Method for manufacturing carbonate
09643858 ยท 2017-05-09
Assignee
Inventors
Cpc classification
C01F5/22
CHEMISTRY; METALLURGY
C01P2002/72
CHEMISTRY; METALLURGY
International classification
C01F5/22
CHEMISTRY; METALLURGY
Abstract
Methods are disclosed for manufacturing magnesium carbonate and calcium carbonate, specifically manufacturing refined carbonates such as magnesium carbonate (MgCO.sub.3) and calcium carbonate (CaCO.sub.3) through processes including electrolysis, carbon dioxide injection, and calcium oxide (CaO) or calcium hydroxide (Ca(OH).sub.2) injection in seawater.
Claims
1. A method for manufacturing carbonate, comprising: adding calcium oxide (CaO) to sea water solution to produce magnesium hydroxide (Mg(OH).sub.2); performing a first separation of the sea water solution to a supernatant portion, and a lower portion liquid, wherein the lower portion liquid comprises magnesium hydroxide (Mg(OH).sub.2); producing magnesium carbonate by adding carbon dioxide (CO.sub.2) to the lower portion liquid; electrolyzing the sodium chloride (NaCl) contained in the supernatant portion to produce sodium hydroxide (NaOH) and hydrogen chloride (HCl); adding sodium hydroxide (NaOH) obtained from the electrolyzing step into the supernatant portion to produce calcium hydroxide (Ca(OH).sub.2); performing a second separation of the supernatant portion to an upper portion liquid and a second lower portion liquid, the second lower portion liquid comprising calcium hydroxide (Ca(OH).sub.2); and adding carbon dioxide (CO.sub.2) to the second lower portion liquid to produce calcium carbonate (CaCO.sub.3).
2. The method of claim 1, further comprising electrolyzing sodium chloride (NaCl) contained in the upper portion liquid to produce sodium hydroxide (NaOH) and hydrogen chloride (HCl).
3. The method of claim 2, further comprising adding carbon dioxide (CO.sub.2) to sodium hydroxide (NaOH) obtained from the upper portion liquid to produce sodium carbonate (Na.sub.2CO.sub.3).
4. The method of claim 2, wherein the sodium hydroxide (NaOH) concentration in the upper portion liquid ranges from 3 weight percent to 50 weight percent.
5. The method of claim 1, further comprising extracting sodium chloride (NaCl) from the upper portion liquid.
6. The method of claim 5, wherein the extracting of sodium chloride is performed by reverse osmosis.
7. The method of claim 5, wherein the extracting of sodium chloride is performed by ion exchange.
8. The method of claim 1, wherein adding calcium oxide (CaO) to the sea water solution comprises adding calcium oxide to bring a concentration of calcium oxide within the sea water solution to between 0.29 weight percent and 0.31 weight percent.
9. The method of claim 1, wherein producing magnesium carbonate comprises using a process temperature ranging from 10 degrees Celsius to 90 degrees Celsius.
10. The method of claim 9, wherein producing magnesium carbonate comprises using a reaction time ranging from about two hours to about five hours.
11. A method for manufacturing carbonate, comprising: adding calcium hydroxide (Ca(OH).sub.2) to sea water solution to produce magnesium hydroxide (Mg(OH).sub.2); performing a first separation of the sea water solution to a supernatant portion, and a lower portion liquid, wherein the lower portion liquid comprises magnesium hydroxide (Mg(OH).sub.2); producing magnesium carbonate by adding carbon dioxide (CO.sub.2) to the lower portion liquid; electrolyzing the sodium chloride (NaCl) contained in the supernatant portion to produce sodium hydroxide (NaOH) and hydrogen chloride (HCl); adding calcium chloride (CaCl.sub.2) to the supernatant portion and electrolyzing the CaCl.sub.2 to produce calcium hydroxide (Ca(OH).sub.2); performing a second separation of the supernatant portion to an upper portion liquid and a second lower portion liquid, the second lower portion liquid comprising calcium hydroxide (Ca(OH).sub.2); and adding carbon dioxide (CO.sub.2) to the second lower portion liquid to produce calcium carbonate (CaCO.sub.3).
