Fly ash chelating agent and preparation method thereof

Abstract

The invention provides a fly ash chelating agent and a preparation method thereof. The fly ash chelating agent is prepared from the following components in percentage by weight: 5 percent to 8 percent of 0, 0-diisopropyl ammonium dithiophosphate, 3 percent to 7 percent of 2, 3-dithiosuccinic acid, 10 percent to 20 percent of 3-chloro-2-hydroxypropyl trimethyl ammonium chloride, 2 percent to 4 percent of sodium trimethyldithiocarbamate, 3 percent to 7 percent of calcium polysulfide, 0.3 percent to 0.7 percent of an additive and 60 percent to 70 percent of water. The preparation method of the fly ash chelating agent comprises the following steps: adding 0, 0-diisopropyl ammonium dithiophosphate, 2, 3-dithiosuccinic acid, 3-chloro-2-hydroxypropyl trimethyl ammonium chloride, sodium trimethyldithiocarbamate and calcium polysulfide into water, stirring to obtain a mixed solution, adding the additive, and stirring to obtain the fly ash chelating agent. The preparation method of the chelating agent is very simple, and the chelating agent is an organic sulfur compound chelating agent and has the advantages of large molecular weight, strong flocculation function and strong heavy metal chelating capability; the additive of the chelating agent is polyaluminum chloride, so that the chelating capacity of the chelating agent is improved, the toxicity of the heavy metal chelating agent is reduced, and the product and the preparation process are environment-friendly, safe and non-toxic.

Description

technical field [0001] The invention relates to the technical field of designing chelating agents, specifically a liquid compounding chelating agent used for hazardous waste landfill standards and a preparation method thereof. Background technique [0002] While waste incineration realizes the reduction of domestic waste, it also produces fly ash. Domestic waste incineration fly ash has complex components, and the main pollutants are heavy metals with high leaching toxicity, which have serious harm to the environment. After testing, the fly ash of domestic waste incineration contains heavy metals with high leaching concentration, such as Pb, Cr, Cd, Cu, Hg and Zn. At present, there are mainly three mainstream technical methods for processing fly ash in the domestic waste incineration industry. One is to use cement solidification technology to solidify heavy metals. Heavy metals react with cement through ion exchange, passivation, adsorption, chemical adsorption, sedimentati...

AI Technical Summary

Problems solved by technology

At present, there are mainly three mainstream technical methods for processing fly ash in the domestic waste incineration industry. One is to use cement solidification technology to solidify heavy metals. Heavy metals react with cement through ion exchange, passivation, adsorption, chemical adsorption, sedimentation and hydration. Finally, relatively stable compounds such as hydroxides or complexes are formed on the surface of the hydrated silicate colloid C-H-S of cement, but this method has weak integration ability, poor stability, and adaptability to different types of fly ash It is not strong, the capacity of fly ash is large, and the volume of landfill is increased; the second is the melting and solidification method, which is currently recognized as the safest and most stable incineration fly ash stabilization and solidification technology. Fly ash and glass powder are mixed and granulated, and melted at a high temperature of 1000-1400 °C for a period of time, but this method has the disadvantage of high energy consumption; the third is the chemical reagent stabilization method. The core of the conversion of ions into low-solubility, low-mobility polymer complexes or inorganic minerals lies in the selection of chemical integrators, especially the selectivity of chemical reagents to the main polluting heavy metal ions, and the stability of the resulting complexes. property, especially to the leaching property of acidic solution; and the chelating agent used in the sampling chemical reagent stabilization method in the related art is mostly DTC chelating agent (dithiocarbamate is called for short DTC), belongs to non-macromolecule compound, unit The molecular weight contains few complex centers, and the complexes generated with heavy metals can leach high concentration

Images