CN101979309B - Method for preparing hydrotalcite from egg shells serving as raw material - Google Patents

Abstract

The invention provides a method for preparing hydrotalcite from egg shells serving as a raw material. The method comprises the following steps of: drying the egg shells at the temperature of between 313 and 393K DEG C for 1 to 12 hours, and then roasting at the temperature of between 573 and 1,273K DEG C for 1 to 12 hours to obtain a roasted product; adding 0.56 to 2.24 grams of roasted product into every 20 to 50 milliliters of distilled water, stirring the mixture for 5 to 100 minutes, and mixing the mixture and 20 to 50 milliliters of salt solution containing trivalent metal ions to obtain the reaction solution in a molar ratio of Ca to the trivalent metal ion of 5:1-2:1; and reacting the reaction solution for 0.5 to 48 hours, and filtering and drying to obtain the hydrotalcite. The method for preparing the hydrotalcite is simple, has low cost, and is favorable for actual production; and the raw materials such as NaOH, ammonia water and the like do not need to be added to provide an alkaline environment, sodium salt does not need to be added to provide intercalation anions, and divalent metal ions required for preparing the hydrotalcite are derived from the egg shells.

Description

With the eggshell is the method for feedstock production hydrotalcite

Technical field

That the present invention relates to is a kind of preparation method of hydrotalcite.

Background technology

The special construction of hydrotalcite (LDHs) is given its diversified physicochemical property, makes it demonstrate wide application prospect in fields such as catalysis, intercalation, medicament slow release, er material, fire-retardant, WWT, function luminescent material and semi-conductors.But consume a large amount of solubility divalence and trivalent salt, sodium hydroxide and provide the sodium salt of interlayer anion to be unfavorable for actual production owing to prepare needs in the process at traditional hydrotalcite, so hydrotalcite application in the production of reality, life is less.

People such as A.V.Radha are raw material with nitrocalcite and aluminum nitrate and regulate pH with sodium hydroxide; Adopt the method for co-precipitation to synthesize calcium aluminum hydrotalcite (A.V.Radha, P.Vishnu Kamath, C.Shivakumara; Solid State Sciences.1180,7 (2005)).People such as Kristy L.Erickson utilize Wyler's process to prepare the zinc-aluminium hydrotalcite of carbonate intercalation; Be to add certain amount of urea in 2: 1 zinc chloride and the liquor alumini chloridi with molar concentration rate; The alkaline condition and carbonate synthetic hydrotalcite (Kristy L.Erickson, Thor E.Bostrom, the Ray L.Frost that utilize ureaclastic product to provide; Materials Letters.226,59 (2005)).Human ammoniacal liquor such as J.Olanrewaju provide the alkaline environment synthetic hydrotalcite; Its main compound method is: under different temperature, ammoniacal liquor is joined reaction in magnesium nitrate and the aluminum nitrate solution of different mol ratio, filtration, washing, drying respectively and make hydrotalcite.In this experiment, alkaline environment is provided and also is cited as compound method with sodium hydroxide and oppose than testing (J.Olanrewaju, B.L.Newalkar, C.Mancino, S.Komarneni, Materials Letters.307, (45) 2000) with microwave-assisted.People such as Feng Yang join the aluminium sesquioxide film in the solution that contains hexamethyl four ammonia and zinc nitrate, and at the hydrotalcite of film surface growth in situ, hexamethyl four ammonia provide required alkaline environment (Feng Yang in this process; Bo Yu Xie; Jing Zhi Sun, Jia Ke Jin, Mang Wang; Materials Letters.1302,62 (2008)).

In sum, the preparation process of hydrotalcite mainly can be divided into following a few step: at first, configuration contains the divalence and the trivalent metal salts solution of certain mol proportion; In alkaline environment, make precipitation by metallic ion then; Utilize different supplementary meanss to improve its percent crystallinity again; At last, filter repeatedly, wash, drying promptly makes hydrotalcite.Though these methods can obtain required hydrotalcite; But because the metal-salt and the alkali cost that in the preparation process, add are higher; This has improved the production cost of hydrotalcite indirectly and has made it and in the production application of reality, has been restricted (Kok-Hui Goh, Teik-Thye Lim, ZhiliDong; Water Research.1343,42 (2008); Jaime S.Valente; Manuel S á nchez-Cant ú; Enrique Lima;

Figueras, Chem.Mater.5809-5818,21 (2009); S.K.Sharma, P.K.Kushwaha, V.K.Srivastava, S.D.Bhatt, R.V.Jasra, Ind.Eng.Chem.Res.46 (14), 4856 (2007)).