12. The method of claim 11, further comprising electrolyzing sodium chloride (NaCl) contained in the upper portion liquid to produce sodium hydroxide (NaOH) and hydrogen chloride (HCl).
13. The method of claim 12, further comprising adding carbon dioxide (CO.sub.2) to sodium hydroxide (NaOH) obtained from the upper portion liquid to produce sodium carbonate (Na.sub.2CO.sub.3).
14. The method of claim 12, wherein the sodium hydroxide (NaOH) concentration in the upper portion liquid ranges from 3 weight percent to 50 weight percent.
15. The method of claim 11, further comprising extracting sodium chloride (NaCl) from the upper portion liquid.
16. The method of claim 15, wherein the extracting of sodium chloride is performed by reverse osmosis.
17. The method of claim 15, wherein the extracting of sodium chloride is performed by ion exchange.
18. The method of claim 11, wherein producing magnesium carbonate comprises using a process temperature ranging from 10 degrees Celsius to 90 degrees Celsius.
19. The method of claim 18, wherein producing magnesium carbonate comprises using a reaction time ranging from about two hours to about five hours.
20. A method for manufacturing carbonate, comprising: adding calcium oxide (CaO) to sea water solution to produce magnesium hydroxide (Mg(OH).sub.2); performing a first separation of the sea water solution to a supernatant portion, and a lower portion liquid, wherein the lower portion liquid comprises magnesium hydroxide (Mg(OH).sub.2); producing magnesium carbonate by adding carbon dioxide (CO.sub.2) to the lower portion liquid; electrolyzing the sodium chloride (NaCl) contained in the supernatant portion to produce sodium hydroxide (NaOH) and hydrogen chloride (HCl); adding sodium hydroxide (NaOH) obtained from the electrolyzing step into the supernatant portion to produce calcium hydroxide (Ca(OH).sub.2); performing a second separation of the supernatant portion to an upper portion liquid and a second lower portion liquid, the second lower portion liquid comprising calcium hydroxide (Ca(OH).sub.2); adding carbon dioxide (CO.sub.2) to the second lower portion liquid in S6 to produce calcium carbonate (CaCO.sub.3); and adding carbon dioxide (CO.sub.2) to sodium hydroxide (NaOH) obtained from the upper portion liquid to produce sodium carbonate (Na.sub.2CO.sub.3), wherein the upper portion liquid is maintained at room temperature, and with a reaction time ranging from ten minutes to five hours.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1) These and other features of this invention will be more readily understood from the following detailed description of the various aspects of the invention taken in conjunction with the accompanying drawings in which:
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DETAILED DESCRIPTION
(12) Referring to
(13) S1: manufacturing magnesium hydroxide (Mg(OH).sub.2) by adding calcium oxide (CaO) or calcium hydroxide (Ca(OH).sub.2) in seawater solution;
(14) S2: getting rid of supernatant in such seawater solution and separating lower portion liquid where magnesium hydroxide (Mg(OH).sub.2) is contained;
(15) S3: adding carbon dioxide (CO.sub.2) in such lower portion liquid where magnesium hydroxide (Mg(OH).sub.2) is contained to produce magnesium carbonate (MgCO.sub.3);
(16) S4: electrolyzing sodium chloride (NaCl) contained in supernatant disposed in S2 to produce sodium hydroxide (NaOH) as well as hydrogen chloride (HCl);
(17) S5: adding sodium hydroxide (NaOH) obtained from S4 in disposed supernatant from S2 to produce calcium hydroxide (Ca(OH).sub.2). In an alternative embodiment, for step S5, a CaCl.sub.2 (aq) solution is added to the supernatant and electrolyzed to acquire Ca(OH).sub.2 as per the following equation:
CaCl.sub.2+H.sub.2O.fwdarw.Ca(OH).sub.2+2HCl+H.sub.2O.fwdarw.Ca(OH).sub.2(precipitation)
(18) S6: disposing supernatant from S5 and separating lower portion liquid including calcium hydroxide (Ca(OH).sub.2);
(19) S7: adding carbon dioxide (CO.sub.2) in such lower portion liquid in S6 to produce calcium carbonate (CaCO.sub.3);
(20) S8: electrolyzing sodium chloride (NaCl) contained in disposed supernatant in S6 to produce sodium hydroxide (NaOH) as well as hydrogen chloride (HCl);
(21) S9: adding carbon dioxide (CO.sub.2) in sodium hydroxide (NaOH) obtained from S8 to produce sodium carbonate (Na.sub.2CO.sub.3);
(22) A more detailed description of the aforementioned steps of embodiments of the present invention is as follows:
(23) Sea water contains salts such as NaCl, MgCl.sub.2, MgSO.sub.4, CaSO.sub.4, and K.sub.2SO.sub.4. Table 1 shows exemplary amounts of each salt in 1000 kg of sea water.
