CN102849776B

CN102849776B - Gel-solid phase reaction preparation method for Li2CuO2 high temperature carbon absorption material

Info

Publication number: CN102849776B
Application number: CN201210330140.6A
Authority: CN
Inventors: 张超武; 徐彬; 刘昌涛; 王金磊; 王芬
Original assignee: Shaanxi University of Science and Technology
Current assignee: Shaanxi University of Science and Technology
Priority date: 2012-09-07
Filing date: 2012-09-07
Publication date: 2014-06-04
Anticipated expiration: 2032-09-07
Also published as: CN102849776A

Abstract

The invention relates to a gel-solid phase reaction preparation method for a Li2CuO2 high temperature carbon absorption material. According to the present invention, copper nitrate is dissolved in deionized water; concentrated ammonia water is diluted with deionized water, and then is mixed with citric acid and urea to prepare an amino mixed solution; under constant stirring, the copper nitrate solution is added to the amino mixed solution, and continuous pH detection is performed until the pH value is 3.9-4.1; heating is performed to a temperature of 45-55 DEG C; constant temperature stirring is continuously performed for 1 hour, and then standing is performed to obtain a light blue Cu(OH)2 gel; the Cu(OH)2 gel is subjected to soaking, washing, filtering and drying to obtain nascent Cu(OH)2 nanometer powder; and finally the prepared Cu(OH)2 nanometer powder and a lithium source are subjected to grinding, mixing and tablet pressing according to a molar ratio of Li:Cu of 2:1, and then are subjected to reaction sintering for 18-24 hours in an electric heating furnace at a temperature of 720-760 DEG C to obtain the dark blue Li2CuO2 material. The test results show that the product prepared by the method is a monoclinic crystal Li2CuO2, and has characteristics of good crystal and high purity, wherein CO2 saturation absorption amount under a CO2 atmosphere at a temperature of 675 DEG C can be about 35%(wt).

Description

A kind of Li 2cuO 2high temperature is inhaled the gel-casting reaction method for preparing of carbon material

Technical field

The invention belongs to environmentally conscious materials field, relate in particular to a kind of Li ₂cuO ₂high temperature is inhaled the gel-casting reaction method for preparing of carbon material.

Background technology

Along with the improvement day by day of rapid development of economy and people's life, as main greenhouse gases CO ₂quantity discharged also day by day increase, the mankind's safety has been arrived in serious threat.Reduce CO ₂the safety that isothermal chamber gas enters atmosphere, to protect mankind living environment is one of current global key problem urgently to be resolved hurrily.

The burning of fossil oil is CO ₂main emission source.Because the gas temperature discharging in High Temperature Furnaces Heating Apparatus is higher, to CO in flue gas ₂separation conventionally will be through a series of processing such as cooling, this in the serious power loss of generation, has also increased absorption CO undoubtedly ₂required cost.Therefore be badly in need of in high-temperature flue gas, directly absorbing CO ₂high performance material, to reduce the CO discharging from High Temperature Furnaces Heating Apparatus ₂gas, this has very great meaning for environment protection and control Global warming.

Copper acid lithium Li ₂cuO ₂that a kind of novel high temperature is inhaled carbon material, it at high temperature (550 ~ 675 ℃) directly absorb the CO discharging in High Temperature Furnaces Heating Apparatus ₂gas, without through techniques such as coolings, has higher receptivity.Inhale in carbon material Li at current several lithium bases ₂cuO ₂theoretical absorptive capacity maximum, reach 40.1%.And absorb CO ₂having reversibility, is that the very potential high temperature of one is inhaled carbon material, for reducing CO in High Temperature Furnaces Heating Apparatus ₂discharge new technological approaches is provided.

