The reaction between an acid and a base that produces salt and water is called a neutralization reaction.
We studied the reactions of acids with metals and metal oxides. These reactions produce a salt of the corresponding metal. Bases also contain metals. It can be assumed that acids will interact with bases to also form salts. Add a solution of hydrochloric acid HCl to a solution of sodium hydroxide NaOH.
The solution remains colorless and transparent, but by touch it can be determined that heat is released. The release of heat indicates that a chemical reaction has occurred between the alkali and acid.
To find out the essence of this reaction, let's do the following experiment. Place a piece of paper colored with purple litmus into the alkali solution. She will, of course, turn blue. Now, from the burette, we will begin to add the acid solution to the alkali solution in small portions until the color of the litmus again changes from blue to violet. If litmus turns from blue to purple, this means that there is no alkali in the solution. There was no more acid in the solution, since in its presence the litmus would have turned red. The solution became neutral. Having evaporated the solution, we obtained a salt - sodium chloride NaCl.
The formation of sodium chloride when sodium hydroxide reacts with hydrochloric acid is expressed by the equation:
NaOH + HCl = NaCl + H 2 O + Q
The essence of this reaction is that sodium and hydrogen atoms exchange places. As a result, the hydrogen atom of the acid combines with the hydroxyl group of the alkali to form a water molecule, and the sodium metal atom combines with the acid residue – Cl, forming a salt molecule. This reaction belongs to the familiar type of exchange reactions.
Do insoluble bases react with acids? Pour blue copper hydroxide into a glass. Let's add water. Copper hydroxide will not dissolve. Now let’s add a solution of nitric acid to it. The copper hydroxide will dissolve and a clear, blue-colored solution of copper nitrate will be obtained. The reaction is expressed by the equation:
Cu(OH) 2 + 2HNO 3 = Cu(NO 3) 2 + 2H 2 O
Bases that are insoluble in water, like alkalis, react with acids to form salts and water.
Using the neutralization reaction, insoluble acids and bases are determined experimentally. Oxide hydrates that react with neutralization with alkalis are classified as acids. Having verified from experience that this oxide hydrate is neutralized by alkalis, we write its formula as an acid formula, writing the chemical sign of hydrogen in first place: HNO3, H2SO4.
Acids do not interact with each other to form salts.
Oxide hydrates that undergo a neutralization reaction with m compounds are classified as bases. Having verified from experience that this oxide hydrate is neutralized by acids, we write its formula in the form Me(OH)n, i.e. we emphasize the presence of hydroxyl groups in it.
Bases do not interact with each other to form salts.
Lesson topic: “The neutralization reaction as an example of an exchange reaction”
Objective of the lesson: form an idea of the neutralization reaction as a special case of an exchange reaction.
Tasks:
Create conditions for the development of ideas about the neutralization reaction as a special case of the exchange reaction;
Expand students' knowledge of the properties of acids and bases;
Continue developing skills in drawing up equations of chemical reactions;
Cultivate observation and attention during the demonstration experiment.
Lesson type : combined
Equipment and reagents : hydrochloric acid, solutions of sodium hydroxide, copper (II) hydroxide, phenolphthalein, test tubes.
Lesson progress
Organizational moment.
Guys, let's continue our journey around the country called Chemistry. In the last lesson, we got acquainted with a city called Foundations and its inhabitants. The main inhabitants of a given city are the foundations. Define the concept of “foundation”. Well, now let's check how you did your homework.
Checking homework.
№ 7, 8.
Survey and further updating of knowledge.
What classes of inorganic substances do you know?
Define the terms “oxides”, “acids”, “salts”.
What substances does water react with?
What substances are formed when water reacts with basic and acidic oxides?
How to prove that acid is formed as a result of the interaction of water with an acid oxide?
What are indicators?
What indicator are we talking about?
The alkali makes me yellow, like in a fever,
I blush from acids, as if from shame.
And I'm looking for saving moisture,
So that Wednesday could not eat me.
(Methyl orange)
It's bad luck for him to fall into acid.
But he will endure it without sighing or crying.
But in alkalis such a blond
What will begin is not life, but pure raspberries.
(Phenolphthalein.)
What other indicators do you know?
Define the terms “acid oxide” and “basic oxide”.
What groups are bases divided into?
What color does phenolphthalein, methyl orange, and litmus turn in an alkali solution?