(24) TABLE-US-00001 TABLE 1 Property (%) Kg NaCl 77.7 27.195 MgCl.sub.2 10.9 3.815 MgSO.sub.4 4.7 1.645 CaSO.sub.4 3.6 1.260 K2S0.sub.4 2.5 0.875 Misc 0.6 0.210 H.sub.2O 965.000
(25) When adding calcium oxide (CaO) (quick lime) or calcium hydroxide (Ca(OH).sub.2) (slaked lime) in such sea water solution containing these salts, magnesium chloride (MgCl.sub.2) as well as magnesium sulfate (MgSO.sub.4) react with calcium oxide or calcium hydroxide (reference reaction formula 1) and cause magnesium hydroxide (Mg(OH).sub.2) to precipitate, as shown in
(26) Reaction formula 1 for magnesium hydroxide is shown below:
MgCl.sub.2(aq)+CaO+H.sub.2O.fwdarw.Mg(OH).sub.2+CaCl.sub.2(aq)
(27) Subsequently, after going through a dehydration process of emitting supernatant in such sea water solution, such magnesium hydroxide (Mg(OH).sub.2) separate and cleanse the precipitated lower portion liquid (S2)
(28) When such magnesium hydroxide (Mg(OH).sub.2) adds carbon dioxide (CO.sub.2) in precipitated liquid, magnesium carbonate (MgCO.sub.3) becomes precipitated according to the following reaction formula: 2 (S3). If precipitated magnesium carbonate (MgCO.sub.3) is separated from this solution and cleansed, it becomes utilizable refined magnesium carbonate (MgCO.sub.3). At this time, magnesium hydroxide's (Mg(OH).sub.2) concentration is 540%, temperature is 10-90 C, and after 25 hours of reaction, it goes through a filtering and drying process. At this stage, carbon dioxide (CO.sub.2) consumption amounts to 2.365 g per 1 kg of sea water solution.
(29) The reaction formula 2 for magnesium carbonate is shown below:
Mg(OH).sub.2(s)+CO.sub.2(g)+H.sub.2O(l).fwdarw.MgCO.sub.3(s)+2H.sub.2O(l)
(30) Subsequently, sodium chloride contained in such separated supernatant is electrolyzed to produce sodium hydroxide (NaOH) as well as hydrogen chloride (HCl) (reference reaction formula 3: S4).
(31) The reaction formula 3 for sodium hydroxide is shown below:
2NaCl+2H.sub.2O.fwdarw.2NaOH+H.sub.2+Cl.sub.2
(32) If sodium hydroxide contained through such electrolysis is added to such supernatant, it reacts with sea water's calcium chloride (CaCl.sub.2) as well as calcium sulfate (CaSO.sub.4) (reference reaction formula 4) and cause calcium hydroxide (Ca(OH).sub.2) to precipitate (S5).
(33) The reaction formula 4 for calcium hydroxide is shown below:
CaCl.sub.2(aq)+2NaOH(aq).fwdarw.Ca(OH).sub.2(s)+NaCl(aq)
CaSO.sub.4(aq)+2NaOH(aq).fwdarw.Ca(OH).sub.2(s)+Na.sub.2SO.sub.4(aq)
(34) When calcium hydroxide (Ca(OH).sub.2) is precipitated, sea water solution's supernatant and lower portion liquid are again separated to form an upper portion liquid and a second lower portion liquid (S6).