At present about Li ₂cuO ₂preparation method be mainly adopt with cupric oxide CuO and Quilonum Retard Li ₂cO ₃the solid phase method of powder stock hybrid reaction.Although it is fairly simple that this method operates, but exist following shortcoming: one, general powder stock granularity is all thicker, and thick particle passes through higher calcining temperature (more than 800 ℃) and the longer reaction times of contact interface reaction needed, thereby synthesis temperature is high, power consumption large, efficiency is low; Its two, Li ₂cO ₃fusing point be 618 ℃, under the high temperature more than 800 ℃, become already the melt that mobility is very large, alkaline corrosion is very strong, more Li ₂cO ₃have little time just to react and poured off with cupric oxide, the residual more CuO of result final product, purity is not high; Crucible is produced to larger corrosion simultaneously.Its three, larger feed particles powder is often difficult to mix, and causes reactively uneven, easily produces local burning or underburnt, thereby makes product produce more impurity, this is also the reason that can not get high-purity product.

Summary of the invention

The object of the invention is to overcome the shortcoming of above-mentioned solid phase method, provide a kind of preparation method simple, can be to environment, and calcining temperature is low, finally improves the Li of product purity ₂cuO ₂high temperature is inhaled the gel-casting reaction method for preparing of carbon material.

For achieving the above object, the technical solution used in the present invention is:

1) ammoniacal liquor is made into the ammonia soln that concentration is 0.8-1.2mol/L with deionized water, then according to ammoniacal liquor: citric acid: urea=1:(0.1-0.15): mol ratio (0.1-0.15) joins citric acid and urea in ammonia soln, makes amino mixing solutions;

2) by analytically pure Cu (NO ₃) ₂3H ₂o is dissolved in and in deionized water, is made into the copper nitrate aqueous solution that concentration is 0.6-0.65mol/L.Then amino mixing solutions is placed in temperature control magnetic stirring apparatus, under stirring at room temperature, copper nitrate solution is slowly added in amino mixing solutions, and monitor continuously the variation of pH, in the time that pH value reaches 3.9 ~ 4.1, stop adding opening temp. control power supply, be heated to 45～55 ℃, and continue constant temperature and stir 1h, leave standstill 30 ~ 40min, obtain light blue copper hydroxide Cu (OH) ₂gel;

3) copper hydroxide gel is soaked, washs, filtered with deionized water, until inspection does not measure nitrate ion, then it is dry at 40 ~ 50 ℃ to be placed in baking oven, obtains the nano copper hydroxide powder of nascent state;

4) adopt Li ₂cO ₃or LiOH is lithium source, by the copper hydroxide nano-powder making and lithium source according to the ratio ground and mixed of mol ratio Li:Cu=2:1 evenly and compressing tablet;

5) the sample suppressing is obtained to highly purified mazarine copper acid lithium Li in 720 ~ 760 ℃ of reaction sintering 18 ~ 24h in electrothermal oven ₂cuO ₂sample.

Described Cu (NO ₃) ₂3H ₂o adopts analytically pure Cu (NO ₃) ₂3H ₂o.

The present invention takes to have the cupric oxide nano of higher melt, the measure of sensitization especially, to strengthen it and to have the reactivity of greater activity lithium salts, thereby reaches refinement precursor granularity, reduction calcining temperature the final object that improves product purity.For this reason, the present invention is with cupric nitrate Cu (NO ₃) ₂3H ₂o, as copper source, adopts the very strong nascent state nano copper hydroxide Cu (OH) of sol-gel method preparation feedback activity ₂gel to be to replace common cupric oxide powder powder stock, then with Li ₂cO ₃or LiOH hybrid reaction is prepared high-purity Li ₂cuO ₂.The present invention can not only reduce synthesis temperature, reduces power consumption, and the more important thing is the Li making ₂cuO ₂purity is high, CO ₂absorptive capacity is large.In addition, preparation method of the present invention is simple, and can be to environment, is a kind of Li of practicability and effectiveness ₂cuO ₂material synthesis method.

Accompanying drawing explanation

Fig. 1 is for adopting analytical pure CuNO ₃3H ₂o copper source and Li ₂cO ₃lithium source is at 750 ℃ of sintering 24h gained sample Li ₂cuO ₂xRD figure;

Fig. 2 is the Li of Fig. 1 ₂cuO ₂sample is CO under differing temps ₂saturated adsorption discharge curve.

