RU2434875C1 - Polyalkylene polyamine polymethylphosphonic acid synthesis method - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: invention relates to a method of producing polyalkylene polyamine polymethylphosphonic acids used as mineral salt deposit inhibitors in heating systems, hot water supply systems and water collection systems of industrial plants. The method involves obtaining polyalkylene polyamine polymethylphosphonic acids, selected from nitrilotrimethylphosphonic acid, methyliminodimethylphosphonic acid, ethylenediamine tetramethylphosphonic acid, hexamethylene diamine tetramethylphosphonic acid, diethylene triamine pentamethylphosphonic acid and triethylene tetraamine hexamethylphosphonic acid, by reacting the corresponding amine or corresponding ammonium compounds with formaldehyde and phosphorous acid in a chloride solution while boiling and then cooling the reaction mass and extracting the end product in solid form, wherein formaldehyde (in form of formalin) is used in 5-7% excess compared to stoichiometry, and the reaction process is carried out at defined conditions for adding starting reagents, where phosphorus acid, hydrochloric acid and formalin are added first, and the corresponding amine or ammonium compound is then added to the formed reaction mixture while stirring for 3-5 minutes.

EFFECT: method simplifies the technique, reduces power consumption, widens the range and increases output of polyalkylene polyamine polymethylphosphonic acids.

3 cl, 8 ex

Description

The invention relates to the chemistry of organophosphorus compounds, in particular to the production of aminophosphonates used as inhibitors of mineral salt deposits for stabilizing water treatment in water supply systems of metallurgical, chemical, petrochemical and other industries, as well as in heating and hot water systems.

Polyalkylene polyamine polymethylphosphonic acids have the general formula:

where n = 2; 6;

R '= alkylene radical containing from 2 carbon atoms, m = 1; ≥2.

The group of polyalkylene polyamine polymethylphosphonic acids, in particular, includes the following acids:

- nitrilotri (methylphosphonic acid) (NTP),

- methyliminodi (methylphosphonic acid) (MIDP),

- hexamethylene diamine tetra (methylphosphonic acid) (GMDTF),

- ethylene diamine tetra (methylphosphonic acid) (EDTP),

- diethylene triamine penta (methylphosphonic acid) (EDTP),

- triethylenetetraaminex (methylphosphonic acid) (TSHF).

The main method for preparing these compounds is based on the reaction of the interaction of ammonia or amines with formaldehyde and phosphorous acid, as such, or with the product of hydrolysis of phosphorus trichloride or saponification of dialkyl phosphites in a hydrochloric acid medium. This method is widely described as in patent documentation (SU 992519, C07F 9/38, 1982; SU 992519, C07F 9/38, 1983; SU 709545, C01G 51/06, 1979; RU 2133751, C07F 9/38, 1999; RU 2168514, C07F 9/38, 2001; RU 2329270, C07F 9/38, 2007) and the documentation (SU 992519, C07F 9/38, 1982; SU 709545, C01G 51/06, 1979; RU 2133751, C07F 9 / 38, 1999; RU 2168514, C07F 9/38, 2001; RU 2329270, C07F 9/38, 2007), as well as in the scientific and technical literature (Kabachnik M.I., Medved T.Ya., Dyatlova N.M. , Rudomino M.V. / Advances in Chemistry. 1974. T.43. No. 9. S.1554-1574). So, to obtain NTF, ammonium methylphosphorylation (in the form of ammonium chloride) is carried out with formaldehyde and phosphorous acid in hydrochloric acid when the reaction solution is heated to a temperature of 75-200 ° C (Rajendran S., Amalraj AE, et al. Transactions of the SAEST, 2005 , v.40, No. 1, p. 35-39; CA 2006, v. 144, 296504).

Similarly, methylphosphorylation of hexamethylenediamine gives HMDTP (Zhon Chen, Zhang Baosheng et al. / Fushi Yu Fanghu. 2004. V.25, No. 4, p.146-148; CA 2006, v.145, 12114) and methylphosphorylated derivatives of various other aliphatic polyamines including EDTP, DTPF, TTGF, PPPF (Yin X. et al. / Xian Shiyou Xueynau Xuebao, 1997, v.12, No. 2, p.50-51; CA 1997, v.126, 320836f) /.