(35) After dehydrating the lower portion liquid, calcium hydroxide (Ca(OH).sub.2) is cleansed and added with carbon dioxide (CO.sub.2), which ultimately results in calcium carbonate (CaCO.sub.3) to precipitate (S7). At this time, calcium hydroxide's (Ca(OH).sub.2) concentration is 540%, the process temperature is 1090 C, and the reaction is maintained for 25 hours and the calcium carbonate is subsequently filtered and dried. At this stage, carbon dioxide (CO.sub.2) consumption amounts to 2.365 g per 1 kg of sea water solution.
(36) The reaction formula 5 for calcium carbonate is shown below:
Ca(OH).sub.2(s)+CO.sub.2(g)+H.sub.2O(aq).fwdarw.CaCO.sub.3(s)+2H.sub.2O(aq)
(37) Successively, after dehydration and drying, utilizable refined calcium carbonate (CaCO.sub.3) is obtained.
(38) Subsequently, sodium chloride (NaCl) contained in supernatant separated in S6 is electrolyzed in order to produce sodium hydroxide (NaOH) as well as hydrogen chloride (HCl) (reference reaction formula 3: S8).
(39) Furthermore, if carbon dioxide is added to such electrolyzed sodium hydroxide (NaOH), sodium carbonate (Na.sub.2CO.sub.3) is produced (S9) (reference
(40) The total carbon dioxide consumption while carrying out steps S1-S9 amounts to 14.368 kg per 1000 kg of sea water.
(41) Table 2 shows carbonate produced according to embodiments of the present invention for manufacturing carbonate continuously and including carbon dioxide consumption; carbonate is produced by adding 3.013 kg of calcium oxide (CaO) per 1000 kg of sea water solution.
(42) TABLE-US-00002 TABLE 2 Substance Amount (kg) Additive CaO 3.013 Product & Remnant MgCO.sub.3 4.531 CaCO.sub.3 5.378 Na.sub.2CO.sub.3 23.211 Na.sub.2SO.sub.4 1.942 K.sub.2SO.sub.4 0.875 Misc 0.006 H.sub.2O 957.183 CO.sub.2 consumption 14.368
(43) According to embodiments of the present invention, magnesium carbonate (MgCO.sub.3), calcium carbonate (CaCO.sub.3) and sodium carbonate (Na.sub.2CO.sub.3) are each produced in amounts of, 4.531 kg, 5.378 kg and 23.211 kg, respectively per sea water solution of 1000 kg. Also, 14.368 kg of carbon dioxide is consumed.
(44) In addition, if magnesium carbonate (MgCO.sub.3), calcium carbonate (CaCO.sub.3), and sodium carbonate (Na.sub.2CO.sub.3) are manufactured successively, in accordance with embodiments of the present invention, refined versions of magnesium carbonate (MgCO.sub.3), calcium carbonate (CaCO.sub.3), and sodium carbonate (Na.sub.2CO.sub.3) are obtained, as shown in EDS graphs of either
(45) Referring specifically to
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(51) In contrast to embodiments of the present invention, if manufacturing carbonate by simply adding carbon dioxide to sea water solution as in prior art methods, one can see, as shown in EDS graph of
(52) This phenomenon is confirmed by XRD (X-ray Diffraction) property analysis and graphs. For reference, XRD is a technique with a main goal of judging crystal structure by measuring the refracted angle of X-rays surveyed on a sample. Depending on crystal structure as well as substance, absorption wavelength varies, and depending on such absorption wavelength, so does positional value (sin ).
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(54) On the other hand,
(55) Referring to
(56) Referring to
(57) As depicted in
(58) As such, as per embodiments of the present invention, by adding carbon dioxide in sea water, only insignificant (trace) amounts of impurities are produced during successive (continuous) manufacturing of refined magnesium carbonate (MgCO.sub.3) and calcium carbonate (CaCO.sub.3), as well as sodium carbonate (Na.sub.2CO.sub.3), and because these substances are refined, they can be utilized.