Learning new material.
You already know that alkalis are soluble bases; when working with them, you must follow special rules of safe behavior, since they have a corrosive effect on our skin. But they can be “neutralized” by adding an acid solution to them - neutralizing them. And the topic of today’s lesson: “The neutralization reaction as an example of an exchange reaction” (write the topic on the board and in a notebook).
The purpose of today's lesson: to form an idea of the neutralization reaction; learn to write equations for neutralization reactions.
Let's remember what types of chemical reactions you already know. Determine the reaction data type
Na 2 O + H 2 O = 2 NaOH
2H 2 O = 2H 2 + O 2
Zn + 2HCl =ZnCl 2 +H 2
Define these types of reactions.
You also already know that if you add phenolphthalein to alkali, the solution will turn crimson in color. But if acid is added to this solution, the color disappears (dem. interactionsNaOHAndHCl). This is a neutralization reaction.
Writing the equation on the board:NaOH + HCl= NaCl +H 2 O
The result is salt and water.
Let's all try to define the neutralization reaction together.
The neutralization reaction does not belong to any of the previously known types of reactions. This is an exchange reaction. General scheme exchange reactions: AB + CD = AD + CB
That is, this is a reaction between complex substances, during which they exchange their components.
Who knows what acid is in our stomach? Why do you think that if you have heartburn, it is recommended, if you don’t have a tablet at hand, to drink a little soda solution?
The fact is that the soda solution also has an alkaline environment and when we drink this solution, a neutralization reaction occurs. A solution of soda neutralizes hydrochloric acid found in our stomach.
Do you think insoluble bases react with acids? (Students' answers). Dem. Cu(OH) interactions 2 And HCl .
Writing the equation on the board:Cu(OH) 2 + 2 HCl = CuCl 2 + 2 H 2 O.
Consolidation
Complete the following reaction equations:
A) KOH+H 2 SO 4 = …;
b)Fe(OH) 2 + HCl =…;
V) Ca(OH) 2 +H 2 SO 4 =…. .
Which starting materials must be taken to obtain the following salts by neutralization reaction:Ca( NO 3 ) 2 ; NaI; BaSO 4.
Substances given:HCl; H 2 SO 4 ; Fe( OH) 3 . Write down equations for all possible neutralization reactions between them.
Physical education minute: The teacher shows the substances, and the students need to determine which class of substances the substance belongs to and perform the following actions: oxide - hands up, salt - stand up, acid - hands to the sides, bases - do nothing.
Generalization
Complete the proposed diagram
Main classes of inorganic substances
CO 2 ; Na 2 O? ? ?
N 2 SO 4 ; HCl NaOH;Ca(OH) 2 CaCl 2; Na 2 SO 4
2.Complete the sentences below:
A group of OH atoms is called…..
The valence of this group is constant and equal to ....
Bases are made up of atoms... and one or more... .
The chemical properties of bases include their effect on .... In this case, the indicators acquire color: litmus - ....; phenolphthalein - ....; methyl orange - ... .
In addition, bases react with... .
This reaction is called reaction...
The products of this reaction are... And …. .
An exchange reaction is a reaction between... substances in which they exchange their ... parts.
The neutralization reaction is a special case of the reaction....
VII Reflection
What new things did you learn in today's lesson? Have we achieved the goals set in the lesson?
Homework: § 33 No. 6, prepare for practical work № 6
Additional information:Did you know that women Ancient Rus' Did you wash your hair with a solution of spruce ash or sunflower ash? The ash solution is soapy to the touch and is called “lye.” Such a solution has an alkaline environment, like the substances we are studying. In Arabic, ash is “al-kali.”
Historical names of the most important alkalis: sodium hydroxide - caustic soda, potassium hydroxide - caustic potassium. Alkalis are used to make glass and soap.
Mystery:
It contains metal and oxygen,
Yes, plus hydrogen.
And such a combination
Called -….. (base)
Leonid Chueshkov
“Ash” is always ahead here,
And what remains behind it?
It stings and burns.
And at first glance it’s simple,
And it’s called - ... (acid)
Leonid Chueshkov
In the protolytic interactions considered so far (ionization of weak electrolytes and hydrolysis of salt ions), the obligatory component was water, the molecules of which, exhibiting the properties of an ampholyte, acted as either a donor or an acceptor of a proton, ensuring the occurrence of these interactions. Now let’s consider the direct interaction of acids and bases with each other, i.e. neutralization reactions.