It should be noted that the molar ratio of the starting reagents has a significant effect on the yield and composition of the resulting product. So, in methods that are protected as methods for producing inhibitors of deposits of mineral salts, molar ratios of ammonia: formaldehyde: phosphorous acid are used: 1.0: 2.35-2.65: 2.2-2.4 (RU 2133751), ammonium chloride: hexamethylenediamine: formaldehyde: phosphorous acid 3.0-6.0: 1: 10.9: 10.95 (RU 2329270).

The methylphosphorylation process is carried out by classical methods at elevated temperatures, preferably in the range of 50-105 ° C.

The sequence of introducing reagents into the reaction in the known known methods is the same: at the first stage phosphorous and hydrochloric acids are introduced, then ammonia (usually in the form of hydrochloric acid salt - ammonium chloride) or an aliphatic amine and at the final stage slowly add formalin at an elevated temperature up to the temperature boiling.

As a prototype of the new method for the preparation of individual compounds, a well-known method for the production of methylphosphorylated ammonia derivative nitrilotrimethylphosphonic acid (NTP) (Sidorenko V.V., Lapshina N.V., Konopleva TP / Methods for the production of chemical reagents and preparations. - M .: IREA. 1971. Issue 23. P.86); (Rajendran S., Amalraj A.E. et al. / Transaction of the SAETS. 2005. V.40. No. 1. P.35-39; C.A. 2006. V.144. 296504).

Into a glass flask, 99.2 g of a 49.6% aqueous phosphorous acid solution (0.6 mol, calculated as 100% acid) are charged and with stirring in small portions 57 ml of 37% hydrochloric acid. Then, 10.6 g (0.2 mol) of ammonium chloride are sprinkled with. The resulting mixture was heated to 105 ° C, 51.4 g (0.6 mol) of a 36% aqueous formaldehyde solution were added dropwise in 1 hour.

The reaction mass is stirred for 1 hour at the same temperature, and after filtration and evaporation 30 g of NTP are isolated (yield 46.1%). The molar ratio: ammonium chloride: phosphorous acid: formaldehyde 1: 3: 3.

In order to obtain NTF and methylphosphorylated derivatives of aliphatic polyamines, a new method has been developed in which methylphosphorylation is carried out with formaldehyde and phosphorous acid in a hydrochloric acid solution at the boil using 5-7% excess molar amount of formaldehyde (compared with phosphorous acid), and at a certain sequence introducing into the reaction of the starting reagents, phosphorous and hydrochloric acids and formalin are first introduced, then, with stirring, for 3-5 minutes, add to the reaction mixture vlyayut ammonia (an aqueous solution) or an aliphatic polyamine.

As the latter, ethylene diamine, diethylene triamine, hexamethylene diamine, triethylenetetraamine are used.

In the new method, as in the prototype, phosphorous and hydrochloric acids, formaldehyde (in the form of formalin) and ammonia (in the form of its hydroxide), as well as a number of aliphatic polyamines are used as starting reagents. At the same time, the molar ratio of reagents was changed, where instead of the stoichiometric amount of formaldehyde according to the reaction, as in the prototype method, its 5-7% excess molar amount is used (compared to the molar amount of phosphorous acid), which increases the yield of final products.

Experimental studies have shown that a certain mode and sequence of introducing the initial reagents into the reaction has a significant effect on the methylphosphorylation process. In the case when the aliphatic polyamine or ammonia in the form of hydroxide is the last to be added to the mixture of phosphorous, hydrochloric acids and formaldehyde (in the form of formalin), and the addition is carried out for 3-5 minutes, an exothermic reaction occurs, and the reaction mixture boils without additional heating . This leads to a decrease in the energy intensity of the process, as well as to an increase in its controllability, which makes the process more technologically advanced.

The following are examples illustrating the invention.