Summary of the invention

The object of the present invention is to provide a kind of simple, cost is low and what be beneficial to actual production is the method for feedstock production hydrotalcite with the eggshell.

The objective of the invention is to realize like this:

(1) with the surface cleaning clean egg shell behind dry 1-12h under the 313-393K temperature at 573-1273K roasting temperature 1-12h, make product of roasting;

(2) ratio according to product of roasting 0.56-2.24g adding zero(ppm) water 20-50mL adds product of roasting in the zero(ppm) water; Stir 5-100min; With the salt solution mix that contains the 20-50mL trivalent metal ion, the mol ratio that obtains Ca and trivalent metal ion is 5: 1-2: 1 reaction solution;

(3) behind the reaction solution reaction 0.5-48h, filter, be drying to obtain hydrotalcite product.

Described eggshell is Ovum crusta Gallus domesticus, Ovum Anas domestica putamina or Ovum-crusta Anseris domestica and their mixture thereof.

Said three metals ions are Al ³⁺, Fe ³⁺Or Cr ³⁺And their mixture.

The present invention is directed to the problem that exists among the existing hydrotalcite preparation method, providing a kind of is the method for feedstock production hydrotalcite with the eggshell, this method be a kind of simply, cheaply and be beneficial to the hydrotalcite preparation method of actual production.Present method need not added raw materials such as NaOH, ammoniacal liquor in the preparation process of hydrotalcite provide alkaline environment, need not add sodium salt intercalant anion is provided, and form the required divalent-metal ion of hydrotalcite all from life waste material-eggshell.

Divalent-metal ion calcium on the hydrotalcite laminate that makes all derives from eggshell.It is to be provided by the CaO hydrolysis in the eggshell product of roasting that hydrotalcite prepares alkaline environment required in the process.Can adopt hydrothermal method, coprecipitation method, microwave-assisted synthetic, ultrasonic auxiliary synthetic etc.Its interlayer anion can be: inorganic anions such as cl ions, nitrate ion, carbanion, sulfate radical can also be organic anions such as Hydrocerol A, oxalic acid.

Description of drawings

Fig. 1 is the original position XRD figure of the hydrotalcite that makes.

Fig. 2 is the FT-IR figure of the hydrotalcite that makes.

Embodiment

For example the present invention is done in more detail below and describes:

Embodiment 1:

The fresh eggshell that surface cleaning is clean moves into behind the dry 1h under 353K in the retort furnace, roasting 1h under 1173K.The a certain amount of product of roasting that obtains is added a small amount of zero(ppm) water to be stirred behind the 30min and contains AlCl ₃The salts solution 20mL of metals ion mixes, and promptly gets reaction solution (wherein the Ca/Al mol ratio is 4: 1).Reaction solution is reacted 2h after-filtration, washing, dry under 353K, both made hydrotalcite.

Embodiment 2:

Change roasting Ovum crusta Gallus domesticus and AlCl ₃Mol ratio, other experiment condition can make the hydrotalcite material of Different Ca/Al mol ratio with embodiment 1.

Embodiment 3:

With the AlCl among the embodiment 1 ₃Change into Al (NO ₃) ₃, Al ₂(SO ₄) ₃Can obtain the hydrotalcite of different anions intercalation.

Embodiment 4:

With the AlCl among the embodiment 1 ₃Change into FeCl ₃, CrCl ₃Can obtain containing different metal ionic hydrotalcite.

Embodiment 5:

With the AlCl among the embodiment 1 ₃Replace to obtain ternary or polywater talcum with two or more salt.

Claims (2)

1. one kind is the method for feedstock production hydrotalcite with the eggshell, it is characterized in that:

(1) with the surface cleaning clean egg shell behind dry 1-12h under the 313-393K temperature at 573-1273K roasting temperature 1-12h, make product of roasting;

(2) ratio according to product of roasting 0.56-2.24g adding zero(ppm) water 20-50mL adds product of roasting in the zero(ppm) water; Stir 5-100min; With the salt solution mix that contains the 20-50mL trivalent metal ion, the mol ratio that obtains Ca and trivalent metal ion is 5: 1-2: 1 reaction solution; Said trivalent metal ion is Al ³⁺, Fe ³⁺, Cr ³⁺In a kind of or their mixture

(3) behind the reaction solution reaction 0.5-48h, filter, be drying to obtain hydrotalcite product.

2. according to claim 1 is the method for feedstock production hydrotalcite with the eggshell, it is characterized in that: described eggshell is a kind of in Ovum crusta Gallus domesticus, Ovum Anas domestica putamina, the Ovum-crusta Anseris domestica or their mixture.