensation in the crude oil distillation column overhead or in the condenser, which cause corrosion of materials at these locations. The action of hydrochloric acid is favored and accelerated by the presence of hydrogen sulfide which results in the decomposition of sulfur-containing hydrocarbons this forces the refiner to inject a basic material like ammonia at the point where water condenses in the atmospheric distillation column. 

If produced gas contains water vapour it may have to be dried (dehydrated). Water condensation in the process facilities can lead to hydrate formation and may cause corrosion (pipelines are particularly vulnerable) in the presence of carbon dioxide and hydrogen sulphide. Hydrates are formed by physical bonding between water and the lighter components in natural gas. They can plug pipes and process equipment. Charts such as the one below are available to predict when hydrate formation may become a problem. 

The reports were that water condensed from the vapor phase into 10-100-/im quartz or pyrex capillaries had physical properties distinctly different from those of bulk liquid water. Confirmations came from a variety of laboratories around the world (see the August 1971 issue of Journal of Colloid Interface Science), and it was proposed that a new phase of water had been found many called this water polywater rather than the original Deijaguin term, anomalous water. There were confirming theoretical calculations (see Refs. 121, 122) Eventually, however, it was determined that the micro-amoimts of water that could be isolated from small capillaries was always contaminated by salts and other impurities leached from the walls. The nonexistence of anomalous or poly water as a new, pure phase of water was acknowledged in 1974 by Deijaguin and co-workers [123]. There is a mass of fascinating anecdotal history omitted here for lack of space but told very well by Frank [124]. 

Experimental Determination of Boiling-point. Unless only minute quantities of the liquid are available cj. p. 60), the boiling-point is usually determined by simple distillation. For this purpose, the apparatus shown in Fig. 2 is assembled. A distillation flask A of suitable size is fitted to a water-condenser B, the water supply of which is arranged as show-n. An adaptor C is sometimes fitted in turn to the condenser, so that the distillate... 

A water-condenser can be used for any liquid the boiling-point of which does not exceed 140°. Above this temperature, an air-condenser (i.e., a straight glass tube having no jacket) should be used. If a water-condenser is used above 140°, there is always a risk of the condenser cracking at the point where the hot vapour first meets the water-cooled portion. 

The water-condenser B shown in Fig. 2 represents the simplest and cheapest kind, which because of its limited efficiency should be at least 2 feet long. Fig. 3(A) IV shows a bulb condenser, which, although also cheap, is much more efficient. In Fig. 

Most students will be familiar with simple distillation from their practical inorganic chemistry. Other students should determine the boiling-point of acetone (56°), using a water-bath and water-condenser, or of benzene (81 ), using a sand-bath and water-condenser, and finally of either aniline (184 ) or nitrobenzene (210 ), using for both these liquids a sand-bath and air-condenser. 

The crude material is therefore placed either in a round-bottomed bolt-head flask (Fig. 8) or in a conical flask, the solvent added (again in slight deficiency) and a reflux water-condenser fitted to the flask as shown. The mixture is boiled either on a water-bath or over a gauze, and then more solvent added cautiously down the condenser until a clear solution (apart from insoluble impurities) is again obtained. It is then filtered hot as described above. 

The crude organic material is placed in a porous thimble G (made of tough filter-paper), and the latter placed as shown within the inner tube C. The apparatus is then fitted below to a bolt-head flask H containing the requisite solvent, and above to a reflux water-condenser J. 

Round-bottomed flasks (Fig. 22(A)) of various sizes and having necksof various lengths and widths. They can be closed with stoppers (Fig. 22(B)), or fitted with any of the following units reflux air-condensers (Fig. 22(C)) or water condensers (Fig. 22(D)) distillation heads, of the simple knee-tube type (Fig. 22(E)), or with a vertical joint (Fig. 22(F)) for thermometers, etc., or with... 

Reflux Distillation Unit. The apparatus shown in Fig. 38 is a specially designed distillation-unit that can be used for boiling liquids under reflux, followed by distillation. The unit consists of a vertical water-condenser A, the top of which is fused to the side-arm condenser B. The flask C is attached by a cork to A. This apparatus is particularly suitable for the hydrolysis of esters (p. 99) and anilides (p. 109), on a small scale. For example an ester is heated under reflux with sodium hydroxide solution while water is passed through the vertical condenser water is then run out of the vertical condenser and passed through the inclined condenser. The rate of heating is increased and any volatile product will then distil over. 

