RU1796631C - Process for preparing mineral salt deposition inhibitor - Google Patents

Abstract

SUMMARY OF THE INVENTION: reagent 1: caprolactam, reagent 2: formaldehyde, reagent 3: phosphoric acid. Reaction conditions: the molar ratio of reagents 1, 2 and 3 is 1: 1.5-2.5: 1.5-2.5. Subsequent neutralization of the resulting solution to a pH of 3.5-5.0.

Description

The invention relates to the chemistry of organophosphorus compounds, and in particular to a method for producing an inhibitor of the deposition of mineral salts, which are used to control scaling in recycling water supply systems in metallurgical industries and in the power system.

A known method of producing an inhibitor of the deposition of mineral salts by fbsforylation. Ammonia, ethylenediamine ,. diethanolamine and other mono- and diamines, to prevent the precipitation of calcium salts from aqueous solutions, it has been proposed to add salts of polyalkylene polyaminopolymethylene acid.

There is also known a method for producing an inhibitor of the deposition of calcium carbonate and sulfate salts by reacting formaldehyde and phosphorous acid in a hydrochloric acid medium with a mixture of polyethylene polyamine, monoethanolamine, carbamide, ammonium chloride and hexamethylenetetramine.

The disadvantages of the known methods are the low efficiency of inhibiting products at concentrations of less than 5 mg / L and the high cost.

The closest to the invention in technical essence and the achieved result is a method for producing an inhibitor of deposits of mineral salts by the interaction of phosphorous acid, formaldehyde and a mixture of polyethylene polyamine, ethylene diamine and hexamethylenetetramine or hydrochlorides of these amines, which are a waste in polynoids 6 AN-19, AN-22 and AN-21.

The disadvantage of this method is the low efficiency of inhibition at concentrations of less than 5 mg / l and the required

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about s

bridging strict regulation of the ratio of various amines, while anion exchangers are produced in single batches.

The aim of the invention is to increase the efficiency of inhibiting the deposition of mineral salts.

The goal is achieved by using caprolactam as the amino compound and the process is carried out at a molar ratio of caprolactam, phosphorus-containing compound and formaldehyde equal to 1.0: 1.5-2.5: 1.5-2.5.

The phosphorylation process is carried out in an aqueous hydrochloric acid medium by the interaction of formaldehyde and phosphorus trichloride with aminocaproic acid formed in this medium. After carrying out the phosphorylation reaction, the resulting product is neutralized by the addition of sodium hydroxide and the resulting aqueous solution containing 25-30% of the inhibitor, 4-5% sodium chloride is cooled to room temperature.

The inhibitor reaction scheme can be depicted as follows:

to-vzh

1. PCljt-3HtO- HjPOj + 3HC1tZ02Q

HG-RS

HC1

d. co (cng) ;; W + h7o - shoe (cng) 5mng 5. Hooc (cH sMH iHjPo5 + gsngo-

(M.Q

cng o (otfl2 g: - ™; ™ measured -,:,.,

lngrooya. - - NaOOCtCHiVNQ + 5НгО g хШрРООЫа

The final product is the sodium salt of aminocaproic M.M-dimethylenephosphonic acid, conditionally called an inhibitor

AFC. - -.:. ; V.-V -...:. . -; Example 1. 155.7 kg of 3.1.6% hydrochloric acid, 88.1 kg (0.78 kg-mol) of cz-pro-lactame are charged into an enameled reactor equipped with a reflux condenser and a stirrer. and stirred at a temperature of 50 ° C for 3 h, then 218.8 kg (1.58 kg mol) of trichloride phosphorus and 126.5 kg (1.55 kg mol) of 37.0% formalin are introduced, the temperature of the mixture gradually rise to 100 ° and incubated at 100-105 ° C for 8 hours (with a ratio of caprolactam. phosphorus trichloride: formalin 1: 2: 2). The evolved hydrogen chloride is collected in a scrubber. After the completion of the phosphorylation reaction, the contents in the reactor are cooled to 50 ° C and 282.7 kg of 43% sodium hydroxide are gradually introduced at this temperature. As a result, 1000 kg of a 30% aqueous solution of an ROS inhibitor, pH 5.0, are obtained. The yield of product is 94.0%.

