CN102115421A - Method for producing co-product of pentaerythritol as well as zinc formate and sodium phosphate - Google Patents

Abstract

The invention provides a method for producing co-product of pentaerythritol as well as zinc formate and sodium phosphate, which comprises the steps of: carrying out condensation on formaldehyde and acetaldehyde for preparing the pentaerythritol, then carrying out reduced pressure distillation on the waste liquid obtained by the preparation of the pentaerythritol and forming saturated solution of the pentaerythritol; cooling, filtering and separating the saturated solution of the pentaerythritol, and obtaining pentaerythritol crystal and filtrate I; carrying out reduced pressure distillation on the filtrate I and obtaining saturated solution of sodium formate, cooling, crystallizing and separating out sodium formate, and obtaining sodium formate crystal and filtrate II; washing, drying and grinding the pentaerythritol crystal, and obtaining pentaerythritol product; dissolving the sodium formate crystal into water, leading the water solution to have reaction with zinc phosphate solution, filtering and obtaining filtrate III containing zinc formate and sodium phosphate; carrying out reduced pressure distillation on the filtrate III and forming saturated solution of the zinc formate; cooling, filtering, separating and obtaining zinc formate crystal and filtrate IV; carrying out reduced pressure distillation on the filtrate IV and forming supersaturated solution of sodium phosphate, cooling and obtaining sodium phosphate crystal; and finally, respectively washing, drying and grinding the sodium phosphate crystal and the zinc formate crystal, and respectively obtaining the sodium phosphate and the zinc formate.

Description

A kind of method for preparing tetramethylolmethane coproduction zinc formate and sodium phosphate

Technical field

The present invention relates to the organic chemical industry and produce the improvement of tetramethylolmethane gained waste liquid and the technical field of utilization, especially a kind of method for preparing tetramethylolmethane coproduction zinc formate and sodium phosphate, its raw material is for producing tetramethylolmethane gained waste liquid.

Background technology

Tetramethylolmethane is a kind of organic intermediate of having many uses, and is usually used in coatings industry, is the raw material of alkydpaints, and hardness, glossiness and the weather resistance of paint film are improved; Also be used as the abietinic raw materials such as printing-ink of varnish, colored paint, and can make the coating of flame retardant resistance, siccative oil and aero oil lubricate wet goods.Be that to make the tetramethylolmethane tetranitrate be volatile explosive to raw material with the tetramethylolmethane.The sour fat of tetramethylolmethane fat can be made the softening agent and the stablizer of polyvinyl chloride resin, in addition, also can be used for medicine, agricultural chemicals and lubricated wet goods manufacturing.

Tetramethylolmethane is to be raw material with formaldehyde and acetaldehyde, and condensation makes in the presence of basic catalyst.Be exactly specifically: 37% formaldehyde is under condition of stirring and sodium hydroxide and acetaldehyde, slowly be warming up to 25-32 degree centigrade with steam, keeping this temperature stirred 6-7 hour, the sulfuric acid that adds with mole folding hundred such as sodium hydroxide neutralizes, and the filtrate vapourisation under reduced pressure is concentrated, crystallization, filtration and drying make finished product.

Produce tetramethylolmethane gained waste liquid and come the mother liquor and the washing water of inherent filtration and washing.Contain sodium formiate 25%, tetramethylolmethane 6-8%, other organic substances 15% in the mother liquor.One ton of tetramethylolmethane of every production has 3 cubic metres of crystalline mother solutions to discharge approximately.If by yield 80%, one ton of tetramethylolmethane of then every production is wanted 0.6 ton of by-product sodium formiate.With volume calculation unit be: formic acid ammonium formiate sodium volume content is 300-500 (g/L), tetramethylolmethane volume content 50-100 (g/L), and the mother liquor quantity discharged of producing product per ton is the 2-3 ton.

Discharge arbitrarily or abandon if produce tetramethylolmethane gained waste liquid,, also waste raw material, for this reason, be necessary to explore the comprehensive regulation and methods for using them of producing tetramethylolmethane gained waste liquid without influencing environment.

