Process for preparing trisodium phosphate from glyphosate mother liquid

Abstract

The invention provides a process for directly preparing trisodium phosphate from glyphosate mother liquid in order to effectively recover phosphorus resources from the mother liquid for producing trisodium phosphate. The process is characterized by comprising the following steps: oxidizing the glyphosate mother liquid through catalytic air, oxidizing organic phosphine in the mother liquid into orthophosphate ions, adding sodium hydroxide or sodium carbonate into the mother liquid to adjust the pH value to be 9-10, cooling to be -5 DEG C to 8 DEG C while stirring, crystallizing, separating, washing, and drying to obtain trisodium phosphate. The process is simple and easy for industrialization applications, the obtained trisodium phosphate is wide in application range, difficulty in enabling the glyphosate mother liquid subjected to terminal treatment to reach the emission standard is lowered, and treated solid waste is reduced.

Description

technical field

[0001] The invention relates to a process for treating glyphosate mother liquor, in particular to a process for producing trisodium phosphate by using glyphosate mother liquor. Background technique

[0002] Since glyphosate has a certain solubility in water, a certain amount of glyphosate mother liquor will inevitably be produced. About 5.2 tons of dilute mother liquor is produced per ton of glycine glyphosate, containing about 1.0% glyphosate, about 10% sodium chloride and other impurities. Therefore, the research on the treatment and utilization technology of glyphosate mother liquor has always An important part of phosphine technology research.

[0003] Glyphosate mother liquor is very difficult to handle due to its complex composition and high content of refractory organic matter. The foreign production process adopts the treatment method of concentrated deep burial (such as Monsanto Company in the United States), and there is no introduction of other t...

Examples

Embodiment 1

[0023] The process of producing trisodium phosphate by using glyphosate mother liquor. After the glyphosate mother liquor is oxidized by catalytic air, the organic phosphine in the mother liquor is oxidized to orthophosphate ion, and then sodium hydroxide or sodium carbonate is added to the mother liquor to adjust the pH value. to 9, cooled to -5°C with stirring, crystallized, separated, washed and dried to obtain trisodium phosphate.

Embodiment 2

[0025] The process of producing trisodium phosphate by using glyphosate mother liquor. After the glyphosate mother liquor is oxidized by catalytic air, the organic phosphine in the mother liquor is oxidized to orthophosphate ion, and then sodium hydroxide or sodium carbonate is added to the mother liquor to adjust the pH value. to 10, cooled to 8°C with stirring, crystallized, separated, washed and dried to obtain trisodium phosphate.

[0026] The catalytic air oxidation refers to first heating the glyphosate mother liquor to 110°C and entering the reactor, the reactor is equipped with a catalytic catalyst and a heating electric furnace, the reaction temperature is 200°C, the reaction pressure is 5Mpa, and the liquid-to-air ratio is 1 : 120, the reaction time is 15min.

Embodiment 3

[0028] The process of producing trisodium phosphate by using glyphosate mother liquor. After the glyphosate mother liquor is oxidized by catalytic air, the organic phosphine in the mother liquor is oxidized to orthophosphate ion, and then sodium hydroxide or sodium carbonate is added to the mother liquor to adjust the pH value. to 9.5, cooled to 12°C with stirring, crystallized, separated, washed and dried to obtain trisodium phosphate.

[0029] The catalytic air oxidation refers to first heating the glyphosate mother liquor to 115°C and entering the reactor, the reactor is equipped with a catalytic catalyst and a heating electric furnace, the reaction temperature is 300°C, the reaction pressure is 9Mpa, and the liquid-to-air ratio is 1 : 200, the reaction time is 5min.

[0030] The stirring speed is 20 rpm.

technical field

[0001] The invention relates to a process for treating glyphosate mother liquor, in particular to a process for producing trisodium phosphate by using glyphosate mother liquor. Background technique

[0002] Since glyphosate has a certain solubility in water, a certain amount of glyphosate mother liquor will inevitably be produced. About 5.2 tons of dilute mother liquor is produced per ton of glycine glyphosate, containing about 1.0% glyphosate, about 10% sodium chloride and other impurities. Therefore, the research on the treatment and utilization technology of glyphosate mother liquor has always An important part of phosphine technology research.

[0003] Glyphosate mother liquor is very difficult to handle due to its complex composition and high content of refractory organic matter. The foreign production process adopts the treatment method of concentrated deep burial (such as Monsanto Company in the United States), and there is no introduction of other t...

Examples

Embodiment 1

[0023] The process of producing trisodium phosphate by using glyphosate mother liquor. After the glyphosate mother liquor is oxidized by catalytic air, the organic phosphine in the mother liquor is oxidized to orthophosphate ion, and then sodium hydroxide or sodium carbonate is added to the mother liquor to adjust the pH value. to 9, cooled to -5°C with stirring, crystallized, separated, washed and dried to obtain trisodium phosphate.

Embodiment 2

[0025] The process of producing trisodium phosphate by using glyphosate mother liquor. After the glyphosate mother liquor is oxidized by catalytic air, the organic phosphine in the mother liquor is oxidized to orthophosphate ion, and then sodium hydroxide or sodium carbonate is added to the mother liquor to adjust the pH value. to 10, cooled to 8°C with stirring, crystallized, separated, washed and dried to obtain trisodium phosphate.

[0026] The catalytic air oxidation refers to first heating the glyphosate mother liquor to 110°C and entering the reactor, the reactor is equipped with a catalytic catalyst and a heating electric furnace, the reaction temperature is 200°C, the reaction pressure is 5Mpa, and the liquid-to-air ratio is 1 : 120, the reaction time is 15min.

Embodiment 3

[0028] The process of producing trisodium phosphate by using glyphosate mother liquor. After the glyphosate mother liquor is oxidized by catalytic air, the organic phosphine in the mother liquor is oxidized to orthophosphate ion, and then sodium hydroxide or sodium carbonate is added to the mother liquor to adjust the pH value. to 9.5, cooled to 12°C with stirring, crystallized, separated, washed and dried to obtain trisodium phosphate.

[0029] The catalytic air oxidation refers to first heating the glyphosate mother liquor to 115°C and entering the reactor, the reactor is equipped with a catalytic catalyst and a heating electric furnace, the reaction temperature is 300°C, the reaction pressure is 9Mpa, and the liquid-to-air ratio is 1 : 200, the reaction time is 5min.

[0030] The stirring speed is 20 rpm.