PRI me R 2. In an enameled reactor equipped with a reflux condenser and

with a stirrer, load 155.7 kg of 31.6% hydrochloric acid, 88.1 kg (0.78 kg mol) of caprolactam and stir at 50 ° C for 3 hours, then 162 kg are introduced (1, 17 kg mol) of phosphorus trichloride and 94.0 kg

(1.17 kg mol) of 37% formalin (1.0: 1.5: 1.5), the temperature of the mixture was gradually raised to .TOO0С and kept at 100-105 ° for 8 hours. The evolved hydrogen chloride was collected in a scrubber . After the completion of the phosphorylation reaction, the contents in the reactor are cooled to 50 ° C and 212 kg of 43% sodium hydroxide are gradually introduced at this temperature. The result is a 20% aqueous solution of an ROS inhibitor, pH 4.0. Yield 65%.

PRI me R 3. The phosphorylation reaction is carried out under the above conditions with a molar ratio of caprolacts: phosphorus trichloride: formalin

1.0: 2.5: 2.5. The result is 100 kg of a 30% aqueous solution of ROS, pH 3.5. Product yield 92%

Example 4. The phosphorylation reaction is carried out under the conditions described above.

at a molar ratio of caprolacts: phosphorous acid: formalin 1: 2: 2, As a result, 1000 kg of a 30% aqueous solution of the inhibitor are obtained, pH 3.5. The product yield is 95%.

The properties of the obtained inhibitors of mineral salt deposits are presented in Table 1. The effectiveness of inhibition of calcium salt deposits was determined in accordance with TU 6-05-211-1159-80.

: -Thus, it can be seen from the above data that, at a concentration of 1 mg / L, the ROS inhibitor of Example 1, 4 excels the known inhibition efficiency of calcium sulfate and calcium carbonate.

inhibitor.

. The proposed ROS inhibitor was used to prevent deposits of mineral salts from recycled water in metallurgical industries.

When carrying out tests under conditions

Agropromsmzvodstva Karaganda Metallurgical Plant in the circulating water of the ROS inhibitor was administered in doses of 1.0-3.0

mg / l of water. The inhibitory effect of the reagent was determined by the weight method from the weights of the plates; sumps lowered into trays. During the test period of the ROS inhibitor (after 12 days), deposits were observed

0.0216 mm / year, while without reagent, it is 2.64 mm / year.

Recycled waters of the KerMK agro-production have a complex salt composition, and the pH reaches 12.5. .

The proposed ROS inhibitor, in addition to stabilizing recycled water, removes old deposits found in pipelines and components of the equipment and pump station.

Effect of an ROS inhibitor. the salt composition of recycled water is given in table.2.

As can be seen from the table, in the circulating water, the calcium content decreases by 100 mg / L, and the sulfate increases by 120 mg / L.

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Thus, from the above examples, we can conclude that the proposed method has a significant effect on preventing the deposition of mineral salts of metallurgical industries. Using the proposed method in comparison with existing methods has the following advantages:

increased inhibition of deposits at low inhibitor concentrations; .....

cheaper product using less expensive starting components;

reducing the cost of the process by replacing the expensive DFT inhibitor, IOMS and reducing the amount of inhibitor used.

Claims (1)

The formula is invented by E.N. and a Method for producing an inhibitor of deposits of mineral salts by reacting an amino compound with formaldehyde and phosphorous, acid or phosphorus trichloride in an aqueous hydrochloric acid medium, followed by neutralization of the resulting solution to pH 3.5-5.0, The fact is that, with a whole increase in the effectiveness of the inhibitor, caprolactam is used as an amino compound .. - the process is carried out at a molar ratio of caprolactam, phosphorus-containing compound and formaldehyde of 1: 1.5-2.5: 1.5-2, 5. Table 1 table 2