CN102120716A - Method for preparing pentaerythritol along with zinc formate and sodium sulfide - Google Patents

Abstract

The invention provides a method for preparing pentaerythritol along with zinc formate and sodium sulfide. The method comprises the following steps: using the production waste liquid of pentaerythritol prepared from formaldehyde and acetaldehyde to perform reduced pressure distillation and obtain pentaerythritol saturated solution, cooling, performing filtering separation to obtain pentaerythritol crystals and filtrate 1; washing, drying and grinding pentaerythritol crystals to obtain a pentaerythritol product; perform reduced pressure distillation to the filtrate 1 to obtain sodium formate saturated solution, cooling, performing filtering separation to obtain sodium formate crystals, dissolving sodium formate crystals in water, reacting with zinc sulfide solution, filtering to obtain clear filtrate 3; and distilling and cooling the filtrate 3 to crystallize and obtain the mixed product of zinc formate and sodium sulfide.

Description

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

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 sulphite, 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: the sodium formiate 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 sulphite, 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 sulphite, 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 sulphite, 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, it is 2 with the ratio of the molar content of the pure substance of sodium formiate and zinc sulphide then: the 0.8-1.2 reaction with zinc sulphide solution, obtain containing the solution of zinc formate and sodium sulphite, after filtration, obtain extremely a spot of filter cake impurity and clarifying filtrate three;

Step D: filtrate three is through distillation, and cooling, crystallization are separated out, and obtain zinc formate and sodium sulphite mixing prod.

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

2HCOONa+ZnS＝＝＝＝Zn(HCOO) ₂+Na ₂S

Beneficial effect of the present invention is: the method for preparing tetramethylolmethane coproduction zinc formate and sodium sulphite 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 sulphite, 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 zinc formate and sodium sulphite, 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 544kg, 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 38.08kg;

Step C: the above-mentioned sodium formiate crystal that obtains is water-soluble, be reaction in 2: 1.2 with the ratio of the molar content of the pure substance of sodium formiate and zinc sulphide then with zinc sulphide solution, obtain containing the solution of zinc formate and sodium sulphite, after filtration, obtain extremely a spot of filter cake impurity and clarifying filtrate three;

Step D: filtrate three is through distillation, and cooling, crystallization are separated out, and obtain zinc formate and sodium sulphite mixing prod; The quality of the pure substance of the sodium sulphite that it contains is 78kg, and the quality of the pure substance of the zinc formate that it contains is 155kg.

Embodiment 2:

A kind of method for preparing tetramethylolmethane coproduction zinc formate and sodium sulphite, 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 544kg, 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 38.08kg;

Step C: the above-mentioned sodium formiate crystal that obtains is water-soluble, be reaction in 2: 1 with the ratio of the molar content of the pure substance of sodium formiate and zinc sulphide then with zinc sulphide solution, obtain containing the solution of zinc formate and sodium sulphite, after filtration, obtain extremely a spot of filter cake impurity and clarifying filtrate three;

Step D: filtrate three is through distillation, and cooling, crystallization are separated out, and obtain zinc formate and sodium sulphite mixing prod; The quality of the pure substance of the sodium sulphite that it contains is 78kg, and the quality of the pure substance of the zinc formate that it contains is 155kg.

Embodiment 3:

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

Steps A: formaldehyde and acetaldehyde condensation are produced tetramethylolmethane gained waste liquid 544kg, 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 38.08kg;

Step C: the above-mentioned sodium formiate crystal that obtains is water-soluble, be reaction in 2: 0.8 with the ratio of the molar content of the pure substance of sodium formiate and zinc sulphide then with zinc sulphide solution, obtain containing the solution of zinc formate and sodium sulphite, after filtration, obtain extremely a spot of filter cake impurity and clarifying filtrate three;

Step D: filtrate three is through distillation, and cooling, crystallization are separated out, and obtain zinc formate and sodium sulphite mixing prod; The quality of the pure substance of the sodium sulphite that it contains is 62.4kg, and the quality of the pure substance of the zinc formate that it contains is 124kg.

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 sulphite 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, it is 2 with the ratio of the molar content of the pure substance of sodium formiate and zinc sulphide then: the 0.8-1.2 reaction with zinc sulphide solution, obtain containing the solution of zinc formate and sodium sulphite, after filtration, obtain extremely a spot of filter cake impurity and clarifying filtrate three;

Step D: filtrate three is through distillation, and cooling, crystallization are separated out, and obtain zinc formate and sodium sulphite mixing prod.