Summary of the invention

Produce tetramethylolmethane with formaldehyde and acetaldehyde condensation, contain sodium formiate 25wt.%, tetramethylolmethane 6-8wt.%, other organic substances 15wt.% in the gained waste liquid.For to its comprehensive regulation and application, the invention provides a kind of method for preparing tetramethylolmethane coproduction zinc formate and sodium phosphate, its raw material is that formaldehyde and acetaldehyde condensation are produced tetramethylolmethane gained waste liquid.This method, formaldehyde and acetaldehyde condensation are produced tetramethylolmethane gained waste liquid through simple processing treatment, make tetramethylolmethane, zinc formate and sodium phosphate, make full use of formaldehyde and acetaldehyde condensation and produced the potential value of tetramethylolmethane gained waste liquid, and do not produce secondary pollution, being one turns waste into wealth, economic and practical method.

Technical scheme of the present invention is as follows: a kind of method for preparing tetramethylolmethane coproduction zinc formate and sodium phosphate, its raw material are that formaldehyde and acetaldehyde condensation are produced tetramethylolmethane gained waste liquid, comprise the steps:

Steps A: is the tetramethylolmethane saturated solution with formaldehyde and acetaldehyde condensation production tetramethylolmethane gained waste liquid through underpressure distillation, and postcooling, the tetramethylolmethane crystallization is separated out, and separates after filtration, obtains crystals of pentaerythritol and filtrate one; Filtrate one further underpressure distillation is the sodium formiate saturated solution, and postcooling, the sodium formiate crystallization is separated out, and is separating after filtration, obtains sodium formiate crystal and filtrate two;

Step B: the above-mentioned crystals of pentaerythritol that obtains through washing, dry and pulverizing, is obtained the tetramethylolmethane product;

Step C: the above-mentioned sodium formiate crystal that obtains is water-soluble, be 6 with the ratio of the molar content of the pure substance of sodium formiate and zinc phosphate then with zinc phosphate solution: the 0.8-1.2 reaction, produce zinc formate and sodium phosphate, after filtration, remove a spot of filter residue, obtain containing the filtrate three of zinc formate and sodium phosphate;

Step D: filtrate three is the zinc formate saturated solution through underpressure distillation, is cooled to 10 ℃, and at this moment, the saturation ratio of sodium phosphate is 8.2g, the saturation ratio of zinc formate is 4.3g, and therefore, the zinc formate crystallization is separated out, and sodium phosphate separates still in solution after filtration, obtains zinc formate crystal and filtrate four; Filtrate four further underpressure distillation are the sodium phosphate supersaturated solution, are cooled to 10 ℃, and at this moment, the sodium phosphate mass crystallization is separated out, and obtains the sodium phosphate crystal; Sodium phosphate crystal and zinc formate crystal advance washing, dry and pulverizing respectively, thereby obtain sodium phosphate product and zinc formate product respectively.

The method for preparing tetramethylolmethane coproduction zinc formate and sodium phosphate of the present invention, its chemical equation:

6HCOONa+Zn ₃(PO ₄) ₂＝＝＝＝3Zn(COOH) ₂+2Na ₃PO ₄

Beneficial effect of the present invention is: the method for preparing tetramethylolmethane coproduction zinc formate and sodium phosphate of the present invention, formaldehyde and acetaldehyde condensation are produced tetramethylolmethane gained waste liquid through simple processing treatment, make tetramethylolmethane coproduction zinc formate and sodium phosphate, make full use of formaldehyde and acetaldehyde condensation and produced the potential value of tetramethylolmethane gained waste liquid, and do not produce secondary pollution, being one turns waste into wealth, economic and practical method.This method is simple to operate, and facility investment is few, is worthy of popularization.

Embodiment

Embodiment 1:

A kind of method for preparing tetramethylolmethane coproduction formic acid and sodium phosphate, its raw material are that formaldehyde and acetaldehyde condensation are produced tetramethylolmethane gained waste liquid, and wherein, sodium formiate 25wt.%, tetramethylolmethane 7wt.% comprise the steps:

Steps A: formaldehyde and acetaldehyde condensation are produced tetramethylolmethane gained waste liquid 816kg, are the tetramethylolmethane saturated solution through underpressure distillation, and postcooling, the tetramethylolmethane crystallization is separated out, and separates after filtration, obtains crystals of pentaerythritol and filtrate one; Filtrate one further underpressure distillation is the sodium formiate saturated solution, and postcooling, the sodium formiate crystallization is separated out, and is separating after filtration, obtains sodium formiate crystal and filtrate two;

