Method for eluting and restoring 1,2,4-trichlorobenzene polluted soil by cyclodextrin solution

Abstract

The invention discloses a method for eluting and restoring 1,2,4-trichlorobenzene polluted soil by a cyclodextrin solution, which relates to a restoring method of soil organic pollution. The method comprises the following steps: (1) dissolving cyclodextrin in distilled water to prepare a cyclodextrin solution of 1.5-20g/L; (2) polluting a fresh soil sample by a 1,2,4-trichlorobenzene acetone solution to obtain a simulative polluted soil sample with a pollution load of 465.63mg/kg; (3) weighting and uniformly adding the simulative polluted soil sample into an organic glass column, adding quartzsand of 3-5 cm and a little glass wool on the lower part of the column, adding the polluted soil sample and then adding quartz sand of 1-1.5 cm and a little glass wool on the polluted soil sample; eluting the organic glass column with the soil from above down by the cyclodextrin solution; (4) adding active carbon in a container, then adding the cyclodextrin solution containing 1,2,4-trichlorobenzene after eluting, shaking the container for 24h by a shaking table, and then purifying the cyclodextrin solution through a filter with a glass fiber film for standby. The removal rate of the 1,2,4-trichlorobenzene in soil can reach 52-78 percent.

Description

technical field [0001] The invention relates to a method for remediating soil organic matter pollution, in particular to a method for remediating soil 1,2,4-trichlorobenzene pollution by using a natural surfactant as a leaching agent without secondary pollution. Background technique [0002] In view of the seriousness and harmfulness of soil pollution, developed countries have formulated contaminated soil remediation plans since the 1980s, and my country's soil pollution remediation has also received extensive attention in recent years. At present, there are many methods for the remediation of contaminated soil. Among them, the soil leaching method is widely used in the remediation of severely polluted soil. It is a remediation technology that removes organic and inorganic pollutants in the soil by injecting and pumping eluent. It is mainly used to treat chemical adsorption in the pores of soil particles and It is an efficient and permanent in-situ repair technology. The r...

AI Technical Summary

Problems solved by technology

After searching the existing documents, it was found that Chinese Patent Publication No. CN 1570021A, published on January 26, 2005, with the patent name "Repair Method for Surfactant-Enhanced Adsorption and Fixation of Organic Pollution of Soil", mentioned in the patent that firstly use cationic Surfactants adsorb and fix organic pollutants and then use non-ionic surfactants to elute and restore them. However, because cationic surfactants can strongly adsorb on soil particles, it is easy to cause secondary pollution when applied to soil remediation.

Chinese Patent Publication No. CN 101181716A, published on May 21, 2008, the title of the patent is "A Method for Synergistically Remediating Soil Nitrobenzene Pollution with Anion-Nonionic Mixed Surfactants". The technical elements such as the optimal ratio of pollution, effective concentration, and usage amount, as well as the method of synergistically repairing soil nitrobenzene pollution with anion-nonionic mixed surfactants, but due to the toxicity of organic surfactants to plants and soil microorganisms, etc. , secondary pollution may occur after remediation of contaminated soil, and at the same time there is no recycling of the eluent, resulting in waste of resources

The Chinese patent number is CN 101170732A, the publication date was May 7, 2008, and the title of the patent is "Method for treating leaching waste water from soil polluted by benzene series compounds". The soil leaching wastewater of organic matter can be treated efficiently and harmlessly on site, but the report on the green composite leaching and remediation technology of high-concentration toxic organic pollution sites in the patent is ominous

There are few studies on the adsorption behavior of natural surfactants (such as cyclodextrin, etc.) on soil and sediments and their effects on the adsorption of coexisting organic matter. Trichlorobenzene pollution method has not been reported yet