JPS6046920A - Separation of lithium from water associated with natural gas - Google Patents

Abstract

PURPOSE:To recover lithium from water associated with natural gas, in high efficiency, by attaching magnesium to amorphous hydrated aluminum oxide, and using the product as an adsorbent. CONSTITUTION:Sodium aluminate is dissolved in an aqueous solution of sodium hydroxide, an oxidizing agent is added to the solution, carbon dioxide gas is introduced into the solution at about 5 deg.C, and the precipitate produced by hydrolysis is separated by filtration and is washed and dried to obtain amorphous hydrated aluminum oxide. The aluminum oxide is dispersed in an aqueous solution of magnesium sulfate and stirred, and the solid component attached with magnesium is separated and used as an adsorbent. The adsorbent has an Al content of about 27-28%, Mg content of about 2.2-2.6%, water-content of about 44-45%, and Mg/Al ratio of about 0.08-0.1.

Description

DETAILED DESCRIPTION OF THE INVENTION Lithium salts have traditionally been used in heat-resistant ceramics, hard glass grease, air conditioning refrigerants, and the like, and the amount required is increasing year by year. Furthermore, as the development of welded a-fired furnaces and lithium batteries progresses, the demand for lithium is expected to increase rapidly, and dissolved lithium resources fM have recently attracted attention. Methods for extracting lithium from seawater and geothermal water have been studied and have been studied.

On the other hand, water associated with natural gas contains approximately 1.0% lithium. h6.0g/
Since the concentration is considerably higher than that in seawater, it is considered to be advantageous in its collection.

could hardly be applied. In this case, interference by silicon is naturally considered, so even if silicon was removed as a precaution, only one result was obtained.

So, we conducted various preliminary experiments to find out what was causing this, and found that 5. The concentration of coexisting magnesium was greatly affected.

This invention focused on this point, and conducted an adsorption experiment using an adsorbent whose main component is hydrated aluminum oxide to which magnesium had been attached (hereinafter abbreviated as Mg-attached adsorbent). Compared to adsorbents whose main component is amorphous hydrated aluminum oxide (hereinafter abbreviated as Mg-free adsorbents), the adsorption rate is significantly increased. ■ The shadow of coexisting silicon is extremely small. ■ The influence of PH is also small. This is based on the results of discovering the following advantages.

Regarding the preparation method of the adsorbent used this time, first, an Mg-free adsorbent was prepared. The method for preparing it is to add P.
The carbon dioxide original gas is agitated and hydrolyzed until the ll value decreases to 9.5. The precipitate produced by the hydrolysis was filtered and washed with cold water, and dried under reduced pressure at room temperature of about 2,500°C. The analysis was carried out by 1@yaku ray diffraction of hydrated aluminum without legs.

Next, as for the preparation method of the Mg layered adsorbent, 100 parts of a 0.05 mol Il + ij acid magnesium solution (pH about 7.0) was added to 0.1 part of the above Mg-free adsorbent under reduced pressure. The precipitate was added with magnesium for 5 minutes while changing the stirring time, and the precipitate was washed twice with 25 parts of water by centrifugation. 14 Mg adhesion grade adhesive 0 parts and natural gas associated water 1 part
After adding 00 parts of lithium and carrying out lithium absorption layer for 24 hours, the remaining lithium concentration of the filtrate after filtering off the adsorbent was determined by optical analysis and the amount of lithium adsorbed was calculated. Figure 1 shows the relationship between magnesium adhesion time and lithium adsorption amount. As a result, the magnesium deposition time was set at 48 hours.

The composition of the Mg-attached adsorbent obtained under these conditions after vacuum G-shielding is 27.0 to 28.0% aluminum-containing 6'M.
, magnesium content 2.2-2.6%, moisture content M
44. O~4? i, 0%, composition ratio Mg/AI 0.
08-0.10 and 7hi.

Adsorption experiments were conducted on simulated seawater and actual samples using the Mg-free adsorbent and Mg-attached adsorbent obtained above, and comparative tests were conducted on the adsorption rate, the influence of silica, the influence of PH, and the adsorption isotherm. Gyo Natsu/ζ.

As a result, as shown above, there was a significant difference between the two, and it was found that the Mg-attached adsorbent was extremely effective in extracting lithium from water associated with natural gas. It is believed that the lithium extraction method according to the present invention is effective for l+i5 not only for water associated with natural gas but also for lithium resources such as seawater and geothermal water.

Next, examples of this invention will be shown.

Example 1 Adding 1 part of Mg-free skin to 100 parts of simulated Tiσ water or 0.1 part of Mg-layered adsorbent to 100 parts of gas-associated water,
The composition (analytical values) of the chamber is shown in the table below.