Embodiment

Embodiment 1:

1) ammoniacal liquor is made into the ammonia soln that concentration is 1mol/L with deionized water, then according to ammoniacal liquor: the mol ratio of citric acid: urea=1:0.1:0.1 joins citric acid and urea in ammonia soln, makes amino mixing solutions;

2) by analytically pure Cu (NO ₃) ₂3H ₂o is dissolved in and in deionized water, is made into the copper nitrate aqueous solution that concentration is 0.6mol/L, then amino mixing solutions is placed in the temperature control magnetic stirring apparatus that model is 85-2 type, under stirring at room temperature, copper nitrate solution is slowly added in amino mixing solutions, and monitor continuously the variation of pH, in the time that pH value reaches 3.9, stop adding, opening temp. control power supply, is heated to 45 ℃, and continues constant temperature and stir 1h, leave standstill 30min, obtain light blue copper hydroxide Cu (OH) ₂gel;

3) copper hydroxide gel is soaked, washs, filtered with deionized water, until inspection does not measure nitrate ion, then it is dry at 40 ℃ to be placed in baking oven, obtains the nano copper hydroxide powder of nascent state;

4) adopt Li ₂cO ₃for lithium source, by the copper hydroxide nano-powder making and lithium source according to the ratio ground and mixed of mol ratio Li:Cu=2:1 evenly and compressing tablet;

5) the sample suppressing is obtained to highly purified mazarine copper acid lithium Li in 750 ℃ of reaction sintering 24h in electrothermal oven ₂cuO ₂sample.

Resulting materials is CO at 675 ℃ ₂saturated absorption amount reach 35.5%(wt).

In order to verify validity of the present invention, the Li that embodiment 1 is made ₂cuO ₂sample has carried out following test analysis checking.

1, X-ray diffractometer (XRD) test

As seen from Figure 1, diffraction peak and PDF standard card 84-1971 coincide, and peak shape is sharp-pointed, and intensity is high, shows that the synthetic sample of the present invention is oblique system Li ₂cuO ₂, crystalline condition is good, and purity is very high, almost there is no dephasign.

2, Li ₂cuO ₂absorbed CO ₂performance

In order to investigate prepared Li ₂cuO ₂the CO of sample ₂absorptive character, have measured the saturated extent of adsorption of sample under differing temps.Method is that sample is put into tube-type atmosphere furnace, passes into CO ₂gas, is incubated 40min to 1 hour at a certain temperature, measures the quality change of inhaling carbon front and back, can calculate saturated extent of adsorption.In Fig. 2, can find out Li ₂cuO ₂material has maximum saturation adsorptive capacity at 675 ℃, and its maximal absorptive capacity exceedes 35%, shows to absorb CO ₂functional.

Embodiment 2:

1) ammoniacal liquor is made into the ammonia soln that concentration is 0.8mol/L with deionized water, then according to ammoniacal liquor: the mol ratio of citric acid: urea=1:0.12:0.12 joins citric acid and urea in ammonia soln, makes amino mixing solutions;

2) by analytically pure Cu (NO ₃) ₂3H ₂o is dissolved in and in deionized water, is made into the copper nitrate aqueous solution that concentration is 0.65mol/L, then amino mixing solutions is placed in the temperature control magnetic stirring apparatus that model is 85-2 type, under stirring at room temperature, copper nitrate solution is slowly added in amino mixing solutions, and monitor continuously the variation of pH, in the time that pH value reaches 4.0, stop adding, opening temp. control power supply, is heated to 50 ℃, and continues constant temperature and stir 1h, leave standstill 33min, obtain light blue copper hydroxide Cu (OH) ₂gel;

3) copper hydroxide gel is soaked, washs, filtered with deionized water, until inspection does not measure nitrate ion, then it is dry at 43 ℃ to be placed in baking oven, obtains the nano copper hydroxide powder of nascent state;

4) adopting LiOH is lithium source, by the copper hydroxide nano-powder making and lithium source according to evenly compressing tablet also of the ratio ground and mixed of mol ratio Li:Cu=2:1;

5) the sample suppressing is obtained to highly purified mazarine copper acid lithium Li in 720 ℃ of reaction sintering 22h in electrothermal oven ₂cuO ₂sample.