A neutralization reaction is the protolytic interaction of an acid and a base, resulting in the formation of salt and water.
Depending on the strength of the acid and base involved, the neutralization reaction can be virtually irreversible or reversible to varying degrees.
When any strong acid interacts with any strong base (alkali), due to the fact that these reagents are completely dissociated into ions, the essence of such a reaction, regardless of the nature of the reagents, is expressed by the same molecular ionic equation:
In the process of neutralizing a strong acid with an alkali, the pH of the system changes, corresponding to the neutralization curve shown in Fig. 8.1. The neutralization curve in this case is characterized by a large and sharp jump in pH near the equivalence state (Veq) - The middle of this jump corresponds to the equivalence point, at which [H + ] = [OH-] = = 1 10 -7 mol/l, i.e. pH = 7.
Characteristic features of the reaction of neutralization of a strong acid with an alkali and vice versa are:
Irreversibility;
Exothermicity ( H 0= -57.6 kJ/mol);
Very high speed, since only mobile ions H + and OH- interact;
The pH jump during neutralization is large and sharp;
Equivalence point at pH = 7.
These features of the neutralization reaction between strong acids and bases have ensured its widespread use in analytical practice for the quantitative determination of acids and bases in the objects under study.
The most common case of a neutralization reaction is the interaction of acids and bases that differ in strength. Let's consider the neutralization of a weak acid HA with a strong base (alkali):
Since HA and H20 are weak electrolytes, protolytic equilibrium occurs due to competition for the proton between the strong bases OH- and A- and, therefore, this neutralization reaction will be characterized by the following features:
Reversibility;
The pH jump during neutralization is small and less sharp (Fig. 8.2), and with decreasing acid strength it decreases and smoothes out;
The equivalence point is located at pH > 7, since the hydrolysis reaction of the anion occurs in the system with the formation of OH- anions, the more of which the weaker the acid;
V E KB), when 50% alkali is added and [HA] = [A-], the pH value in the system is numerically equal to the value pK a of this weak acid.
The last position follows from the equation: pH = pK a+lg ([A-]/[NA]), according to which at [A - ] = [HA] pH = pK a(since lg ([A-]/[HA]) = 0). This circumstance allows not only to determine the value pK a weak acid, but also solve the inverse problem: by value pK a determine which weak acid is in the system.
Reactions of neutralization of bases of different strengths with a strong acid (Fig. 8.3) are characterized by features of equilibrium protolytic processes similar to those given above. However, you need to understand and remember that the following features are characteristic of neutralizing weak bases:
- 
the equivalence point is at pH< 7 из-за протекающей параллельно реакции гидролиза по катиону с образованием катионов Н + ;
In a state of semi-neutralization (1/2 V E KB), when 50% acid is added and [B] = [BH + ], the pH value in the system is numerically equal to the pK value (BH +) of the conjugate acid of a given weak base.
Thus, the study of the neutralization reaction makes it possible to determine not only the content of acids and bases in the system, but also the value pK a weak electrolytes, including proteins, as well as their isoelectric points.
As a result, salts and water are formed, for example:
Examples
Application
Neutralization underlies a number of the most important methods of titrimetric analysis.
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See what a “neutralization reaction” is in other dictionaries:
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The neutralization reaction (for example, sulfuric acid) in a reservoir due to calcium bicarbonates proceeds according to the formula Ca(HC03)24-H2304=Ca304+2H20+2C02.[...]
Neutralization with limestone is not always effective, since in the presence of sulfuric acid, gypsum formed on the surface of limestone particles inhibits the further progress of the neutralization reaction. [...]
A neutralization reaction is a chemical reaction between substances that have the properties of an acid and a base, which results in the loss of the characteristic properties of both compounds. The most typical neutralization reaction in aqueous solutions occurs between hydrated hydrogen ions and hydroxide ions contained in strong acids and bases, respectively: H+ + 0H = H20. As a result, the concentration of each of these ions becomes equal to that characteristic of water itself (about 10 7), i.e., the active reaction of the aquatic environment approaches pH = 7. [...]
The reaction between a base and an acid, resulting in salt and water, is a neutralization reaction.[...]