(59) On one hand, the aforementioned illustration describes that as a result of such manufacturing of calcium carbonate (CaCO.sub.3) (S7), sodium carbonate (Na.sub.2CO.sub.3) is manufactured through electrolysis and carbon dioxide addition.
(60) On the contrary, fresh water extraction such as reverse osmosis or ion exchange can be carried out against supernatant separated in S6 and separate water (H.sub.2O) and sodium chloride (NaCl), in order to gain high purity salinity.
(61) Embodiments of the present invention include the following steps:
(62) S1: manufacturing magnesium hydroxide (Mg(OH).sub.2) by adding calcium oxide (CaO) or calcium hydroxide (Ca(OH).sub.2) in seawater solution;
(63) S2: getting rid of supernatant in such seawater solution and separating lower portion liquid where magnesium hydroxide (Mg(OH).sub.2) is contained;
(64) S3: adding carbon dioxide (CO.sub.2) in such lower portion liquid where magnesium hydroxide (Mg(OH).sub.2) is contained to produce magnesium carbonate (MgCO.sub.3);
(65) S4: electrolyzing sodium chloride (NaCl) contained in supernatant disposed in S2 to produce sodium hydroxide (NaOH) as well as hydrogen chloride (HCl);
(66) S5: adding sodium hydroxide (NaOH) obtained from S4 in disposed supernatant from S2 to produce calcium hydroxide (Ca(OH).sub.2);
(67) In an alternative embodiment, for step S5, a CaCl.sub.2 (aq) solution is added to the supernatant and electrolyzed to acquire Ca(OH).sub.2 as per the following equation:
CaCl.sub.2+H.sub.2O.fwdarw.Ca(OH).sub.2+.sub.2HCl+H.sub.2O.fwdarw.Ca(OH).sub.2(precipitation)
(68) S6: disposing supernatant from S5 and separating lower portion liquid including calcium hydroxide (Ca(OH).sub.2); and
(69) S7: adding carbon dioxide (CO.sub.2) in such lower portion liquid in S6 to produce calcium carbonate (CaCO.sub.3).
(70) Embodiments of the present invention may further include the following additional steps to the above-mentioned steps: S8: electrolyzing sodium chloride (NaCl) contained in disposed supernatant in S6 to produce sodium hydroxide (NaOH), as well as hydrogen chloride (HCl); and S9: adding carbon dioxide (CO.sub.2) in sodium hydroxide (NaOH) obtained from S8 to produce sodium carbonate (Na.sub.2CO.sub.3).
(71) Embodiments of the present invention may further include an additional process of extracting sodium chloride (NaCl) from supernatant separated in S6 through fresh water extraction methods such as reverse osmosis or ion exchange, which is carried out subsequent to such step S7.
(72) Embodiments of the present invention may further comprise such calcium oxide (CaO) amount added to sea water solution to be less than 0.31% of weight of sea water.
(73) Embodiments of the present invention may further include manufacturing method features in the following steps: in S3, magnesium hydroxide's (Mg(OH).sub.2) concentration is 540%, temperature is 10-90 C, and after 25 hours of reaction, it goes through a filtering and drying process in order to produce magnesium carbonate (MgCO.sub.3); in S7, calcium hydroxide's (Ca(OH).sub.2) concentration is 540%, temperature is 1090 C, and reaction is kept for 25 hours and is then subsequently filtered and dried in order to produce calcium carbonate; in S9, sodium hydroxide (NaOH) concentration is 350%, is at room temperature, kept in reaction for 10 minutes5 hours, and finally enriched as well as dried in order to produce sodium carbonate (Na.sub.2CO.sub.3).
(74) The foregoing description of various aspects of the invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed and, obviously, many modifications and variations are possible. Such modifications and variations that may be apparent to a person skilled in the art are intended to be included within the scope of the invention as defined by the accompanying claims.