Purification method of triethylene tetraamine base hexamethylene phosphonic acid

[0022] Add 125 mL of pure water into a 500 mL three-necked bottle, start stirring, add 25 g of TTHMP crude product to dissolve, adjust the pH to pH>12 with 4mol / L sodium hydroxide aqueous solution, add 250 mL of ethanol, let it stand for 4 hours, and collect the precipitated Oil I.

[0023] Add 125 mL of pure water into a 500 mL three-necked bottle, start stirring, add oil I to dissolve, heat to reflux, add 37.5 mL of ethanol to make the solution cloudy, keep the reflux state, add 3 mL of water until the solution is clear, stop heating and stirring, After cooling to room temperature and standing for 12 hours, the precipitated oil II was collected. This step was repeated 3 times, and the separated oil III was collected.

[0024] Add 125 mL of pure water into a 500 mL three-necked flask, start stirring, add oil III to dissolve, add 10% hydrochloric acid aqueous solution to adjust pH<2, add 62.5 mL of ethanol, let stand for 4 hours, and collect the precipitated oil IV.

[0025]

[0027] Add 125 mL of pure water into a 500 mL three-necked bottle, start stirring, add 25 g of TTHMP crude product to dissolve, adjust the pH to pH>12 with 4mol / L sodium hydroxide aqueous solution, add 250 mL of methanol, let it stand for 4 hours, and collect the precipitated Oil I.

[0028] Add 125 mL of pure water into a 500 mL three-neck flask, start stirring, add oily substance I to dissolve, heat to reflux, add 37.5 mL of methanol to make the solution cloudy, keep the reflux state, add 3 mL of water until the solution is clear, stop heating and stirring, After cooling to room temperature and standing for 12 hours, the precipitated oil II was collected. This step was repeated 3 times, and the separated oil III was collected.

[0029] Add 125 mL of pure water into a 500 mL three-neck flask, start stirring, add oily substance III to dissolve, add 10% hydrochloric acid aqueous solution to adjust pH<2, add 62.5 mL of methanol, let it stand for 4 hours, and collect the precipit

[0032] Add 125 mL of pure water into a 500 mL three-necked flask, start stirring, add 25 g of crude TTHMP to dissolve, adjust the pH to pH>12 with 4mol / L aqueous sodium hydroxide solution, add 250 mL of isopropanol, let stand for 4 hours, collect Precipitated oil I.

[0033] Add 125 mL of pure water into a 500 mL three-neck flask, start stirring, add oily substance I to dissolve, heat to reflux, add 37.5 mL of isopropanol to make the solution cloudy, keep the reflux state, add 3 mL of water until the solution is clear, stop heating and Stir, cool to room temperature and let stand for 12 hours, and collect the precipitated oil II. This step was repeated 3 times, and the separated oil III was collected.

[0034] Add 125 mL of pure water into a 500 mL three-neck flask, start stirring, add oily substance III to dissolve, add 10% hydrochloric acid aqueous solution to adjust pH<2, add 62.5 mL of isopropanol, let stand for 4 hours, and collect the precipitated oily substance IV.

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