Carbon dioxide basic solutions

Ethylene Oxide Recovery. An economic recovery scheme for a gas stream that contains less than 3 mol % ethylene oxide (EO) must be designed. It is necessary to achieve nearly complete removal siace any ethylene oxide recycled to the reactor would be combusted or poison the carbon dioxide removal solution. Commercial designs use a water absorber foUowed by vacuum or low pressure stripping of EO to minimize oxide hydrolysis. Several patents have proposed improvements to the basic recovery scheme (176—189). Other references describe how to improve the scmbbiag efficiency of water or propose alternative solvents (180,181). 

Carbonates. Basic zirconium carbonate [37356-18-6] is produced in a two-step process in which zirconium is precipitated as a basic sulfate from an oxychloride solution. The carbonate is formed by an exchange reaction between a water slurry of basic zirconium sulfate and sodium carbonate or ammonium carbonate at 80°C (203). The particulate product is easily filtered. Freshly precipitated zirconium hydroxide, dispersed in water under carbon dioxide in a pressure vessel at ca 200—300 kPa (2—3 atm), absorbs carbon dioxide to form the basic zirconium carbonate (204). Washed free of other anions, it can be dissolved in organic acids such as lactic, acetic, citric, oxaUc, and tartaric to form zirconium oxy salts of these acids. 

Basic zirconium carbonate reacts with sodium or ammonium carbonate solutions to give water-soluble double carbonates. The ammonium double carbonate is nominally NH4[Zr20(0H)2(C02)3]. These solutions are stable at room temperature, but upon heating they lose carbon dioxide and hydrous zirconia precipitates. 

Heating the ammonium beryUium carbonate solution to 95°C causes nearly quantitative precipitation of beryUium basic carbonate [66104-24-3], Be(OH)2 2BeC02. Evolved carbon dioxide and ammonia are recovered for recycle as the strip solution. Continued heating of the beryUium basic carbonate slurry to 165°C Hberates the remaining carbon dioxide and the resulting beryUium hydroxide [13327-32-7] intermediate is recovered by filtration. The hydroxide is the basic raw material for processing into beryUium metal, copper—beryUium and other aUoys, and beryUia [1304-56-9] for ceramic products. Approximately 90% of the beryUium content of bertrandite is recovered by this process. 

The diazirines have no basic character, they are not attacked even by strong mineral acids. 3,3-Pentamethylenediazirine (68) could be recovered almost unchanged after the action of methanolic ZN hydrochloric acid for 1 hr. Strong alkalies are also without effect diazirine (67) is unchanged by passing through concentrated sodium hydroxide solution after preparation to eliminate carbon dioxide which is formed simultaneously. ... 

Strong basic solutions are effective solvents for acid gases. However, these solutions are not normally used for treating large volumes of natural gas because the acid gases form stable salts, which are not easily regenerated. For example, carbon dioxide and hydrogen sulfide react with aqueous sodium hydroxide to yield sodium carbonate and sodium sulfide, respectively. 

Carbon dioxide produces a solution of carbonic acid (as in boiler condensate, see Section 53.3.2). Carbon steel is often employed but corrosion rates of up to 1 mm/yr can be encountered. Coatings and non-metallic materials may be employed up to their temperature limits (Section 53.5.6). Basic austenitic stainless steels (type 534) are suitable up to their scaling temperatures. 

It has been found that red lead, litharge and certain grades of metallic lead powder render water alkaline and inhibitive this observation has been confirmed by Pryor . The effect is probably due to a lead compound, e.g. lead hydroxide, in solution. Since, however, atmospheric carbon dioxide converts these lead compounds into insoluble basic lead carbonate, thereby removing the inhibitive materials from solution, these pigments may have only limited inhibitive properties in the absence of soap formation. 

Thus, solutions of carbonates are found to be basic. Aqueous solutions of carbon dioxide are, on the other hand, acidic. The reactions in this equilibrium are... 

Details for the preparation of the solutions referred to in the table are as follows (note that concentrations are expressed in molalities) all reagents must be of the highest purity. Freshly distilled water protected from carbon dioxide during cooling, having a pH of 6.7-7.3, should be used, and is essential for basic standards. De-ionised water is also suitable. Standard buffer solutions may be stored in well-closed Pyrex or polythene bottles. If the formation of mould or sediment is visible the solution must be discarded. 

The green color suggests chromium or copper but the blue solution formed when the mineral is dissolved in sulfuric acid points to copper as the metal (CuS04 is blue). The colorless gas that forms either upon heating or on treatment with acid is carbon dioxide this is proven when the gas is bubbled into limewater (the cloudiness in the solution is due to CaCO. formation). C02 is formed when carbonates are either heated or treated with acid. The mineral is most likely basic copper(ll) carbonate (Cu2C03(0H)2). 

The reduction of carbon dioxide is another of the basic electrochemical reactions that has been studied at modified electrodes. The reduction at Co or Ni phthalocyanine in acidic solution yields formic acid or carbon monoxide A very high selectiv-... 

Sodium carbonate is a white, powdery solid moderately soluble in water to give a basic solution. It reacts with acids to produce a sodium salt and carbon dioxide. 