Step B: the above-mentioned crystals of pentaerythritol that obtains through washing, dry and pulverizing, is obtained the tetramethylolmethane product; The quality of the tetramethylolmethane pure substance that it contains is 57.12kg;

Step C: the above-mentioned sodium formiate crystal that obtains is water-soluble, be reaction in 6: 1.2 with the ratio of the molar content of the pure substance of sodium formiate and zinc phosphate then, produce zinc formate and sodium phosphate, after filtration with zinc phosphate solution, remove a spot of filter residue, obtain containing the filtrate three of zinc formate and sodium phosphate;

Step D: filtrate three is the zinc formate saturated solution through underpressure distillation, is cooled to 10 ℃, and at this moment, the saturation ratio of sodium phosphate is 8.2g, the saturation ratio of zinc formate is 4.3g, and therefore, the zinc formate crystallization is separated out, and sodium phosphate separates still in solution after filtration, obtains zinc formate crystal and filtrate four; Filtrate four further underpressure distillation are the sodium phosphate supersaturated solution, are cooled to 10 ℃, and at this moment, the sodium phosphate mass crystallization is separated out, and obtains the sodium phosphate crystal; Sodium phosphate crystal and zinc formate crystal advance washing, dry and pulverizing respectively, thereby obtain sodium phosphate product and zinc formate product respectively, and the quality of the pure substance of the sodium phosphate that it contains is 164kg, and the quality of the pure substance of the zinc formate that it contains is 232.5kg.

Embodiment 2:

A kind of method for preparing tetramethylolmethane coproduction formic acid and sodium phosphate, its raw material are that formaldehyde and acetaldehyde condensation are produced tetramethylolmethane gained waste liquid, and wherein, sodium formiate 25wt.%, tetramethylolmethane 7wt.% comprise the steps:

Steps A: formaldehyde and acetaldehyde condensation are produced tetramethylolmethane gained waste liquid 816kg, are the tetramethylolmethane saturated solution through underpressure distillation, and postcooling, the tetramethylolmethane crystallization is separated out, and separates after filtration, obtains crystals of pentaerythritol and filtrate one; Filtrate one further underpressure distillation is the sodium formiate saturated solution, and postcooling, the sodium formiate crystallization is separated out, and is separating after filtration, obtains sodium formiate crystal and filtrate two;

Step B: the above-mentioned crystals of pentaerythritol that obtains through washing, dry and pulverizing, is obtained the tetramethylolmethane product; The quality of the tetramethylolmethane pure substance that it contains is 57.12kg;

Step C: the above-mentioned sodium formiate crystal that obtains is water-soluble, be reaction in 6: 1 with the ratio of the molar content of the pure substance of sodium formiate and zinc phosphate then, produce zinc formate and sodium phosphate, after filtration with zinc phosphate solution, remove a spot of filter residue, obtain containing the filtrate three of zinc formate and sodium phosphate;

Step D: filtrate three is the zinc formate saturated solution through underpressure distillation, is cooled to 10 ℃, and at this moment, the saturation ratio of sodium phosphate is 8.2g, the saturation ratio of zinc formate is 4.3g, and therefore, the zinc formate crystallization is separated out, and sodium phosphate separates still in solution after filtration, obtains zinc formate crystal and filtrate four; Filtrate four further underpressure distillation are the sodium phosphate supersaturated solution, are cooled to 10 ℃, and at this moment, the sodium phosphate mass crystallization is separated out, and obtains the sodium phosphate crystal; Sodium phosphate crystal and zinc formate crystal advance washing, dry and pulverizing respectively, thereby obtain sodium phosphate product and zinc formate product respectively, and the quality of the pure substance of the sodium phosphate that it contains is 164kg, and the quality of the pure substance of the zinc formate that it contains is 232.5kg.