Neutralization by filtration involves passing the waste liquid through a layer of filter material. When a liquid passes through such a filter, the neutralization reaction must be completely completed. Limestone, marble and dolomite are used as filter materials to neutralize acids. This method has a number of advantages: it is simpler and cheaper, and is effective when the concentration of acids in wastewater is uneven.[...]
The neutralization reaction of acids can also be carried out using other reagents such as bases. The consumption of these substances to neutralize 1 g of various acids (stoichiometric) is given in table. 6.[...]
The neutralization reaction and the calculation of the amount of an unknown substance from this reaction are very widely used in agrochemical laboratories. This kind of calculation is possible for all chemical equations, correctly composed.[...]
The neutralization reaction proceeds very quickly, and with further mixing, the entire mass of wastewater acquires the same pH value within a few minutes.[...]
To neutralize waters of the first type, any of the above reagents can be used. When neutralizing waters of the second type, salts not only precipitate, but at high concentrations can be deposited on the surface of the neutralizing material and slow down the reaction. Neutralization of waters of the third type is possible only with alkali solutions.[...]
When neutralizing sulfuric acid with lime or chalk, 98 parts of acid yield 172 parts of gypsum dihydrate Ca3D. 2N20.[...]
The method of neutralization by filtration consists in the fact that acidic wastewater, after preliminary clarification, is passed through a layer of neutralizing material at such a speed that during the time the water comes into contact with the material, the neutralization reaction is completed.[...]
In the reaction chamber, not only the free acid is neutralized, but also the crystallization of calcium salts and the flocculation of metal hydroxides are completed, which leads to the final stabilization of the pH. From this point of view, installing the sensor after the reaction chambers is the most rational. However, it should be borne in mind that the establishment of a stable control system using industrial devices is extremely complicated if the transport delay time exceeds 10-15 minutes. Based on these considerations, it is often necessary to abandon the location of the sensor of the control device after the reaction chamber, designed for more than ten minutes of water exposure. In this case, the sensor of the control device can be installed at the outlet of the mixer or somewhere along the path of water movement between the mixer and the reaction chamber (or settling tank) - where the neutralization reaction has taken place most completely. Under operating conditions, such a place can be easily found by testing samples taken sequentially along the path of movement of water mixed with the reagent. Where the pH value of the sample taken remains unchanged after thorough mixing, the value of the regulating parameter is measured.[...]
Reagents for neutralizing acidic wastewater are selected depending on the type of acids and their concentration. In addition, it is taken into account whether a precipitate is formed during the neutralization reaction. To neutralize mineral acids, any alkaline reagent is used, but most often the following: lime in the form of fluff or milk of lime, as well as calcium or magnesium carbonates in the form of a suspension.[...]
The method is based on the reaction of neutralization of salicylic acid with alkali. The end of the reaction is recorded by a potentiometer.[...]
The choice of reagent for neutralizing acidic wastewater depends on the type of acids and their concentration, as well as on the solubility of the salts formed as a result chemical reaction. To neutralize mineral acids, any alkaline reagent is used, but most often lime in the form of fluff or milk of lime and calcium or magnesium carbonates in the form of a suspension. These reagents are relatively cheap and widely available, but have a number of disadvantages: in this case, it is necessary to install averagers before the neutralization installation, it is difficult to regulate the dose of the reagent based on the pH of neutralized water, and the reagent management is complicated. The rate of reaction between the acid solution and the solid particles of the suspension is relatively low and depends on the particle size and the solubility of the compound formed as a result of the neutralization reaction. Therefore, the final active reaction in the liquid phase is not established immediately, but after some time (10-15 minutes). The above applies to wastewater containing strong acids (H2504, H2503), the calcium salts of which are sparingly soluble in water. [...]
To control the neutralization reaction, you need to know how much acid or alkali should be added to the solution to obtain the required pH value. To solve this problem, a method of empirical estimation of stoichiometric coefficients can be used, which is carried out using titration.[...]
As we can see, the famous annihilation reaction e+ +e = 2b can be considered, logically and reasonably, as a neutralization reaction - a conclusion, in my opinion, is not only interesting, but also elegant.[...]
To completely complete the reaction of neutralization and flocculation of the suspension, wastewater flowing through the tank is mixed compressed air(for the purpose of oxidizing Fe2+ to Fe3+) or mechanically. An appropriate amount of flocculating agents is added to the flocculator (or neutralizing tank), which promotes the formation of dense agglomerates from an easily sedimentable suspension. The flocculator should be three to six times larger than the neutralizer tank.[...]