A very suitable apparatus for semi-micro steam-distillation, particularly for suspensions that are likely to bump badly, is showm in Fig. 44. This consists of a 50 ml. Kjeldahl flask, clamped at an angle of 45°, and fitted with a long glass tube for the inlet of steam. The Outlet-tube is bent twice, first at 135° and then at 45° as shown, and fitted into a small water-condenser. 

The latter is connected above to a water-condenser and below to a flask which contains a liquid of appropriate boiling-point. The inner tube is connected to a water-pump. A more satisfactory pistol (Fig. 48(B)) consists of a wide glass tube A closed at each end by ground-glass caps. 

Fit a 500 ml. bolt-head flask F with a well-fitting cork which is free from flaws, and which carries a dropping-funnel D and a delivery tube (or knee-tube ) T, the latter being connected to a water-condenser C (Fig. 52). Attach an adaptor A to the lower end of the condenser. (Alternatively, use a ground-glass flask (Fig. 22(a), p. 43) with a distillation-head (Fig. 22(F)) the dropping-funnel can be fitted into the distillation-head, the side-arm of which is connected to a condenser as in Fig. 23(0), p. 45.)... 

Fit a 50 ml. bolt-head flask F (Fig. 53) with a reflux water-condenser C, to the top of which a dropping-funnel D is fixed by means of a cork having a vertical V-shaped groove G cut or filed in the side to... 

To prepare pure acetylene, assemble the apparatus shown in Fig. 57. F is a wide-necked 300 ml. bolt-head flask, to which is fitted a double-surface reflux water-condenser C and the dropping-funnel D. From the top of C, a delivery-tube leads down to the pneumatic trough T, where the gas can be collected in jars in the usual way. (Alternatively, use the apparatus shown in Fig. 23(A),... 

Place 0 5 ml. of acetone, 20 ml. of 10% aqueous potassium iodide solution and 8 ml. of 10% aqueous sodium hydroxide solution in a 50 ml. conical flask, and then add 20 ml. of a freshly prepared molar solution of sodium hypochlorite. Well mix the contents of the flask, when the yellow iodoform will begin to separate almost immediately allow the mixture to stand at room temperature for 10 minutes, and then filter at the pump, wash with cold w ater, and drain thoroughly. Yield of Crude material, 1 4 g. Recrystallise the crude iodoform from methylated spirit. For this purpose, place the crude material in a 50 ml. round-bottomed flask fitted with a reflux water-condenser, add a small quantity of methylated spirit, and heat to boiling on a water-bath then add more methylated spirit cautiously down the condenser until all the iodoform has dissolved. Filter the hot solution through a fluted filter-paper directly into a small beaker or conical flask, and then cool in ice-water. The iodoform rapidly crystallises. Filter at the pump, drain thoroughly and dry. 

The oxime is freely soluble in water and in most organic liquids. Recrystallise the crude dry product from a minimum of 60-80 petrol or (less suitably) cyclohexane for this purpose first determine approximately, by means of a small-scale test-tube experiment, the minimum proportion of the hot solvent required to dissolve the oxime from about 0-5 g. of the crude material. Then place the bulk of the crude product in a small (100 ml.) round-bottomed or conical flask fitted with a reflux water-condenser, add the required amount of the solvent and boil the mixture on a water-bath. Then turn out the gas, and quickly filter the hot mixture through a fluted filter-paper into a conical flask the sodium chloride remains on the filter, whilst the filtrate on cooling in ice-water deposits the acetoxime as colourless crystals. These, when filtered anddried (either by pressing between drying-paper or by placing in an atmospheric desiccator) have m.p. 60 . Acetoxime sublimes rather readily when exposed to the air, and rapidly when warmed or when placed in a vacuum. Hence the necessity for an atmospheric desiccator for drying purposes. 

After about 20 minutes, when the liquid should be dry, filter it through a small fluted filter-paper into a 100 ml. distilling-flask attached to a water-condenser. Add some fragments of unglazed porcelain to the ethyl acetate, fit a 100° thermometer to the flask, and place the latter on a cold water-bath, which is then brought to the boil. Some ether is always formed as a by-product with the ethyl acetate, and by these means is carefully distilled off as a... 