Embodiment 3:

A kind of method for preparing tetramethylolmethane coproduction formic acid and sodium phosphate, its raw material are that formaldehyde and acetaldehyde condensation are produced tetramethylolmethane gained waste liquid, and wherein, sodium formiate 25wt.%, tetramethylolmethane 7wt.% comprise the steps:

Steps A: formaldehyde and acetaldehyde condensation are produced tetramethylolmethane gained waste liquid 816kg, are the tetramethylolmethane saturated solution through underpressure distillation, and postcooling, the tetramethylolmethane crystallization is separated out, and separates after filtration, obtains crystals of pentaerythritol and filtrate one; Filtrate one further underpressure distillation is the sodium formiate saturated solution, and postcooling, the sodium formiate crystallization is separated out, and is separating after filtration, obtains sodium formiate crystal and filtrate two;

Step B: the above-mentioned crystals of pentaerythritol that obtains through washing, dry and pulverizing, is obtained the tetramethylolmethane product; The quality of the tetramethylolmethane pure substance that it contains is 57.12kg;

Step C: the above-mentioned sodium formiate crystal that obtains is water-soluble, be reaction in 6: 0.8 with the ratio of the molar content of the pure substance of sodium formiate and zinc phosphate then, produce zinc formate and sodium phosphate, after filtration with zinc phosphate solution, remove a spot of filter residue, obtain containing the filtrate three of zinc formate and sodium phosphate;

Step D: filtrate three is the zinc formate saturated solution through underpressure distillation, is cooled to 10 ℃, and at this moment, the saturation ratio of sodium phosphate is 8.2g, the saturation ratio of zinc formate is 4.3g, and therefore, the zinc formate crystallization is separated out, and sodium phosphate separates still in solution after filtration, obtains zinc formate crystal and filtrate four; Filtrate four further underpressure distillation are the sodium phosphate supersaturated solution, are cooled to 10 ℃, and at this moment, the sodium phosphate mass crystallization is separated out, and obtains the sodium phosphate crystal; Sodium phosphate crystal and zinc formate crystal advance washing, dry and pulverizing respectively, thereby obtain sodium phosphate product and zinc formate product respectively, and the quality of the pure substance of the sodium phosphate that it contains is 131.2kg, and the quality of the pure substance of the zinc formate that it contains is 186kg.

Above content be in conjunction with concrete preferred implementation to further describing that the present invention did, can not assert that concrete enforcement of the present invention is confined to these explanations.For the general technical staff of the technical field of the invention, without departing from the inventive concept of the premise, its framework form can be flexible and changeable, can the subseries product.Just make some simple deduction or replace, all should be considered as belonging to the scope of patent protection that the present invention is determined by claims of being submitted to.

Claims (1)

1. a method for preparing tetramethylolmethane coproduction zinc formate and sodium phosphate is characterized in that, its raw material is that formaldehyde and acetaldehyde condensation are produced tetramethylolmethane gained waste liquid, comprises the steps:

Steps A: is the tetramethylolmethane saturated solution with formaldehyde and acetaldehyde condensation production tetramethylolmethane gained waste liquid through underpressure distillation, and postcooling, the tetramethylolmethane crystallization is separated out, and separates after filtration, obtains crystals of pentaerythritol and filtrate one; Filtrate one further underpressure distillation is the sodium formiate saturated solution, and postcooling, the sodium formiate crystallization is separated out, and is separating after filtration, obtains sodium formiate crystal and filtrate two;

Step B: the above-mentioned crystals of pentaerythritol that obtains through washing, dry and pulverizing, is obtained the tetramethylolmethane product;

Step C: the above-mentioned sodium formiate crystal that obtains is water-soluble, be 6 with the ratio of the molar content of the pure substance of sodium formiate and zinc phosphate then with zinc phosphate solution: the 0.8-1.2 reaction, produce zinc formate and sodium phosphate, after filtration, remove a spot of filter residue, obtain containing the filtrate three of zinc formate and sodium phosphate;

Step D: filtrate three is the zinc formate saturated solution through underpressure distillation, is cooled to 10 ℃, and at this moment, the saturation ratio of sodium phosphate is 8.2g, the saturation ratio of zinc formate is 4.3g, and therefore, the zinc formate crystallization is separated out, and sodium phosphate separates still in solution after filtration, obtains zinc formate crystal and filtrate four; Filtrate four further underpressure distillation are the sodium phosphate supersaturated solution, are cooled to 10 ℃, and at this moment, the sodium phosphate mass crystallization is separated out, and obtains the sodium phosphate crystal; Sodium phosphate crystal and zinc formate crystal advance washing, dry and pulverizing respectively, thereby obtain sodium phosphate product and zinc formate product respectively.