From the neutralization reactions presented above, it can be calculated that under stoichiometric conditions, the consumption of CaO per 1 g of the corresponding compounds will be as follows: H2SO4 - 0.56 g; FeS04 - 0.37 g; NS1-0.77 g; FeCl2 - 0.44 g; HN03 - 0.44 g; Fe(N03h - 0.31 g; H3PO4 -0.86 g [...]
It is important to emphasize that the neutralization reactions of OH- formed during the dissolution of carbonates and silicates involve not only carbonic acid, but also organic acids (especially fulvic and humic), which are agents of intense decomposition of rocks. Strong dissociation of many organic acids leads to an increase in H concentrations in water. The dissociation constants of such common compounds in nature as fulvic and humic acids approach u-10-3-“10"5. This means that they can reduce the pH of real groundwater to 3 or less. In connection with this, such organic acids intensively decompose silicates with the destruction of their crystal lattice. The lower the mineralization of groundwater and the more acidic it is, the greater the degree of such decomposition.[...]
Example 6. Calculate the duration of the reaction for neutralizing acidic solutions with a lime suspension if the reaction is carried out in a periodic ideal displacement reactor (RIS-P).[...]
The simplest purification system based on a neutralization reaction can be imagined in the form of crushed limestone, onto which an acid solution was poured, and the sediment was collected in a settling tank.[...]
Analysis of concentration fluctuations and the mechanism of neutralization reactions of acidic iron-containing wastewater served as the basis for choosing parameters for regulating this process. It became obvious that regulating the supply of neutralizing reagent based on pH alone is not enough. A second parameter is needed that could respond to the presence of iron sulfate in water and influence the supply of the reagent in accordance with its current concentrations. [...]
In order to ensure1 completeness and acceleration of the reaction of neutralization and precipitation of heavy metal salts in the reaction chambers, wastewater is continuously mixed with propeller or paddle mixers with a vertical axis of rotation. The rotation speed of the mixer is taken to be at least 40 min-1; at a rotation speed of 150 min-1, the duration of contact of wastewater containing heavy metal ions can be reduced to 15 minutes [...]
Processes of chemical capture of impurities are used to neutralize the most large-scale environmental pollutants: nitrogen oxides, sulfur dioxide, hydrogen sulfide, halogens, etc. Since the specific reactions of neutralization of each of these substances are individual, it is more convenient to consider the available purification methods in relation to the listed main gas pollutants.[ .. .]
As we can see, everything turns out very strictly and logically: in both cases, the neutralization reaction is reduced to the combination of lyonium and lyate ions; in both reactions, a salt, potassium chloride, is obtained as a neutralization product.[...]
When alkalizing oil, you can not take into account the consumption of reagents for hydrogen sulfide, since hydrogen chloride reacts first as a stronger acid. [...]
The reactor can be considered as an isolated system (heat loss in environment insignificant), and the neutralization processes occurring in it are spontaneous and irreversible. About 2.5 Mcal/h will be released in the reactor as a result of neutralization reactions, which obviously corresponds to an increase in the free energy of active waste substances during their formation at industrial enterprises.[ ...]
A favorite criticism of the solvosystem theory was that it cannot describe acid-base reactions not in “its own solvent.” [...]
To prevent corrosion of sewer lines treatment facilities, disturbances of biochemical processes in biological oxidizers and water sources, as well as precipitation from wastewater of all salts of heavy metals, acidic and alkaline waters are neutralized. The most typical neutralization reaction is the reaction between hydrogen and hydroxyl ions, resulting in the formation of slightly dissociated water; H++Obg = H20. As a result of the reaction, the concentration of each of these ions becomes the same (about 107), i.e. the active reaction of the aquatic environment approaches pH = 7.[...]
The main reason for the formation of sediments is the interaction of wastewater with reservoir water, when the solution environment changes in the direction of approaching the pH of reservoir water, i.e., to equilibrium reservoir conditions, usually close to neutral. Neutralization is accompanied by hydrolysis of waste water components. In some cases, due to contact with acidic and alkaline environments, partial dissolution of the rocks composing the formation may occur, followed by practically uncontrolled secondary formation of sediments as a result of neutralization reactions. In addition, one of the reasons for the formation of precipitation may be the introduction of wastewater components reacting with components of formation water, resulting in the formation of sediments even without changing the solution environment.[...]