Example 1 (control), reflecting the method of obtaining NTF, not containing the hallmarks of the new invention and taken as a prototype (Sidorenko V.V., Lapshina N.V., Konopleva TP / Methods for the production of chemicals and drugs. - M. : IREA. 1971. Vol. 23, p. 86).

Into a glass flask, 99.2 g of a 49.6% aqueous phosphorous acid solution (0.6 mol, calculated as 100% acid) are charged and with stirring in small portions 57 ml of 37% hydrochloric acid. Then, 10.6 g (0.2 mol) of ammonium chloride are sprinkled with. The resulting mixture was heated to boiling (105 ° C), 51.4 g (0.6 mol) of a 36% aqueous formaldehyde solution were added dropwise in 1 h.

The reaction mass is stirred for another hour at the boil, filtered, the filtrate is evaporated and 30 g of NTF are isolated (46.1% yield). The molar ratio: ammonium chloride: phosphorous acid: formaldehyde corresponds to a value of 1: 3: 3.

Example 2 (control), reflecting the method of obtaining GMDTF, not containing the hallmarks of the new invention. (RF patent №2329270 dated 02.02.2007).

250 g of a 65% aqueous phosphorous acid solution (1.98 mol in terms of 100%) and 34.5 ml of hydrochloric (35%) acid are charged into a glass flask. 84.9 g of an aqueous solution of hexamethylenediamine (HMDA) [57.4 g of HMDA (0.495 mol) in 27.5 ml of water] are charged to the resulting acid mixture with cooling and stirring for (0.1-1.0) hours, maintaining the temperature of the reaction mass is not higher than (50-55) ° C, then 147.3 ml (160.5 g) of 37% formalin (1.98 mol of formaldehyde) are added at (0.3-0.5) h at this temperature . The resulting reaction solution is heated with stirring to a boil of (101-103) ° C and boiled for (1.0-1.5) hours. HMDTP is isolated from the cooled solution. After washing off hydrochloric acid, 165.6 g of acid are obtained. Yield 68.0%. The molar ratio of hexamethylene diamine: phosphorous acid: formaldehyde 1: 4: 4.

Example 3 (according to the invention)

The method of obtaining NTF

378.5 g of 65% phosphorous acid (3.0 mol per 100%), 34.0 cm ^{3 of} 37% hydrochloric acid and 255.4 g (3.15 mol in in terms of formaldehyde, 5% excess compared to H ₃ PO ₃ ). While stirring for 3 minutes, 68.0 g of ammonium hydroxide (1 mol in terms of the 25% content of the basic substance in it) are poured into the resulting mixture. The reaction solution boils. At the end of boiling, the reaction solution was cooled to (50-60) ° C, filtered off, the filtrate was evaporated and 224.3 g of NTP were isolated (75% yield). The molar ratio of ammonium hydroxide: phosphorous acid: formaldehyde corresponds to a value of 1: 3: 3.15.

Example 4 (according to the invention)

The method of obtaining NTF

The method is carried out analogously to example 2 with the following essential feature of the method: the loading time of a 25% aqueous solution of ammonium hydroxide is 5 minutes

Obtain 218.3 g of NTF (yield 73%).

Example 5 (according to the invention)

The method of obtaining NTF

The method is carried out analogously to example 2 with the following essential feature of the method: the molar ratio of ammonium hydroxide: phosphorous acid: formaldehyde corresponds to a value of 1: 3: 3.21 (7% excess compared to H ₃ PO ₃ ).

217.7 g are obtained (yield 74.8%).

Example 6 (according to the invention)

The method of obtaining GMDTF

In a glass flask with a capacity of 2 dm ³ , equipped with a mechanical stirrer, reflux condenser, thermometer and dropping funnel and placed in a cooling bath, 656.0 g of 65% phosphoric acid, 88.0 cm ^{3 of} 37% hydrochloric acid are charged and 451.2 g of formalin (5.56 moles in terms of formaldehyde). Then, stirring is started and 150.8 g (1.3 mol) of hexamethylenediamine are added in 70 cm ^{3 of} water for 3-5 minutes. At the end of the loading of the amine solution, the temperature rises and the mass boils (101-103) ° C. After boiling at a temperature of (90-85) ° C, cooling is turned on and at a temperature of (35-40) ° C, the reaction solution is transferred to a beaker and, with stirring, cooled to (18-20) ° C. After 5 h, the precipitate formed is filtered off and washed on a filter with methanol from Cl ^- .