Figure 2 shows several layer times and lithium absorption 7r'! Shows the relationship between quantities. As is clear here, in the case of the Mg-free adsorbent, simulated seawater is used as the target sample, but it still takes about 120 hours to reach an apparent adsorption equilibrium, whereas in the case of the Mg-attached adsorbent, the target sample is simulated seawater. However, in the case of an agent that can achieve adsorption equilibrium in about 6 hours and significantly increase the adsorption rate, by changing the amount of lithium added to the above-mentioned celestial gas water (lithium concentration 1.
In the case of 2 mg/I, the procedure was repeated in the same manner as in Example 1 above (with some of the lithium removed).

On the other hand, in the case of Mg-free water, the above-mentioned test sample 1 was compared with a sample in which the silica of the water associated with natural gas was previously removed with Mg-free water.
The same procedure was carried out for 11j water by changing the amount of lithium added.

As a result, the slope of the straight line part of the adsorption isotherm of the Mg adsorbent in the simulated τIσ water is approximately 1 and 7ζ. The isoirni line of the adhered adsorbent was obtained in the form of a curved line, albeit somewhat vaguely.

Furthermore, the amount of lithium adsorbed by the adsorbent adsorbed with Mg against water associated with natural gas containing 14 degrees 3 and 75 mg/l of lithium is 6.08 mg/g, whereas the amount of lithium adsorbed by the adsorbent without Mg is almost 6.08 mg/g. For natural gas-associated water that was not shown or had silicon removed in advance, lithium adsorption from one company was 0.36 mg/g. Thus, a large difference in adsorption amount was confirmed between the two.

Example 3 Silicon was added stepwise at different concentrations, and Pl (7.9
Simulated seawater 1 with a lithium concentration of 1.5 mg/I adjusted to
To 00 parts, 1 part of the adhesion layer agent with Mg or 0.11 parts of the Mg non-intake agent was added, and adsorption was carried out with stirring for 24 hours.
The following operations were performed in the same manner as in Example 1 above, and the relationship between silicon concentration and lithium absorption amount as shown in FIG. 4 was determined.

As a result, in the case of Mg-free adsorbent, it is significantly affected by coexisting silicon, and when the silicon concentration is 'tOmg/l,
Only about 5% of the amount of lithium adsorbed when they were not present together was adsorbed. On the other hand, the amount of lithium adsorbed by the adsorbent adsorbing magnesium decreased by only about 4% even when 213 mg/I of silicon coexisted.

Figure 5 shows the relationship between pH and lithium absorption amount. In this case, the room temperature is about 25°C, and the adsorption time is 24°C.
To adjust the pH, use hydrochloric acid and aqueous ammonia.
there was. Compared to the above-mentioned natural gas with adjusted PR, one advantage is that there is less influence of pH.

Example 5 Analysis of alkali and alkaline earth metals in the adsorbent after the Sufuo test was carried out.

100 parts of natural gas-associated water (PH 7,90) was added to 0.1 part of the Mg adhesion absorbent, and an adsorption experiment was conducted for 24 hours.

After removing the adsorbent by filtration, it was washed twice with 5 parts of pure water and subjected to absorption analysis on the diluted solution dissolved in specified hydrochloric acid. As a result, sodium sail 77 n+g/g potassium 0.28mg/g, calcium 1-Omg/g
, magnesium 9.8 mg/g.

Example 6 The adsorbed lithium was desorbed and recovered.

For desorption, the same adsorption experiment procedure as in Example 5 was repeated 6 times, and 30 parts of water was added to 5 parts of the lithium adsorbent obtained after washing and drying.
Boiled for 6 hours 1□j! ! I went by doing.

The precipitate of 1; modified lit was removed by filtration while hot. When 75 parts of sodium chloride is further added to 15 parts of this filter 11 and heated, lithium carbonate will precipitate.
We were able to recover 100% of lithium carbonate.

[Brief explanation of the drawing]

FIG. 1 is a graph showing the relationship between magnesium adhesion time and lithium adsorption amount. Figure 2 shows the relationship between adsorption time and lithium adsorption amount (○-Mg
layered adsorbent, 8-Mg non-adsorbent). Figure 3 is an adsorption isotherm diagram of Mg-adhered adsorbent and Mg-free adsorbent (〇-adsorbent with adhesion, 8-Mg-free adsorbent (simulated seawater),
Raw Mg-free adsorbent (water associated with silicon removal)). Figure 4 is a relationship curve diagram between silicon concentration and lithium number layer amount (○
, △ signs are the same as in Fig. 2). Applicant: Miyazaki Prefecture Chiφ Yutaka Matsugata Agent: Miyazaki Prefectural Industrial Research Institute Director Toshi Noboru Figure 4 Silicon concentration (+ng/l)

Claims (1)

[Claims] Composition ratio Mg/
A method for collecting lithium from natural gas-associated water using an adsorbent whose main component is hydrated aluminum oxide to which magnesium is attached with an Al content of 08 to 0.10.