The electrodes used for titration of acids and bases are indicators of the concentration of hydrogen ions. We will consider two types of electrodes: antimony and glass, which, in our opinion, can be successfully used in sanitary-chemical analysis for the neutralization reaction and determination of the pH of solutions.[...]
It is impossible, however, to agree that all the nitric acid released by nitrifying bacteria during the oxidation of nitrous acid in the soil will be neutralized only through the decomposition of phosphate rock. Even in non-carbonate soils, the soil solution contains calcium bicarbonate, which will primarily participate in the neutralization reaction (as the most mobile) of nitric acid. In addition, in any soil there is a significant amount of exchange-absorbed calcium, which is easily displaced into solution by hydrogen ions of nitric acid with the formation of calcium nitrate.[...]
In laminated paper with sizing with hydrophobic adhesive, intra-fiber diffusion, as experiments show, can occur approximately 1000 times faster than through capillaries, into which hydrophobic particles of the sizing agent prevent the penetration of water. Adding an alkali solution to water facilitates the diffusion of moisture into the thickness of the paper sheet, since alkali promotes the swelling of the fibers and, consequently, the penetration of moisture into the fibers. In addition, the alkali enters into a neutralization reaction with the free resin of rosin glue, as a result of which conditions are created that promote interfiber penetration of moisture. That is why adding an alkaline solution to water also promotes the capillary rise of moisture in strips of paper vertically suspended above the surface of the moisture and touching this surface. [...]
With this method of producing mixtures, they are produced in granular form, which ensures good dispersion and facilitates local application when sowing and planting plants (in rows, holes, furrows). These fertilizers are called complex-mixed fertilizers. To prepare them, take weighed amounts of simple or complex powdered fertilizers (simple or double superphosphate, ammophos or diammophos, ammonium nitrate or urea and potassium chloride) in the desired proportion and mix them thoroughly in a special drum granulator. At the same time, ammonia is added to neutralize the free phosphoric acid of superphosphate. The neutralization reaction proceeds with the release of heat and warming up the mixture, which contributes to its drying. If ammophos or diammophos is not added to the mixture, then it is enriched with liquid phosphoric acid. Thanks to the rotation of the drum, granules are formed from the mixed powdered fertilizers. They are cooled, sifted and treated with water-repellent substances (to prevent dampness). Ready mixtures are packaged in 5-layer paper bags or polyethylene bags. To produce fertilizer mixtures according to this principle, 12 large factories with process automation are being built in the USSR.[...]
However, noting that the electron in basic solvents is “in a free state,” we made some inaccuracy. Of course, such a tiny particle has an electrostatic field of extremely high intensity, and therefore it will attract polar solvent molecules to itself, that is, it will be solvated. The solvated electron is also known in aqueous solutions, where it is formed, for example, when water and aqueous solutions are irradiated by sources of radioactive radiation. But if a solvated electron exists in water for a very short time (there are always enough H30+ ions “at its service” in water for a neutralization reaction to occur: H30+ + £-> Y2H2 ■+ ' + H20), then in strongly basic solvents the solvated electron is very stable . Thus, sodium solutions in liquid ammonia are stored without any changes in physical and chemical properties for several months.[...]
Sulfuric acid from the factory storage facility enters a tank, from where it is supplied by a submersible pump to a pressure tank and then to a drum reactor. In accordance with GOST, the content of free sulfuric acid and insoluble residue in aluminum sulfate is limited. Fulfillment of these requirements in a continuous process is possible with automatic dosing of reagents - a suspension of aluminum hydroxide and sulfuric acid. A centrifugal pump continuously supplies the suspension to a circulation ring, in the upper part of which there is a sampling box. From the selection box, part of the suspension enters a continuous drum reactor, and the excess is drained into a repulpator. Due to the heat of dilution of sulfuric acid and the reaction of neutralization of aluminum hydroxide with acid, the temperature in the reactor is maintained within the range of 95-115 °C. The residence time of the reaction mass in the reactor is 25-40 minutes. The density of the reaction mass is 1500 kg/m3. The productivity of the apparatus is 10,000 kg/h at a drum rotation speed of 0.18 s-1. Upon exiting the reactor, a concentrated solution of aluminum sulfate with 13.5% AlO3 enters the spray nozzles of the fluidized bed granulator.