479.8 g of GMDTF are obtained (75% yield).

Example 7 (according to the invention)

The method of obtaining DTPF

In a glass flask with a capacity of 1 dm ³ , equipped with a mechanical stirrer, reflux condenser, thermometer and dropping funnel and placed in a bath with cooling, load 227.0 g of 65% phosphorous acid (1.8 mol in terms of 100%) , 30.5 cm ^{3 of} 37% hydrochloric acid and 155.7 g of formalin (1.92 moles in terms of formaldehyde). Then, stirring is started and 37.1 g (0.36 mol) of diethylene triamine are added for 3-5 minutes. At the end of the loading of the amine solution, the temperature rises and the mass boils (101-103) ° C. After boiling at a temperature of (90-85) ° C, cooling is turned on and at a temperature of (45-50) ° C, the reaction solution is filtered off and evaporated under reduced pressure. 700 cm ^{3 of} methyl alcohol are added to the residue. The precipitate formed is separated by decantation and DTPP is isolated by a known method.

Obtain 147.3 g of DTPP (yield 72%).

Example 8 (according to the invention)

The method of obtaining EDTP

In a glass flask with a capacity of 0.5 dm ³ , equipped with a mechanical stirrer, reflux condenser, thermometer and dropping funnel and placed in a bath with cooling, load 164 g of 65% phosphoric acid (1.3 mol in terms of 100%) , 22 cm ^{3 of} 37% hydrochloric acid and 112.8 g of formalin (1.39 mol in terms of formaldehyde). Then include stirring and poured for 3-5 minutes 19.5 g (0.325 mol) of ethylenediamine. At the end of the amine loading, the temperature rises and the mass boils (101-103) ° С. After boiling at a temperature of (90-85) ° C, cooling is turned on and at a temperature of (40-45) ° C, the reaction solution is filtered off and evaporated under reduced pressure. 400 cm ^{3 of} methyl alcohol are added to the residue. The precipitate formed is separated by decantation and EDTP is isolated by a method similar to that for the isolation of DTPP.

Obtain 102.0 g of EDTF (yield 72.0%).

Thus, the new method allows to obtain individual aminomethylphosphonic acids with higher yields compared to previously known methods for producing similar acids. In addition, the present method is low-energy in connection with the use of internal energy released during exothermic reactions: the interaction of an amine (ammonia) with mineral acids and methylphosphorylation proper.

Claims (3)

1. A process for preparing polialkilenpoliaminpolimetilfosfonovyh acids selected from nitrilotrimetilfosphonic acid metiliminodimetilfosfonovoy acid etilendiamintetrametilfosfonovoy acid geksametilendiamintetrametilfosfonovoy acid dietilentriaminpentametilfosfonovoy acid trietilentetraamingeksametilfosfonovoy acid by reacting the corresponding amine or the corresponding ammonium compounds with formaldehyde and phosphorous acid in hydrochloric acid at reflux, followed by cooling the reaction solid mass and the isolation of the target product in solid form, characterized in that formaldehyde (in the form of formalin) is used in 5-7% excess compared with stoichiometry, and the interaction process is carried out under a certain mode of introduction of the starting reagents, in which phosphorous is first introduced and hydrochloric acid and formalin, and then the corresponding amine or ammonium compound is added to the resulting reaction mixture with stirring over 3-5 minutes. 2. The method according to claim 1, characterized in that as amines use compounds from the group: hexamethylenediamine, ethylenediamine, diethylenetriamine, triethylenetetramine. 3. The method according to claim 1, characterized in that the ammonium compound is ammonium hydroxide.