Method for treating acid uranium-bearing wastewater by utilizing modified chitosan adsorbents

Abstract

The invention provides a method for treating acid uranium-bearing wastewater by utilizing modified chitosan adsorbents. Aimed at problems of complicated process, high operation cost and raw material cost and the like of uranium-bearing wastewater treatment in the uranium ore metallurgy process, the modified chitosan adsorbents are utilized for treating the acid uranium-bearing wastewater. The modified chitosan adsorbents include one or more of triethylene tetramine, ethidene diamine, diethylene triamine or tetraethylene pentamine modified chitosan adsorbents. The research shows that the modified chitosan adsorbents have good absorption effects on uranium and a high removing rate for uranium in low-concentration uranium-bearing wastewater, and the removing rate is larger than 95%.

Description

technical field

[0001] The invention relates to a technology for adsorbing uranium in acidic uranium-containing wastewater, in particular to a method for treating acidic uranium-containing wastewater by using a modified chitosan adsorbent. Background technique

[0002] Biosorption of heavy metals is an emerging research field. In the past ten years, great progress has been made in the research of biosorption of heavy metals. A large number of studies have shown that some microorganisms such as bacteria, fungi, algae and biopolymers have strong Strong adsorption capacity. Biosorption refers to the adsorption of heavy metal ions by biological materials through a series of biochemical actions, including complexation, chelation, ion exchange, transformation, absorption, and inorganic microprecipitation. Compared with other similar technologies (such as chemical precipitation, activated carbon adsorption, ion exchange, electrodialysis, etc.) as a new technology to recover heavy ...

Examples

Embodiment 1

[0016] Select 50ml of uranium-containing wastewater solution with a concentration of 63.0mg / L (if there is organic matter in the wastewater, remove the organic matter in the solution first to avoid interfering with the adsorption of the adsorbent or the concentration test), adjust the pH to 4-5, add to 200mg CATT In a Erlenmeyer flask, the shaker was adsorbed for 72 hours, and the concentration of uranium in the solution before and after adsorption was measured. The calculated adsorption capacity of the adsorbent CATT for uranium is 15.1 mg / g (dry), and the removal rate of uranium in the solution is 95.9%.

[0017] 2mol / L HCl was chosen as the desorbent for chitosan-based adsorbent CATT uranium. The adsorbent CATT saturated with uranium was desorbed by 2mol / L HCl, and the desorption rate was 97%.

[0018] The effect of solution pH on the adsorption performance of CATT uranium, such as figure 1 shown. The adsorbent CATT has a high adsorption capacity in the pH range of 3~6, ...

Embodiment 2

[0020] Select 50ml of uranium-containing wastewater solution with a concentration of 35.0mg / L (if there is organic matter in the wastewater, remove the organic matter in the solution first to avoid interfering with the adsorption of the adsorbent or the concentration test), adjust the pH to 4-5, add to 200mg CATT In a Erlenmeyer flask, the shaker was adsorbed for 72 hours, and the concentration of uranium in the solution before and after adsorption was measured. After calculation, the adsorption capacity of the adsorbent CATT for uranium is 8.6 mg / g (dry), and the removal rate of uranium in the solution is 98.3%.

Embodiment 3

[0022] Select 50ml of uranium-containing wastewater solution with a concentration of 6.26mg / L (if there is organic matter in the wastewater, remove the organic matter in the solution first to avoid interfering with the adsorption of the adsorbent or the concentration test), adjust the pH to 4-5, and add to 200mg CATT In a Erlenmeyer flask, the shaker was adsorbed for 72 hours, and the concentration of uranium in the solution before and after adsorption was measured. After calculation, the adsorption capacity of the adsorbent CATT for uranium is 1.5 mg / g (dry), and the removal rate of uranium in the solution is 95.8%.

technical field

[0001] The invention relates to a technology for adsorbing uranium in acidic uranium-containing wastewater, in particular to a method for treating acidic uranium-containing wastewater by using a modified chitosan adsorbent. Background technique

[0002] Biosorption of heavy metals is an emerging research field. In the past ten years, great progress has been made in the research of biosorption of heavy metals. A large number of studies have shown that some microorganisms such as bacteria, fungi, algae and biopolymers have strong Strong adsorption capacity. Biosorption refers to the adsorption of heavy metal ions by biological materials through a series of biochemical actions, including complexation, chelation, ion exchange, transformation, absorption, and inorganic microprecipitation. Compared with other similar technologies (such as chemical precipitation, activated carbon adsorption, ion exchange, electrodialysis, etc.) as a new technology to recover heavy ...

Examples

Embodiment 1

[0016] Select 50ml of uranium-containing wastewater solution with a concentration of 63.0mg / L (if there is organic matter in the wastewater, remove the organic matter in the solution first to avoid interfering with the adsorption of the adsorbent or the concentration test), adjust the pH to 4-5, add to 200mg CATT In a Erlenmeyer flask, the shaker was adsorbed for 72 hours, and the concentration of uranium in the solution before and after adsorption was measured. The calculated adsorption capacity of the adsorbent CATT for uranium is 15.1 mg / g (dry), and the removal rate of uranium in the solution is 95.9%.

[0017] 2mol / L HCl was chosen as the desorbent for chitosan-based adsorbent CATT uranium. The adsorbent CATT saturated with uranium was desorbed by 2mol / L HCl, and the desorption rate was 97%.

[0018] The effect of solution pH on the adsorption performance of CATT uranium, such as figure 1 shown. The adsorbent CATT has a high adsorption capacity in the pH range of 3~6, ...

Embodiment 2

[0020] Select 50ml of uranium-containing wastewater solution with a concentration of 35.0mg / L (if there is organic matter in the wastewater, remove the organic matter in the solution first to avoid interfering with the adsorption of the adsorbent or the concentration test), adjust the pH to 4-5, add to 200mg CATT In a Erlenmeyer flask, the shaker was adsorbed for 72 hours, and the concentration of uranium in the solution before and after adsorption was measured. After calculation, the adsorption capacity of the adsorbent CATT for uranium is 8.6 mg / g (dry), and the removal rate of uranium in the solution is 98.3%.

Embodiment 3

[0022] Select 50ml of uranium-containing wastewater solution with a concentration of 6.26mg / L (if there is organic matter in the wastewater, remove the organic matter in the solution first to avoid interfering with the adsorption of the adsorbent or the concentration test), adjust the pH to 4-5, and add to 200mg CATT In a Erlenmeyer flask, the shaker was adsorbed for 72 hours, and the concentration of uranium in the solution before and after adsorption was measured. After calculation, the adsorption capacity of the adsorbent CATT for uranium is 1.5 mg / g (dry), and the removal rate of uranium in the solution is 95.8%.

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