C19-0050. What are the half-reactions for these redox processes (a) Aqueous hydrogen peroxide acts on Co, and the products are hydroxide and Co , in basic solution, (b) Methane reacts with oxygen gas and produces water and carbon dioxide, (c) To recharge a lead storage battery, lead(II) sulfate is converted to lead metal and to lead(IV) oxide, (d) Zinc metal dissolves in aqueous hydrochloric acid to give ions and hydrogen gas. 

When calcium carbonate goes into solution, it releases basic carbonate ions (COf ), which react with hydrogen ions to form carbon dioxide (which will normally remain in solution at deep-well-injection pressures) and water. Removal of hydrogen ions raises the pH of the solution. However, aqueous carbon dioxide serves to buffer the solution (i.e., re-forms carbonic acid in reaction with water to add H+ ions to solution). Consequently, the buffering capacity of the solution must be exceeded before complete neutralization will take place. Nitric acid can react with certain alcohols and ketones under increased pressure to increase the pH of the solution, and this reaction was proposed by Goolsby41 to explain the lower-than-expected level of calcium ions in backflowed waste at the Monsanto waste injection facility in Florida. 

During neutralisation of the formic acid present in formaldehyde solution by shaking with the basic carbonate in a screw-capped bottle, the latter burst owing to pressure of liberated carbon dioxide. Periodical release of pressure should avoid this. 

Whether for a class demonstration, a practical joke, or perhaps a clandestine activity, disappearing ink is a fascinating substance. What is the secret to its action One formulation of disappearing ink contains a common acid-base indicator, that is, a substance that by its color shows the acid or basic nature of a solution. One acid-base indicator that shifts from a colorless hue under acidic conditions to a deep blue color in alkaline solutions is thymolphthalein. If the indicator starts off in a basic solution, perhaps containing sodium hydroxide, the typical blue color of an ink is perceived. How does the ink color disappear This behavior is dependent upon the contact of the ink with air. Over time, carbon dioxide in the air combines with the sodium hydroxide in the ink solution to form a less basic substance, sodium carbonate. The carbon dioxide also combines with water in the ink to form carbonic acid. The indicator solution responds to the production of acid and returns to its colorless acid form. A white residue (sodium carbonate) remains as the ink dries. 

Disappearing ink can be prepared by first dissolving solid thymolphthalein in ethanol, adding water, and then adjusting the pH with sodium hydroxide solution J2 The deep blue color of the basic form of the indicator is readily apparent. Applying the ink to paper increases its exposure to carbon dioxide in air. Two chemical... 

The submitters used 55 cc. of hydrochloric acid at this point the checkers stated that this amount was insufficient to neutralize the mixture. The purpose of acidification at this point is not to liberate the cyclobutanedicarboxylic acid, but merely to remove carbonates and excess potassium hydroxide. After the carbon dioxide has been expelled, the solution is made alkaline with ammonia hence a great excess of hydrochloric acid should be avoided. The submitters used only enough hydrochloric acid to make the solution acid to litmus. After the solution has been made basic with ammonia, barium chloride solution is added until there is no further precipitation of barium malonate. 

To a flame-dried, three-neck, 1-1 flask were added, in order, p-xylene (107 g, 1.0 mol), phosphorus trichloride (412 g, 3.0 mol), and anhydrous aluminum chloride (160 g, 1.2 mol). The reaction mixture was slowly heated to reflux with stirring. After 2.5 h at reflux, the reaction was allowed to cool to room temperature and the volatile components distilled at reduced pressure. The residual oil was slowly added to cold water (1 1) with stirring, and a white solid formed. The solid was removed by filtration, washed with water, and air dried. The solid was suspended in water (1 1) to which was added 50% sodium hydroxide solution (90 ml) to cause dissolution. The solution was saturated with carbon dioxide and filtered through Celite . The basic solution was washed with methylene chloride (200 ml) and acidified with concentrated hydrochloric acid (200 ml). The white solid that separated was isolated by extraction with methylene chloride (3 x 250 ml). The extracts were dried over magnesium sulfate, filtered, and evaporated under reduced pressure to give the pure 2,5-dimethylbenzenephosphinic acid (99 g, 60%) as an oil, which slowly crystallized to a solid of mp 77-79°C. 

Thenard A process for making white lead pigment (basic lead carbonate) by boiling litharge (lead monoxide) with lead acetate solution and passing carbon dioxide gas into the suspension. 

Typically, acid soils are titrated with a sodium or calcium hydroxide [NaOH or Ca(OH)2] solution and basic soils with hydrochloric acid (HC1), and pH changes are most commonly followed using a pH meter. Carbonates in basic soils release C02 during treatment with HC1, thus making the titration more difficult. For this reason, carbonates are often determined by other methods. It is important to keep in mind that basic solutions react with carbon dioxide in air and form insoluble carbonates. This means that either the basic titrant is standardized each day before use or the solution is protected from exposure to carbon dioxide in air. Specific descriptions of titrant preparation, primary standards, and the use of indicators and pH meters in titrations can be found in Harris [1] and in Skoog et al. [2],... 

In this experiment the neutralizing power of various antacids will be determined. Antacids contain basic compounds that will neutralize stomach acid (stomach acid is HC1). The amount of base in the antacid tablets will be determined by an acid-base titration. It is a back titration method. This method is used because most antacids produce carbon dioxide gas, which can interfere with the titration. By initially adding an excess of acid, one can drive off the C02 by boiling the solution before titrating the excess acid. There are many brands of commercial antacids with various ingredients. A few of the common ones are listed below ... 

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