CN-118387965-B - Method for purifying brackish water by modifying aerogel

Abstract

The invention relates to the technical field of brackish water treatment, and provides a method for purifying brackish water by modified aerogel, which comprises the steps of adding acid modified aerogel into brackish water and stirring to form a first solid-liquid mixture; the method comprises the steps of carrying out solid-liquid separation on a first solid-liquid mixture to obtain primary purified brackish water, adding alkali modified aerogel into the primary purified brackish water, stirring to form a second solid-liquid mixture, and carrying out solid-liquid separation on the second solid-liquid mixture to finish brackish water purification. The invention utilizes the characteristic of high specific surface area and high void ratio of modified aerogel to adsorb ions in brackish water, firstly, grinding acid modified aerogel into powder; then, the acid modified aerogel powder is put into brackish water to adsorb heavy metal ions such as lead, mercury, arsenic and cadmium and organic matters such as benzene, phenol, ether and naphthalene, and after solid-liquid separation, alkali modified aerogel is added into the brackish water to exchange ions such as sodium, potassium, calcium, magnesium and barium, thereby realizing the removal of ions in the brackish water in a grading way, and the aerogel is separated by suction filtration.

Inventors

• LI KE
• WANG HAO
• DU HONGWEI
• LI HAI
• ZHANG YIFEI

Assignees

• 内蒙古科技大学

Dates

Publication Date

20260505

Application Date

20240527

Claims (3)

1. 1. A method for purifying brackish water by modifying aerogel, comprising: adding acid modified aerogel into brackish water, and stirring to form a first solid-liquid mixture; carrying out solid-liquid separation on the first solid-liquid mixture to obtain primary purified brackish water; adding alkali modified aerogel into the primary purified brackish water to stir to form a second solid-liquid mixture; Performing solid-liquid separation on the second solid-liquid mixture to finish brackish water purification; Adding the acid modified aerogel into the brackish water, stirring and soaking for 30 minutes, wherein the stirring speed is 300rpm; Adding alkali modified aerogel into brackish water, stirring and soaking for 30 minutes, wherein the stirring speed is 300rpm; the acid modified aerogel is a plurality of granular acid modified aerogels with the particle size below 100 meshes; the alkali modified aerogel is a plurality of granular alkali modified aerogels with the particle size below 100 meshes; The acid modified aerogel is prepared by adding hydrochloric acid into sodium silicate for sol-gel, and absorbs heavy metal ions including lead, mercury, arsenic and cadmium and organic matters including benzene, phenol, ether and naphthalene in brackish water; The alkali modified aerogel is prepared by dropwise adding ammonia water into silica gel, and the alkali modified aerogel exchanges sodium, potassium, calcium, magnesium and barium ions in brackish water to realize the hierarchical removal of ions in the brackish water.
2. 2. The method of purifying brackish water by modifying aerogel according to claim 1, wherein the volume ratio of the brackish water to the acid modified aerogel is 1:150-1:250.
3. 3. The method of purifying brackish water by modifying aerogel according to claim 1, wherein the ratio of brackish water to alkali modified aerogel is 1:150-1:250.

Description

Method for purifying brackish water by modifying aerogel Technical Field The invention relates to the technical field of brackish water treatment, in particular to a method for purifying brackish water by modified aerogel. Background Brackish water is mainly distributed in northern and eastern coastal areas. The population of rural bitter drinking water is 3800 tens of thousands. The bitter water is characterized by bitter taste, difficult direct drinking, gastrointestinal dysfunction and low immunity caused by long-term drinking. The existing method for treating brackish water comprises a distillation method, an electrodialysis method and the like, and the electroosmosis method utilizes an ion exchange membrane to separate anions and cations in brine under the action of an electric field, so that the salt concentration in a fresh water chamber is reduced to obtain fresh water, and the electroosmosis method has strict requirements on water quality and needs to pretreat raw water. The distillation method is suitable for laboratory and small-scale brackish water treatment, and large-scale brackish water desalination production cannot be performed. Disclosure of Invention The invention aims to solve at least one technical problem in the background art and provides a method for purifying brackish water by modifying aerogel. To achieve the above object, the present invention provides a method for purifying brackish water by modifying aerogel, comprising: adding acid modified aerogel into brackish water, and stirring to form a first solid-liquid mixture; carrying out solid-liquid separation on the first solid-liquid mixture to obtain primary purified brackish water; adding alkali modified aerogel into the primary purified brackish water to stir to form a second solid-liquid mixture; And (3) carrying out solid-liquid separation on the second solid-liquid mixture to finish the purification of brackish water. According to one aspect of the invention, the acid-modified aerogel is a number of particulate acid-modified aerogels having a particle size of 100 mesh or less. According to one aspect of the invention, the volume ratio of the brackish water to the acid modified aerogel is 1:150-1:250. According to one aspect of the invention, the acid-modified aerogel is added to the brackish water and then stirred for 10-60 minutes at a stirring speed of 180-600rpm. According to one aspect of the invention, the acid-modified aerogel is added to the brackish water and stirred for 30 minutes at a stirring speed of 300rpm. According to one aspect of the invention, the alkali-modified aerogel is a number of particulate alkali-modified aerogels having a particle size of 100 mesh or less. According to one aspect of the invention, the ratio of the brackish water to the alkali modified aerogel is from 1:150 to 1:250. According to one aspect of the invention, the alkali modified aerogel is added to the brackish water and then stirred for 10-60 minutes at a stirring speed of 180-600rpm. According to one aspect of the invention, the alkali modified aerogel is added to the brackish water and stirred for 30 minutes at a stirring speed of 300rpm. According to the scheme of the invention, the method for adsorbing ions in brackish water utilizes the characteristics of high specific surface area and high void ratio of the modified aerogel, firstly, the acid modified aerogel is ground into powder, then the acid modified aerogel powder is put into the brackish water to adsorb heavy metal ions such as lead, mercury, arsenic, cadmium and the like and organic matters such as benzene, phenol, ether, naphthalene and the like, after solid-liquid separation, alkali modified aerogel is added into the brackish water to exchange ions such as sodium, potassium, calcium, magnesium and barium, and the like, so that the ions in the brackish water are removed in a grading manner, and the aerogel is separated by suction filtration. According to the scheme of the invention, the method for adsorbing calcium, magnesium, barium, lead, mercury, arsenic, sulfate radical, chloride radical and other ions and organic matters in the brackish water by utilizing different modified aerogels can select alkali modified silica aerogel with ion exchange function for cations such as calcium, magnesium, barium and the like, and can select acid modified silica aerogel with anion functional groups with adsorption function for anions such as lead, mercury, arsenic, sulfate radical, chloride radical and the like. According to the scheme, the problem of high-value utilization of heavy metal solidification can be solved, and the efficient utilization of brackish water resource purification can be realized. Drawings Fig. 1 schematically shows a flow chart of a method for purifying brackish water by modifying aerogel according to one embodiment of the present invention. Detailed Description The present disclosure will now be discussed with reference to exemplary embodiments. It should