阅读说明：本技术 一种混合型重金属捕捉剂的合成方法 (Synthetic method of mixed heavy metal capture agent ) 是由 王涛 徐亚军 景奇超 于 2019-09-05 设计创作，主要内容包括：本发明公开了一种混合型重金属捕捉剂的合成方法,包括以下步骤：S1取样：取二硫化碳、苛性碱和有机混合胺待用、S2合成：以二硫化碳过量溶剂法,将二硫化碳、苛性碱和有机混合胺混合反应和S3二硫化碳回收：将步骤S2中合成后过量的二硫化碳,采用先常压、再减压的方式,分步蒸馏回收。本发明,不需要人工多不混合的繁琐步骤,且避免了混合不均匀的缺陷,不需要高温高压,能耗小且工艺简单可靠,几乎对所有的过渡态重金属都具有螯合沉除作用,相较与单一硫代氨基羧酸盐对飞灰中重金属有更好的稳定化效果。(The invention discloses a synthetic method of a mixed heavy metal capture agent, which comprises the following steps: s1 sampling: taking carbon disulfide, caustic alkali and organic mixed amine for standby, and synthesizing by S2: the carbon disulfide, caustic and organic mixed amine mixed reaction and S3 carbon disulfide recovery are carried out in a carbon disulfide excess solvent process: and (4) distilling and recovering the excessive carbon disulfide synthesized in the step S2 step by step in a mode of firstly carrying out normal pressure and then carrying out reduced pressure. The method does not need complicated manual steps without mixing, avoids the defect of uneven mixing, does not need high temperature and high pressure, has small energy consumption and simple and reliable process, almost has chelation and precipitation effects on all transition-state heavy metals, and has better stabilization effect on heavy metals in fly ash compared with single thiocarbamate.)

1. A synthetic method of a mixed heavy metal capture agent is characterized in that: the method comprises the following steps:

S1: sampling: taking carbon disulfide, caustic alkali and organic mixed amine for standby;

S2: synthesizing: carbon disulfide, caustic alkali and organic mixed amine are mixed and reacted by a carbon disulfide excess solvent method.

2. the method for synthesizing the mixed heavy metal scavenger according to claim 1, wherein the method comprises the following steps: the molar ratio of the organic mixed amine to the caustic alkali to the carbon disulfide is 1: 4-6.

3. the method for synthesizing the mixed heavy metal scavenger according to claim 2, wherein the method comprises the following steps: the organic mixed amine is a plurality of dimethylamine, diethylamine, ethylmethyldiamine, diethylamine, propylethyldiamine and diethylamine.

4. The method for synthesizing the mixed heavy metal scavenger according to claim 3, wherein the method comprises the following steps: the organic mixed amine accounts for 30-50% of the total mass.

5. The method for synthesizing the mixed heavy metal scavenger according to claim 1, wherein the method comprises the following steps: the caustic alkali is in the form of powder, granules or flakes.

6. The method for synthesizing the mixed heavy metal scavenger according to claim 5, wherein the method comprises the following steps: the caustic alkali is sodium hydroxide or potassium hydroxide.

7. the method for synthesizing the mixed heavy metal scavenger according to claim 1, wherein the method comprises the following steps: the synthesis temperature in the step S2 is 0-40 ℃, and the synthesis time is 2-6 h.

8. the method for synthesizing the mixed heavy metal scavenger according to claim 1, wherein the method comprises the following steps: further comprising the steps of:

S3: and (3) recovering carbon disulfide: and (4) distilling and recovering the excessive carbon disulfide synthesized in the step S2 step by step in a mode of firstly carrying out normal pressure and then carrying out reduced pressure.

9. the method for synthesizing the mixed heavy metal scavenger according to claim 8, wherein the method comprises the following steps: the atmospheric distillation temperature in the step S3 is 70-80 ℃.

Technical Field

The invention relates to the technical field of organic mixed amine synthesis, in particular to a synthetic method of a mixed heavy metal capture agent.

