Method for stabilizing heavy metal and antibiotic by coupling slow mineralization of calcium phosphate liquid precursor with continuous flow

Patent metadata

Field	Value
Publication number	US-12338141-B2
Application number	US-202418733953-A
Country	US
Kind code	B2
Filing date	Jun 5, 2024
Priority date	Aug 3, 2023
Publication date	Jun 24, 2025
Grant date	Jun 24, 2025

Abstract

A method for stabilizing heavy metals and antibiotics by coupling slow mineralization of a calcium phosphate liquid precursor with a continuous flow of contaminants is provided. In the method, a mixed solution containing a calcium salt, a phosphate, collagen and a polymer is pumped into a packed column with a wet packing method. To-be-treated sewage is pumped into the packed column, and heavy metals and antibiotics in the to-be-treated sewage are solidified and removed during mineralization of calcium phosphate.

First claim

What is claimed is:

1. A method for stabilizing heavy metals and antibiotics in a continuous flow of to-be-treated sewage through mineralization of calcium phosphate, the method comprising:
generating a calcium salt stock solution and a phosphate stock solution by dissolving a calcium salt and a phosphate in Tris buffers respectively;
adding a polymer into the calcium salt stock solution to obtain a mineralizing solution;
immersing collagen into the mineralizing solution and performing ultrasonic treatment, and then adding the phosphate stock solution to adjust a final concentration ratio of the calcium salt and the phosphate to be greater than or equal to 1.67, thereby obtaining a mixed solution as an initial mineralizing solution;
pumping the initial mineralizing solution into a packed column, wherein a tail of the packed column is provided with a semi-permeable membrane impermeable to the polymer and minerals; and
pumping the to-be-treated sewage into the packed column, and solidifying and removing heavy metals and antibiotics in the to-be-treated sewage during mineralization of calcium phosphate.

2. The method as claimed in claim 1 , wherein the calcium salt is one or more selected from CaCl 2 , Ca(NO 3 ) 2 and CaSO 4 , and the phosphate is K 2 HPO 4 .

3. The method as claimed in claim 1 , wherein a concentration of the calcium salt in the mixed solution is 5 mM-10 mM, and a concentration of the phosphate in the mixed solution is 2 mM-6 mM.

4. The method as claimed in claim 1 , wherein the polymer is one or more selected from polyacrylic acid, polyglutamic acid, and polyaspartic acid.

5. The method as claimed in claim 1 , wherein a concentration of the collagen in the mixed solution is 0.1 g/L-20 g/L.

6. The method as claimed in claim 1 , wherein the semi-permeable membrane is provided at a water outlet of the packed column, and the semi-permeable membrane is configured to allow water molecules and ions to penetrate through.

7. The method as claimed in claim 1 , wherein the packed column is filled with an auxiliary material prior to pumping the initial mineralizing solution into a packed column, and the auxiliary material is one or more selected from quartz sand, zeolite, ceramsite, and activated carbon.

8. The method as claimed in claim 7 , wherein a porosity of the packed column is 30%-75%, and a packing density of the auxiliary material in the packed column is 1.2 g/cm3-3.2 g/cm3.

9. The method as claimed in claim 1 , wherein a flow rate of the to-be-treated sewage in the packed column is 0.15 mL/min-0.9 mL/min.

Assignees

• Univ Tongji

Inventors

• Ling Lan
• Qiao Xin

Classifications

• B01J20/048

  containing phosphorus, e.g. phosphates, apatites, hydroxyapatites · CPC title

• B01J20/28052

  Several layers of identical or different sorbents stacked in a housing, e.g. in a column · CPC title

• C02F1/5236

  using inorganic agents · CPC title

• B01J20/16

  Alumino-silicates (B01J20/12 takes precedence) · CPC title

• B01J20/20

  comprising free carbon; comprising carbon obtained by carbonising processes · CPC title