Place 5 mi. of ethyl acetate in a 100 ml. round-bottomed flask, and add about 50 ml. of 10% sodium hydroxide solution, together with some fragments of ungiazed porcelain. Fit the flask with a reflux water-condenser, and boil the mixture gently over a wire gauze for 30 minutes. Now disconnect the condenser, and fit it by means of a bent delivery-tube (or knee-tube ) to the flask for direct distillation (Fig. 59, or Fig. 23(0), p. 45). Reheat the liquid, and collect the first 10 ml. of distillate, which will consist of a dilute aqueous solution of ethanol. Confirm the presence of ethanol by the iodoform test Test 3, p. 336). 

Assemble the apparatus shown in Fig. 6o. A is a 500 ml. bolt-head flask connected by a knee-tube B to a water-condenser C, to the lower end of which is fitted the adaptor D. In view of the low boiling-point of the ethyl bromide, it is essential that the various portions of the apparatus are connected together by well-bored, tightly fitting corks. (For this reason, the apparatus shown in Fig. 23(0), p. 45, is preferable.)... 

Fit the flask with a 100° thermometer and a water-condenser, and distil the ethyl iodide carefully from a water-bath, collecting the fraction which distils between 68° and 73°. Yield, about 24 g. 

Add 20 ml. of a mixture of equal volumes of acetic anhydride and glacial acetic acid to 10 ml. (10 3 g.) of aniline contained in a 150 ml. conical flask. Fit a reflux water-condenser to the flask, and boil the mixture gently for 10 minutes. Then pour the hot liquid into 200 ml. of cold water, stirring the latter well... 

Place I g. of acetanilide and 10 ml. of the 70% sulphuric acid in a small flask fitted with a reflux water-condenser, and boil the mixture gently for 15 minutes, when the hot solution will smell perceptibly of... 

Add 5 g. of potassium hydrogen tartrate and 5 g. of antimony trioxide (each being finely powdered) to 30 ml. of water contained in a small flask, and boil the mixture under a reflux water-condenser for 15 minutes. Then filter hot, using a Buchner funnel and flask which have been preheated by the filtration of some boiling distilled water. Pour the clear filtrate into a beaker and allow to cool. Potassium antimonyl tartrate separates as colourless crystals. Filter, drain and dry. Yield, 5 g. The product can be recrystallised from hot water, but this is usually not necessary. 

Place I g. of benzamide and 15 ml. of 10% aqueous sodium hydroxide solution in a 100 ml. conical flask fitted with a reflux water-condenser, and boil the mixture gently for 30 minutes, during which period ammonia is freely evolved. Now cool the solution in ice-water, and add concentrated hydrochloric acid until the mixture is strongly acid. Benzoic acid immediately separates. Allow the mixture to stand in the ice-water for a few minutes, and then filter off the benzoic add at the pump, wash with cold water, and drain. Recrystallise from hot water. The benzoic acid is obtained as colourless crystals, m.p. 121°, almost insoluble in cold water yield, o 8 g. (almost theoretical). Confirm the identity of the benzoic acid by the tests given on p. 347. 

Add I g. of finely powdered mercuric oxide and o-8 g. of benzamide to 10 ml. of ethanol, and boil the mixture under a reflux water condenser for 30 minutes. Now filter the hot solution through a fluted filter-... 

The crude acetonitrile contains as impurity chiefly acetic acid, arising from the action of phosphoric acid on the acetamide. Therefore add to the nitrile about half its volume of water, and then add powdered dry potassium carbonate until the well-shaken mixture is saturated. The potassium carbonate neutralises any acetic acid present, and at the same time salts out the otherwise water-soluble nitrile as a separate upper layer. Allow to stand for 20 minutes with further occasional shaking. Now decant the mixed liquids into a separating-funnel, run off the lower carbonate layer as completely as possible, and then pour off the acetonitrile into a 25 ml, distilling-flask into which about 3-4 g. of phosphorus pentoxide have been placed immediately before. Fit a thermometer and water-condenser to the flask and distil the acetonitrile slowly, collecting the fraction of b.p. 79-82°. Yield 9 5 g. (12 ml.). 

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