Resulting materials is CO at 675 ℃ ₂saturated absorption amount reach 34.8%(wt).

Embodiment 3:

1) ammoniacal liquor is made into the ammonia soln that concentration is 1.0mol/L with deionized water, then according to ammoniacal liquor: the mol ratio of citric acid: urea=1:0.14:0.14 joins citric acid and urea in ammonia soln, makes amino mixing solutions;

2) by analytically pure Cu (NO ₃) ₂3H ₂o is dissolved in and in deionized water, is made into the copper nitrate aqueous solution that concentration is 0.63mol/L, then amino mixing solutions is placed in the temperature control magnetic stirring apparatus that model is 85-2 type, under stirring at room temperature, copper nitrate solution is slowly added in amino mixing solutions, and monitor continuously the variation of pH, in the time that pH value reaches 4.1, stop adding, opening temp. control power supply, is heated to 48 ℃, and continues constant temperature and stir 1h, leave standstill 37min, obtain light blue copper hydroxide Cu (OH) ₂gel;

3) copper hydroxide gel is soaked, washs, filtered with deionized water, until inspection does not measure nitrate ion, then it is dry at 48 ℃ to be placed in baking oven, obtains the nano copper hydroxide powder of nascent state;

5) the sample suppressing is obtained to highly purified mazarine copper acid lithium Li in 740 ℃ of reaction sintering 20h in electrothermal oven ₂cuO ₂sample.

Resulting materials is CO at 675 ℃ ₂saturated absorption amount reach 35.1%(wt).

Embodiment 4:

1) ammoniacal liquor is made into the ammonia soln that concentration is 1.2mol/L with deionized water, then according to ammoniacal liquor: the mol ratio of citric acid: urea=1:0.15:0.15 joins citric acid and urea in ammonia soln, makes amino mixing solutions;

2) by analytically pure Cu (NO ₃) ₂3H ₂o is dissolved in and in deionized water, is made into the copper nitrate aqueous solution that concentration is 0.62mol/L, then amino mixing solutions is placed in the temperature control magnetic stirring apparatus that model is 85-2 type, under stirring at room temperature, copper nitrate solution is slowly added in amino mixing solutions, and monitor continuously the variation of pH, in the time that pH value reaches 4.0, stop adding, opening temp. control power supply, is heated to 55 ℃, and continues constant temperature and stir 1h, leave standstill 40min, obtain light blue copper hydroxide Cu (OH) ₂gel;

3) copper hydroxide gel is soaked, washs, filtered with deionized water, until inspection does not measure nitrate ion, then it is dry at 50 ℃ to be placed in baking oven, obtains the nano copper hydroxide powder of nascent state;

5) the sample suppressing is obtained to highly purified mazarine copper acid lithium Li in 760 ℃ of reaction sintering 18h in electrothermal oven ₂cuO ₂sample.

Resulting materials is CO at 675 ℃ ₂saturated absorption amount reach 34.6%(wt).

Claims

1. a Li ₂cuO ₂high temperature is inhaled the gel-casting reaction method for preparing of carbon material, it is characterized in that comprising the following steps:

2) by analytically pure Cu (NO ₃) ₂3H ₂o is dissolved in and in deionized water, is made into the copper nitrate aqueous solution that concentration is 0.6-0.65mol/L, then amino mixing solutions is placed in temperature control magnetic stirring apparatus, under stirring at room temperature, copper nitrate solution is slowly added in amino mixing solutions, and monitor continuously the variation of pH, in the time that pH value reaches 3.9～4.1, stop adding, opening temp. control power supply, is heated to 45～55 ℃, and continues constant temperature and stir 1h, leave standstill 30～40min, obtain light blue copper hydroxide Cu (OH) ₂gel;

3) copper hydroxide gel is soaked, washs, filtered with deionized water, until inspection does not measure nitrate ion, then it is dry at 40～50 ℃ to be placed in baking oven, obtains the nano copper hydroxide powder of nascent state;

5) the sample suppressing is obtained to highly purified mazarine copper acid lithium Li in 720～760 ℃ of reaction sintering 18～24h in electrothermal oven ₂cuO ₂sample.