Material and its method for rapid eluting in an ionic rare earth ore leaching site

Abstract

The invention relates to a material and its method for rapidly eluting ammonium ions and soluble metal cations in an ionic rare earth ore leaching site, which comprises the following steps: 1) Ferrous sulfate is dissolved in water as an eluant; 2) Take the soil sample from the closed leaching site of ionic rare earth ore to make an eluting column, use the above-mentioned eluent to elute, more than 95% water-soluble and exchangeable ammonium ions in the soil sample are eluted, while more than 90% of the residual rare earths in the soil sample are exchanged into the eluent, which can quickly achieve the purpose of eluting ammonium ions in the leaching site and recovering the residual rare earths, and is beneficial to the soil remediation for the leaching site.

Claims

1. A method for eluting an ionic rare earth ore leaching site, comprising: weighing ferrous sulfate (FeSO.sub.4.7H.sub.2O) and dissolve the weighted ferrous sulfate in water to prepare a solution with a concentration in a range from 0.5 g/L to 5 g/L, and using one of sulfuric acid and alkali to adjust a PH value of the solution to be in a range from 4 to 6 to obtain an eluant; and taking a soil sample from the ionic rare earth ore leaching site in Jiangxi to make an eluting column, and using the eluent to elute the eluting column according to a ratio of the eluant (ml)/the soil sample (g) being in a range from 1 to 5 to obtain an eluted sample; taking the eluted sample at determined intervals to analyze contents of ammonia nitrogen and rare earths thereof; after the eluting is completed, re-taking the eluted sample to analyze contents of ammonia nitrogen and rare earths in the soil sample in the eluting column.

2. The method for eluting the ionic rare earth ore leaching site according to claim 1, wherein a raw material of the ferrous sulfate (FeSO.sub.4.7H.sub.2O) is industrial waste ferrous sulfate from titanium dioxide industry.

3. The method for eluting the ionic rare earth ore leaching site according to claim 1, wherein the concentration of the solution is 3 g/L, and the PH value of the solution is 5.5.

4. The method for eluting the ionic rare earth ore leaching site according to claim 1, wherein the ratio of the eluant (ml)/the soil sample (g) is 4.

5. The method for eluting the ionic rare earth ore leaching site according to claim 1, more than 95% water-soluble and exchangeable ammonium ions in the soil sample in the ionic rare earth ore leaching site are eluted, more than 90% of rare earths in the soil sample are exchanged in to the eluent.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a schematic diagram of the technical route for the method of rapid eluting in an ionic rare earth ore leaching site.

DETAILED DESCRIPTION OF THE INVENTION

(2) The following is a further detailed description in combination with the preferred embodiments shown in the drawings; specific embodiments are as follows:

Embodiment 1

(3) Weigh 6 g of ferrous sulfate (FeSO4.7H2O) and dissolve it in 2 L of deionized water to obtain the eluant of pH=5.5; take a soil sample of a closed ore rare earth ore leaching site in southern Jiangxi (sampling depth is 3-5 meters). After testing, the total content of ammonia nitrogen (NH3-N) in this soil sample is 286 mg/kg, the water-soluble and exchangeable ammonia nitrogen is 268 mg/kg, the fixed ammonia nitrogen is 18 mg/kg, and the content of rare earth (ΣRE) is 85 mg/kg; take 300 g of soil sample to make an exchange column, elute the exchange column with the above eluant, collect the eluent and analyze the content of ammonium ions and rare earths in the eluent. When the eluent is collected to 1,200 ml, the ammonia nitrogen and rare earths in the eluent are less than 1 mg/L, indicating that the eluting has been completed; after removing the soil sample from the eluting column and drying it, the content of ammonia nitrogen and rare earth (IRE) were analyzed to be 23 mg/kg and 4.3 mg/kg, respectively. The elution rate of water-soluble and exchangeable ammonia nitrogen was 98.1%, and the elution rate of residual rare earths was 94.9%.

Embodiment 2

(4) Weigh 4 g of industrial grade ferrous sulfate (FeSO4.7H2O) and dissolve it in 2 L of running water to obtain the eluant of pH=5.5; take 300 g of soil sample in Embodiment 1 to make an exchange column, elute the exchange column with the new eluent, collect the eluent and analyze the content of ammonium ions and rare earths in the eluent. When the eluent is collected to 1,200 ml, the ammonia nitrogen and rare earths in the eluent are less than 1 mg/L, indicating that the eluting has been completed; after removing the soil sample from the eluting column and drying it, the content of ammonia nitrogen and rare earth (IRE) were analyzed to be 28 mg/kg and 5.5 mg/kg, respectively. The elution rate of water-soluble and exchangeable ammonia nitrogen was 96.3%, and the elution rate of residual rare earths was 93.5%.