Background

municipal solid waste is a complex mixed waste containing considerable amounts of heavy metals. When municipal solid waste is treated by adopting an incineration method, a large amount of volatile elements such as heavy metals of lead, cadmium, zinc, mercury, chromium and the like are volatilized into flue gas due to high temperature and are finally enriched in fly ash. Therefore, the waste incineration fly ash has great harm to the environment and human bodies, and heavy metals in the fly ash need to be stabilized and treated to reach the landfill standard and then concentrated.

The fly ash solidification and stabilization technologies mainly comprise cement solidification, medicament stabilization, asphalt solidification and resin solidification, and a medicament stabilization method can be independently used and has the advantages of small volume-increasing ratio, low energy consumption, simple process and the like, so that the fly ash solidification and stabilization technology is widely used. The molecular structure of the thiocarbamate contains polar groups, so that the thiocarbamate has extremely strong complexing ability with various heavy metals, and has the characteristics of low dosage, high reaction speed, small water solubility of generated chelate and the like, and has very wide application prospect compared with other heavy metal collecting agents.

studies have shown that (Hangon G, Bradshaw D, Ekmekci Z. the Journal of the South African Institute of Mining and metals, 2005,105: 199-206) compared to using a single trapping agent, different mixed group trapping agents have synergistic effects, mainly due to the fact that the synergistic effect between long and short hydrocarbon chains and functional groups is fully utilized to improve the heavy metal stabilization performance and the adsorption characteristics of the mixed trapping agent on the surface of the fly ash condensate are better than those of a single trapping agent.

However, at present, mixed thioamino carboxylates cannot be synthesized using conventional methods, and the mixed thioamino carboxylates in practical use are all prepared by artificially mixing single thioamino carboxylates by mechanical stirring and then using them. But has the defects of uneven mixing, complex operation and the risk of polluting the field environment in the mixing process.

Disclosure of Invention

The present invention aims to provide a method for synthesizing a mixed heavy metal scavenger, so as to solve the problems in the background technology.

In order to achieve the purpose, the invention provides the following technical scheme: a synthetic method of a mixed heavy metal capture agent comprises the following steps:

s1: sampling: taking carbon disulfide, caustic alkali and organic mixed amine for standby;

S2: synthesizing: carbon disulfide, caustic alkali and organic mixed amine are mixed and reacted by a carbon disulfide excess solvent method.

Preferably, the molar ratio of the organic mixed amine to the caustic alkali to the carbon disulfide is 1: 4 to 6.

preferably, the organic mixed amine is a plurality of dimethylamine, diethylamine, ethylmethyldiamine, diethylamine, propylethyldiamine, and diethylamine.

Preferably, the organic mixed amine accounts for 30-50% of the total mass.

Preferably, the caustic is in the form of powder, granules or flakes.

preferably, the caustic is sodium hydroxide or potassium hydroxide.

Preferably, the synthesis temperature in the step S2 is 0-40 ℃, and the synthesis time is 2-6 h.

preferably, the method further comprises the following steps: s3: and (3) recovering carbon disulfide: and (4) distilling and recovering the excessive carbon disulfide synthesized in the step S2 step by step in a mode of firstly carrying out normal pressure and then carrying out reduced pressure.

Preferably, the atmospheric distillation temperature in the step S3 is 70 to 80 ℃.

Compared with the prior art, the invention has the beneficial effects that:

1. The mixed thioamino carboxylate is synthesized by the one-step method, the complicated steps of manual operation and no mixing are not needed, and the defect of uneven mixing is avoided;

2. The preparation method for synthesizing the mixed thioamino carboxylate by the one-step method does not need high temperature and high pressure, has low energy consumption and simple and reliable process;

3. The mixed thioamino carboxylate heavy metal capture agent synthesized by the one-step method has chelation and sedimentation effects on almost all transition-state heavy metals, and has better stabilization effect on heavy metals in fly ash compared with single thioamino carboxylate.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The invention provides a technical scheme that: