KR20220075904A - Manufacturing method of zeolite using lithium residue - Google Patents

Abstract

The present invention comprises the steps of preparing a lithium by-product; preparing a mixed powder raw material by mixing an alkali powder with the lithium by-product; and preparing a hydrogel solution by mixing a solvent with the mixed powder raw material; and preparing a hydrogel solution by mixing a solvent with the mixed powder raw material; is, the mixing water and the mixed powder raw material It relates to a method for producing a zeolite, wherein the weight ratio (water/solid lithium by-product ratio) of the solid lithium by-product contained in the is 15/1 to 37.5/1.

Description

Manufacturing method of zeolite using lithium by-product {MANUFACTURING METHOD OF ZEOLITE USING LITHIUM RESIDUE}

The present invention relates to a method for manufacturing zeolite using a lithium by-product, and more particularly, to a zeolite obtained by using a lithium by-product generated during a process of recovering lithium from lithium ore.

Zeolite (Zeolite, M[(Al ₂ O ₃ ) _x (SiO ₂ ) _y ] _z H ₂ O) is a laundry detergent (builder), removal of heavy metal ions in effluent, removal of harmful substances from exhaust gas (Removal of toxic materials from flue gases) It is a material used as a catalyst. This is because the unique applied mineralogical properties of zeolite, such as cation exchange capacity (CEC), adsorption and molecular sieve properties, catalytic properties, dehydration and resorption properties, etc., have been applied to related industries. It is being utilized and applied due to the fact that it has utility value.

In the study of zeolite synthesis, type A zeolite was first synthesized by Union Carbide's research team for industrial application purposes in 1949, and as the excellent applied mineralogical properties of type A synthetic zeolite became known, interest in zeolite synthesis increased Research followed. In the 1960s, research on zeolites began in earnest in the United States with the advent of new synthetic zeolites with excellent efficacy of Faujasite-type zeolites such as X-type and Y-type and successful application in petrochemical processes in the United States. In recent years, as the application range of zeolite has been greatly expanded, more diversity is required in the pore structure and characteristics of zeolite, and research to synthesize zeolite having a new pore structure and applied mineralogical properties has been conducted, and it is in the spotlight in industrial applications. About 150 kinds of synthetic zeolites have been developed, including ZSM-5 (Zeolite Socony Mobil-5), which is being accepted. As for the scope of application of zeolite, Z-X, a faujasite type zeolite, is used to remove carbon dioxide from exhaust gas or for gas drying, Linde type A type Z-A is a softener or gas desiccant in the detergent industry, and Z-P, a Gismondine type zeolite, is a softener or softener in the detergent industry. It is widely used as a wastewater treatment agent.

Zeolite synthesis is usually prepared by a so-called “hydrogel process” at a temperature ranging from room temperature to 200°C by a hydrothermal process. In general, zeolites do not require special pressure conditions in the production process and are relatively easily synthesized at low temperatures. Currently, reagent grade sodium silicate (Na ₂ SiO ₃ ), sodium aluminate (NaAlO ₂ ), and aluminum hydroxide (Al(OH) ₃ ), which are generally used as raw materials for zeolite synthesis, have a purity of 98% or more. Therefore, the quality of the zeolite manufactured using these raw materials is also manufactured with very high purity. The zeolite synthesized using these reagent raw materials has various pore characteristics as well as excellent performance and efficacy, but when applied in practice, it has some disadvantages in terms of price compared to cheaper natural zeolite. Therefore, efforts are currently underway to find a more cost effective method capable of homogeneously synthesizing zeolite having excellent properties.

As a cheaper synthesis method, natural materials that are cheaper than sodium silicate, sodium aluminate, silica gel, and fumed silica, which are reagent-type materials that have been mainly used as raw materials for zeolite synthesis, are used as raw materials, that is, silicate minerals having a composition suitable for zeolite synthesis. measures are being considered. Research on the synthesis of zeolite using natural minerals has mainly been made on clay, kaolin, kaolin, and volcanic vitreous rocks. In addition, research on using various by-products generated in large quantities in industrial processes as raw materials for zeolite synthesis instead of natural minerals with insufficient natural resources is being continuously conducted. As by-products of industrial process, fly ash, a representative material, paper sludge generated in the paper industry, waste sandstone cake generated in the mining process, fine crushed stone powder generated corresponding to 1 to 10% of raw stone in the stone or aggregate production process, aluminum manufacturing process There is growing interest in the possibility of manufacturing functional materials that can create added value along with recycling of by-products by using various by-products such as aluminum dross generated in steel mills and crushed slag powder generated in large quantities in the steelmaking process.

However, when zeolite is manufactured using natural minerals (clay, kaolin, kaolin, etc.), which are very inexpensive raw materials compared to reagent-grade raw materials, or by-products generated from industrial processes instead of natural minerals with insufficient natural resources, they are present in natural minerals or by-products generated by industrial processes. Various kinds of impure minerals and impurity components are introduced into the zeolite, which is the final product, and there is a problem that the quality deteriorates. Therefore, in order to manufacture zeolite of excellent quality using inexpensive raw materials such as natural minerals or by-products from industrial processes, methods for removing or reducing impurities in raw materials should be sought.

The present invention is to solve the problems of the prior art described above, and an object of the present invention is to use lithium by-products generated in a large amount in the process of recovering lithium from lithium ore and have excellent adsorption properties, and thus it is in the spotlight as a remover of carbon dioxide gas. It is to provide a zeolite in the form of Faujasite received and a method for manufacturing the same.

One aspect of the present invention comprises the steps of preparing a lithium by-product; preparing a mixed powder raw material by mixing an alkali powder with the lithium by-product; and preparing a hydrogel solution by mixing a solvent with the mixed powder raw material; and preparing a hydrogel solution by mixing a solvent with the mixed powder raw material; is, the mixing water and the mixed powder raw material It provides a method for producing a zeolite, wherein the weight ratio (water/solid lithium by-product ratio) of the solid lithium by-product contained in the is 15/1 to 37.5/1.

In one embodiment, adjusting the molar ratio of silicon to aluminum (Si/Al ratio) contained in the hydrogel solution by adding an alumina supplementary material or silica supplementary material to the hydrogel solution; may further include have.

In one embodiment, the adjusted molar ratio (Si/Al ratio) of silicon to aluminum contained in the hydrogel solution may be 1.25 to 3.5.

In one embodiment, the step of aging the hydrogel solution; may further include.

In one embodiment, the step of aging the hydrogel solution; the aging temperature may be 0 ℃ ~ 40 ℃.

In one embodiment, the step of aging the hydrogel solution; the aging time may be 6 hours or more.

In one embodiment, the step of crystallizing the hydrogel solution; may further include.

In one embodiment, the step of crystallizing the hydrogel solution; may be a crystallization temperature of 70 ℃ ~ 90 ℃.

In one embodiment, the step of crystallizing the hydrogel solution; the crystallization reaction time may be 9 hours or more.

In one embodiment, the step of crystallizing the hydrogel solution; may be a crystallization reaction while stirring at a stirring speed of 0rpm ~ 300rpm.

In one embodiment, preparing the lithium by-product; Thereafter, washing the lithium by-product with water to adjust the pH to 6 to 8; may further include.

In one embodiment, the alkali may include at least one of NaOH and KOH.

In one embodiment, the alumina supplement material may be sodium aluminate (NaAlO ₂ ).

In one embodiment, the silica supplement material may be sodium silicate (Na ₂ OSiO ₂ ).

In one embodiment, crystallizing the hydrogel solution; thereafter, filtering the crystals; washing the filtered crystals with water; and drying the washed crystals.

In one embodiment, washing the filtered crystals with water; adjusting the pH of the supernatant of the final product by the washing process to 10 or less; may be.

According to one aspect of the present invention, a gas adsorbent or laundry detergent builder that removes CO ₂ in exhaust gas by using a lithium by-product generated in a large amount in the process of recovering lithium from lithium ore as a raw material and has excellent adsorption properties. It is possible to obtain a Faujasite-type zeolite that can be used for this purpose.

According to another aspect of the present invention, by utilizing the lithium by-product generated in a large amount in the lithium recovery process as a functional material, it is possible to reduce the cost of disposing of the generated by-product as well as to manufacture a material with added value as an environmentally friendly functional material. can be used

In addition, according to another aspect of the present invention, it is possible to contribute to the construction of a resource circulation society by suggesting a method for recycling a large amount of lithium by-products.

1 is an electron micrograph of a zeolite prepared according to an embodiment of the present invention.
2 is an electron micrograph of a zeolite (Z-A+SOD) prepared according to a comparative example of the present invention.
3 is an electron micrograph of a zeolite (Faujasite+ZP) prepared according to another comparative example of the present invention.

The terms first, second and third etc. are used to describe, but are not limited to, various parts, components, regions, layers and/or sections. These terms are used only to distinguish one part, component, region, layer or section from another part, component, region, layer or section. Accordingly, a first part, component, region, layer or section described below may be referred to as a second part, component, region, layer or section without departing from the scope of the present invention.

The terminology used herein is for the purpose of referring to specific embodiments only, and is not intended to limit the present invention. As used herein, the singular forms also include the plural forms unless the phrases clearly indicate the opposite. The meaning of "comprising," as used herein, specifies a particular characteristic, region, integer, step, operation, element and/or component, and includes the presence or absence of another characteristic, region, integer, step, operation, element and/or component. It does not exclude additions.

When a part is referred to as being “on” or “on” another part, it may be directly on or on the other part, or the other part may be involved in between. In contrast, when a part is referred to as being "directly above" another part, the other part is not interposed therebetween.

In addition, unless otherwise specified, % means weight %, and 1 ppm is 0.0001 weight %.

In an embodiment of the present invention, the meaning of further including the additional element means that the remaining iron (Fe) is included by replacing the additional amount of the additional element.

Although not defined differently, all terms including technical and scientific terms used herein have the same meaning as those commonly understood by those of ordinary skill in the art to which the present invention pertains. Commonly used terms defined in the dictionary are additionally interpreted as having a meaning consistent with the related technical literature and the presently disclosed content, and unless defined, are not interpreted in an ideal or very formal meaning.

Hereinafter, embodiments of the present invention will be described in detail so that those of ordinary skill in the art can easily implement them. However, the present invention may be embodied in several different forms and is not limited to the embodiments described herein.

The present invention relates to a process for recovering lithium after flotation of lithium ore containing about 1.5% of Li ₂ O and concentration to about 6%, in particular, lithium ore heat treatment, grinding, sulfuric acid roasting, water leaching, and solid-liquid separation It relates to a method for producing a faujasite-type zeolite, which is in the spotlight as a carbon dioxide gas scavenger, because of its excellent adsorption properties using lithium by-products generated in large amounts in a series of processes.

Lithium ores are mainly composed of spodumene (LiAl ₂ SiO ₆ ) minerals, and the residue remaining after recovering Li by roasting sulfate and water leaching, that is, lithium by-products, is Al ₂ O ₃ 4SiO ₂ , and alumina and It is an aluminosilicate compound whose main component is silica, and as an impure mineral, mica (mica, (K,Ca,Na) ₂ , (Fe, Mg, Al, Mn, Fe, Ti) _4~6 (Si,Al) ₈ (OH,F)) and crystalline quartz (SiO ₂ ) occupying 90% of the earth's crust is a material containing at most about 10%.

Since zeolite is a material in which an alumina component and a silica component are composed of a network structure, various types of zeolite can be manufactured through an appropriate treatment process using lithium by-products composed of the same alumina component and silica component as the zeolite component. judge that there will be

Therefore, in the present invention, in the process of recovering lithium from lithium ore, in particular, the sum of the two components of silica and alumina generated in large amounts in a series of ore heat treatment, grinding, sulfuric acid roasting, water leaching, and solid-liquid separation is about 90 To provide a method for manufacturing X-type zeolite particles, which is a faujasite-type zeolite, which has excellent adsorption properties using lithium by-products present in the form of aluminosilicate compounds of % or more it is for

Hereinafter, each step of the lithium by-product and zeolite manufacturing method will be described in detail.

lithium by-product

In the process of recovering lithium from lithium ore, spodumene (Li ₂ O Al ₂ O ₃ 4SiO ₂ , LiAl ₂ Si ₂ O ₆ ), the main mineral phase of lithium ore, is water-soluble Li by the sulfuric acid roasting process and subsequent water leaching process. It is dissolved and leached into ₂ SO ₄ and can be recovered as Li by an appropriate neutralization reaction in a subsequent process.

On the other hand, in the solid-liquid separation process after water leaching, Al ₂ O ₃ and SiO ₂ , the remaining components of spodumene (Li ₂ O Al ₂ O ₃ 4SiO ₂ , LiAl ₂ Si ₂ O ₆ ), are aluminosilicate (Al ₂ O ₃ ). 4SiO ₂ , AlSi ₂ O ₆ ) It may remain in the form of a solid compound to constitute a lithium by-product.

The lithium by-product is Al ₂ O ₃ about 26% by weight, SiO ₂ about 66% by weight, Fe ₂ O ₃ 1.6% by weight, and in addition to CaO, Na ₂ O, K ₂ O, such as 0.1 to 0.4% by weight of alkali metals. It is a crystalline phase composed of aluminosilicate (Al ₂ O ₃ 4SiO ₂ , AlSi ₂ O ₆ ), quartz (SiO ₂ ), and albite, and has an average particle size of about 14 to 25 μm. It may be a material with

As the main mineral phase of lithium by-products, the aluminosilicate compound mineral phase (aluminosilicate, Albite) with a content of about 93% consists of silica and alumina, which are the main components of zeolite, so it can be used sufficiently as a raw material for synthetic zeolite. is judged However, in addition to the aluminosilicate compound mineral phase, which is the main component of zeolite, about 7% of quartz (SiO ₂ ), a very stable mineral form, is contained in the lithium by-product in about 7%. It is the main factor that deteriorates the quality of

The present invention converts the mineralogically very stable SiO ₂ mineral phase into a chemically soluble form through pre-treatment so that it can be used as a silica source, which is a component of zeolite, followed by an appropriate aging process and crystallization reaction of the reaction solution It is intended to manufacture X-type zeolite, which is a high-purity Faujasite-type zeolite, by blocking the inflow of an impurity, Quartz mineral.

Zeolite manufacturing method

A zeolite manufacturing method according to an aspect of the present invention comprises the steps of preparing a lithium by-product; preparing a mixed powder raw material by mixing an alkali powder with the lithium by-product; and preparing a hydrogel solution by mixing a solvent with the mixed powder raw material; and preparing a hydrogel solution by mixing a solvent with the mixed powder raw material; is, the mixing water and the mixed powder raw material The weight ratio (water/solid lithium by-product ratio) of the solid lithium by-product contained in may be 15/1 to 37.5/1.

Preparing the lithium by-product; heat-treating the lithium-containing ore; pulverizing the heat-treated lithium-containing ore; precipitating the lithium component in the pulverized lithium-containing ore as lithium sulfate; leaching the lithium sulfate into water; and obtaining a lithium residue by solid-liquid separation.

preparing the lithium by-product; Thereafter, washing the lithium by-product with water to adjust the pH to 6 to 8; may further include.

The step of adjusting the pH to 6 to 8 by washing the lithium by-product may be a step of removing the conjugate base of the acid from the lithium by-product. The conjugate base of the acid may be a sulfate group (SO ₄ ^2- ) resulting from sulfuric acid roasting during lithium water leaching.

The reason that lithium by-products are acidic is that, when roasting with sulfuric acid in the lithium ore pretreatment process, excess sulfuric acid is used, so the sulfuric acid remaining unreacted during water leaching is dissolved and included in the lithium by-products. Therefore, if the acidic lithium by-product containing the remaining sulfate group (SO ₄ ^2- ) is used as a raw material for zeolite production without washing with water, the remaining sulfate ion will consume the alkali component added for reaction with the lithium by-product raw material first. As a result, not only the addition of an excess of alkali is required, but also the added alkali component and the remaining sulfate group (SO ₄ ^2- ) ions react to form the salt (Na ₂ SO ₄ ). As a result, insoluble quartz It is not preferable because it interferes with the formation of a soluble mineral phase (SiO ₂ +NaOH->Na ₂ SiO ₃ ) formed by the reaction with the added alkali. Therefore, in order to use the acidic lithium by-product generated in the lithium recovery process as a raw material for manufacturing synthetic zeolite, the acidic lithium by-product is washed with sufficient water to remove sulfate group (SO ₄ ^2- ) ions to have a pH of 6 to 8. Manufacturing as a lithium by-product must be preceded.

Preparing a mixed powder raw material by mixing the alkali powder with the washed lithium by-product: uniformly mixing the alkali powder with the lithium by-product; and heat-treating the lithium by-product mixed with the alkali powder.

In the step of uniformly mixing the alkali powder with the lithium by-product; the alkali powder/lithium by-product weight ratio may be 1.0 or more. The SiO ₂ crystal phase disappeared in the mixed and heat-treated raw material prepared under the conditions of alkali powder/lithium by-product weight ratio of 1.0 or more, and the final product prepared through a crystallization reaction using a sample in which the SiO ₂ crystal phase disappeared is X-type zeolite can be created.

However, when the alkali powder/lithium by-product weight ratio is less than 1.0, the SiO ₂ crystal phase is in the same state as the raw material lithium by-product, and the final product prepared through the crystallization reaction using a sample in which the SiO ₂ crystal phase is mixed is an ion A problem that adversely affects the quality of zeolite, as it can be produced as a material in which various zeolite crystal phases and SiO ₂ crystal phases are mixed, such as P-type zeolite, X-type zeolite, etc. there is

Therefore, in the step of preparing a uniform mixture by mixing the lithium by-product and the alkali powder, the quartz (SiO ₂ ) crystal phase present in the lithium by-product is heated by adjusting the weight ratio of the alkali powder/lithium by-product to 1.0 or more. It is possible to improve the quality of synthetic zeolite by sufficiently reacting to form soluble substances (sodium silicate, sodium aluminate, sodium aluminum silicate), and by generating this sample as a single zeolite phase through the subsequent crystallization process.

The alkali may include at least one of NaOH and KOH.

Any of the alkali powders may be used as long as they provide the constituents necessary for the formation of zeolite. For example, NaOH supplying Na is preferable, and KOH may also be used. In addition, the alkali used can be uniformly mixed with the lithium by-product, and it is more preferable to use a powder form with high reactivity.

In the step of heat-treating the lithium by-product mixed with the alkali powder; in, the heat treatment temperature is 500 ℃ or more, the heat treatment time may be 30 minutes or more.

When the heat treatment temperature is less than 500 °C and the heat treatment time is less than 30 minutes, the SiO ₂ crystal phase present in the lithium by-product reacts with the added alkali powder and the activation energy (Ea) required for transition to a new crystal phase is insufficient, so it is a soluble form material. This is because the transition reaction to sodium silicate, sodium aluminate, sodium aluminum silicate, etc. does not proceed sufficiently. As for the heat treatment temperature and heat treatment time, it is sufficient to supply only the activation energy required for the complete transition of the reactant to a new product, and it is preferable to use as low energy as possible within the range of conditions that can supply the activation energy. If the heat treatment temperature is excessively high or the heat treatment time is excessively long, not only is it disadvantageous in terms of energy use, but also the lithium by-product and alkali, a low-melting compound, react after heat treatment to form a very strong bond. This is because another grinding energy is required in the process of refining the raw material for

Preparing a hydrogel solution by mixing a solvent with the mixed powder raw material; The weight ratio of the mixed water and the solid lithium by-product contained in the mixed powder raw material (hereinafter, "water/solid lithium by-product ratio") is 15 It can be /1 to 37.5/1.

In this specification, the water/solid lithium by-product ratio of 15/1 to 37.5/1 may be expressed as a water/mixed powder raw material ratio (alkali-fused powder, residue+alkali) of 6/1 to 15/1.

In the final product prepared under the condition that the water/solid lithium by-product ratio is less than 15/1, in addition to the Faujasite-type X zeolite crystal phase, the ion exchange capacity is small, so hydroxysodalite, Na ₈ (AlSiO ₆ ) ₄ (OH) ₂ Si ₂ O ₆ H ₂ O) is mixed and generated, so a single crystal phase of Faujasite-type zeolite with excellent adsorption properties cannot be prepared. In addition, the final product prepared under the condition that the water/solid lithium by-product ratio is more than 50/1 is not preferable because it does not precipitate as a zeolite crystal phase and is generated in an amorphous state, which is an amorphous state. When the water/solid lithium by-product ratio is less than 15/1, when the hydroxy sodalite crystal phase is mixed and generated, the amount of water to be mixed with the molten alkali powder as the raw material is relatively small, so it is used as an extractant that dissolves the raw material in this reaction system. As a condition in which the amount of alkali increases, the OH- ion concentration in the solution is increased, so that the X-type zeolite produced through the crystallization reaction is thermodynamically unstable and undergoes a phase change to hydroxy sodalite, which is a more stable crystalline phase under high OH- conditions. is judged When the water/solid lithium by-product ratio is more than 50/1, it does not precipitate as zeolite crystals and is produced in an amorphous state, which is an amorphous state. Due to this relatively insufficient OH- ion concentration, the reaction of effectively dissolving and extracting the amorphous hydrogel particles, which is the starting raw material, does not proceed. It is judged as the result that appeared because it remains as the top). However, the final product prepared by the crystallization reaction after adjusting the water/solid lithium by-product ratio within the range of 15/1 to 37.5/1 is produced as a single phase of Faujasite-type zeolite having excellent crystallinity.

The solvent used in the step of adjusting the water/solid lithium byproduct ratio may be water. Industrial water, general tap water, etc. can also be used as the water, but more preferably distilled water or ion-exchanged water can be used to exclude the inflow of other impurities including alkali metals such as Ca and Na. It is more preferable because it does not affect.

Controlling the molar ratio of silicon to aluminum (hereinafter, "Si/Al ratio") contained in the hydrogel solution by adding an alumina supplementary material or silica supplementary material to the hydrogel solution; may further include; The adjusted Si/Al ratio may be 1.25 to 3.5.

In the final product prepared under the condition of Si/Al ratio of 1.25 or less, in addition to the Faujasite-type zeolite crystal phase, hydroxy sodalite, which has low ion exchange capacity and low industrial application potential, is mixed and generated, so it is impossible to produce a single crystal phase of zeolite with excellent adsorption properties. do. In addition, it is not preferable because a Gismondine-type zeolite crystal phase in addition to the Faujasite-type zeolite crystal phase is mixed and generated in the final product prepared under the condition of a Si/Al ratio of 4.0 or more. However, the final product prepared through the crystallization reaction by adjusting the Si/Al ratio within the range of 1.50 to 3.50 is produced as a single phase of Faujasite-type X-zeolite having excellent crystallinity.

In the step of adjusting the Si / Al ratio by adding an alumina supplementary material or silica supplementary material to the hydrogel solution; sodium aluminate (NaAlO 2 ) as an alumina supplement material, and sodium silicate (Na ₂ OSiO ₂ ) as a silica supplement material ₂ ) is preferably used.

Silica supplement materials include silica gel, fumed silica, etc., and alumina supplement materials include aluminum hydroxide, but compared to these materials, the sodium aluminate (NaAlO ₂ ) and sodium silicate (Na ₂ OSiO ₂ ) are in aqueous solution. It has the advantage of being able to produce a reactant adjusted to a predetermined Si/Al ratio within a short time due to its high solubility in the compound, and thus it is more preferable to use it as a supplementary material.

It may further include; aging the hydrogel solution.

The step of aging the hydrogel solution; the aging temperature may be 0 ℃ ~ 40 ℃. Specifically, it may be in the range of 25 °C to 40 °C, more specifically in the range of 30 °C to 35 °C.

The step of aging the hydrogel solution; the aging time may be 6 hours or more. Specifically, it may be 6 hours to 24 hours, more specifically, 10 hours to 20 hours.

The meaning of "aging" is to generate and induce homogeneous zeolite nuclei from a reaction solution in the form of a hydrogel, which is an amorphous material. In general, when the aging temperature is high, the nucleation rate is fast, so that more nuclei are generated As a result, the amount of reactants contributing to crystal growth is reduced, and ultimately, the particle size of the produced material tends to decrease.

During aging, the stirring speed of the reaction solution is preferably a medium stirring speed at which the reaction solution can be uniformly mixed, and about 300 rpm is suitable for the medium stirring speed. If the reactants are not stirred during aging, the non-uniform reaction of the reaction solution results in poor particle size distribution of the final product. It is preferable to stir at a stirring speed of the order of magnitude.

The final product prepared by adjusting the aging temperature to 50 ° C. or higher is not preferable because hydroxy sodalite, which belongs to zeolite crystals other than the Faujasite-type zeolite crystal phase, but has low ion exchange ability and low industrial applicability, is mixed and produced. However, the final product prepared at the aging temperature in the range of 0°C to 40°C is produced as a single phase of Faujasite-type zeolite having very good crystallinity.

In the step of aging the reaction solution adjusted to an appropriate concentration, the aging time is preferably set to 6 hours or longer. The final product prepared under the condition of aging time of 3 hours or less showed very non-uniform particle size distribution for large particles of about 1.7 to 3.5 μm and for small particles of about 0.3 to 0.5 μm. However, the final product prepared under the condition that the aging time is 6 hours or more shows a relatively homogeneous particle size distribution compared to the product prepared by adjusting the aging time to 3 hours or less, with large particles of about 1.7 μm and small particles of about 0.7 to 1.0 μm. it was If the aging time is not performed or the aging time is insufficiently 3 hours or less, the non-uniformity of the particle size distribution of the final product increases. do.

It may further include; crystallizing the hydrogel solution.

Crystallizing the hydrogel solution; may be a crystallization temperature of 70 ℃ ~ 90 ℃. Specifically, it may be in the range of 75 °C to 90 °C, more specifically in the range of 75 °C to 85 °C.

Crystallizing the hydrogel solution; crystallization reaction time may be 9 hours or more. Specifically, it may be 9 hours to 24 hours, more specifically 12 hours to 20 hours.

The step of crystallizing the hydrogel solution; the step of reacting at a stirring speed of 0rpm ~ 300rpm; may be.

The thermodynamically stable phase sequence of zeolite according to temperature is Faujasite (X, Y-type zeolite) -> Linde Type A (Z-A) -> Gismondene (Z-P) -> SOD. Among the various types of zeolites, the most thermodynamically stable zeolite is It is hydroxy sodalite, and the most unstable form is known as faujasite type X-type and Y-type zeolite. In particular, Faujasite-type X-type and Y-type zeolite is known to be produced only under certain limited synthetic conditions as well as a narrow formation area, so it is known that it is very difficult to prepare it as a single crystal phase.

The final product prepared by setting the crystallization temperature to less than 70° C. is not preferable because it exists in an amorphous state, which is an amorphous state, or crystals are precipitated in some Faujasite-type zeolite, but exists in an amorphous state in a large amount. In the final product manufactured by setting the crystallization temperature to 100°C or higher, in addition to faujasite-type zeolite, hydroxy sodalite, which has low ion exchange capacity and low industrial application potential, is mixed and produced. cannot be manufactured The reason why hydroxy sodalite is mixed and produced under the condition that the crystallization reaction temperature is 100° C. or higher is that the thermodynamically very unstable X-type zeolite undergoes a phase change to hydroxy sodalite, which is a more stable phase at high temperatures.

In the final product prepared by carrying out the crystallization time under the condition of less than 9 hours, an amorphous phase in an amorphous state coexist in addition to the X-type zeolite, so that a single X-type zeolite cannot be prepared. The reason for the coexistence of amorphous amorphous phases under the condition of crystallization time of less than 9 hours is that the amorphous reaction solution is mixed as it is due to insufficient dissolution and extraction by hydroxyl ions.

When the crystallization reaction is carried out by setting the stirring speed of the reaction solution very fast to about 500 rpm, the final product is Z-P-type zeolite in addition to X-type zeolite. When the stirring speed is performed at a very high speed as described above, the reason that Z-P type zeolite is mixed and produced in addition to X-type zeolite is that X-type zeolite, which is a thermodynamically metastable phase, receives external force such as high temperature or high stirring speed to make more stable crystals. It is judged as a result of the phase transition to the merchant Z-P. On the other hand, the final product prepared under the condition that the stirring speed was set at a stationary state (stirring speed 0 rpm) or 300 rpm or less was prepared as a single phase X-type zeolite having excellent crystallinity. Therefore, in the crystallization step of precipitating the hydrogel solution into zeolite crystals through the crystallization reaction by increasing the temperature, it is preferable to proceed the reaction solution in a non-agitated (stationary) state or to react while stirring at a stirring speed of 300 rpm or less.

crystallizing the hydrogel solution; thereafter, filtering the crystals; washing the filtered crystals with water; and drying the washed crystals.

Washing the filtered crystals with water; adjusting the pH of the supernatant of the final product by the water washing process to 10 or less; may be.

In the step of separating the zeolite crystals by solid-liquid separation after crystallization, sufficiently washing the separated zeolite crystals with water and drying to recover the final product, the excess NaOH remaining in the produced zeolite is removed by sufficient water washing to remove the final product. It is preferable to adjust the supernatant pH to 10 or less. This is because Na ions remaining in the product due to insufficient water washing act as a cause of deterioration of the quality and performance of the zeolite. Therefore, in the step of recovering the final product prepared by crystallization, it is preferable to adjust the pH of the supernatant of the final product to a condition of 10 or less by removing the excess NaOH remaining in the final product by a sufficient water washing process.

Hereinafter, embodiments of the present invention will be described in detail so that those of ordinary skill in the art can easily implement them. However, the present invention may be embodied in various different forms, and is not limited to the embodiments described herein.

Preparation Example - Preparation of alkali molten powder raw material

Lithium ore containing about 1.5% of Li ₂ O content was removed by flotation, etc. to remove feldspar and mica, and then concentrated to about 6% Li ₂ O content. Then, the particle size was adjusted by grinding to improve reactivity in the subsequent process.

95% sulfuric acid was added 3 times by weight to β-spodumene whose particle size was adjusted, mixed, and then roasted with sulfuric acid at 250° C. for 1 hour.

After roasting sulfuric acid, 5 times the weight of water was added, stirred, water leached for 1 hour, and solid-liquid separation was performed using a filter press, and lithium by-products generated in this process were recovered.

The lithium by-product generated in the lithium recovery process is sufficiently dried in a dryer, 15 kg of distilled water is added to 3 kg of the completely dried lithium by-product, the solid-liquid ratio (lithium by-product/water) is adjusted to 1/5, stirred at 500 rpm for 3 hours, and filtered, The drying sequence was repeated three times to prepare a lithium by-product having a pH of 6 to 8.

The prepared lithium by-product component ratio of pH 6 to 8 is 13.09% Al and 31.43% Si, and the Si/Al ratio is 2.40 as a raw material.

The lithium by-product raw material washed with water was used as a raw material as it was, without adjusting the components.

After adding 75 g of alkali powder to 50 g of lithium by-product and adjusting the alkali powder/lithium by-product ratio (weight ratio) to 1.50, use a tumbler mixer to uniformly mix the mixture, and put the sample of the homogeneous mixture into an alumina crucible, in a muffle furnace ) at a temperature increase rate of 10°C/min. and maintained at 550°C for 1.5 hours, followed by furnace cooling to prepare an alkali molten sample.

In order to improve the reactivity in the subsequent reaction of the sample, which is agglomerated by reaction of lithium by-product and alkali in the heat treatment process, using a pulverizer, run at 1500 rpm for 3 minutes to prepare an alkali molten sample into powder, and use this sample as a starting material was used as

Examples 1 to 7

After adding the powdered sample, that is, 125 g of an alkali molten powder sample prepared by mixing 50 g of lithium by-product and 75 g of NaOH alkali in the above preparation example, into a 2L glass reactor, the water/solid lithium by-product ratio ((water, g)/(lithium) 750ml, 833ml, 938ml, 1072ml, 1250ml, 1500ml, 1875ml of distilled water so that by-product, g)) is 15/1, 17/1, 19/1, 22/1, 25/1, 30/1, 37.5/1 were respectively added and stirred to prepare a slurry, that is, a hydrogel.

Thereafter, the hydrogel reaction solution was aged for 6 hours while stirring at 25° C. at a stirring speed of 300 rpm, and then the temperature of the reaction solution was raised to 90° C. while stirring at 300 rpm.

When the reaction temperature reached 90° C., stirring was stopped and the crystallization reaction was carried out while maintaining it in a stationary state (no stirring) for 24 hours.

After the crystallization reaction was completed, the sample was repeatedly washed with water until the pH of the supernatant was 10 or less, and the washed sample was filtered and dried sufficiently at 105° C. to prepare a final product.

Comparative Examples 1 to 3

It was carried out in the same manner as in Examples 1 to 7, except that 625 ml, 2500 ml, and 3750 ml of distilled water were respectively added so that the water/solid lithium byproduct ratio was 12.5/1, 50/1, and 75/1.

Experimental Example 1

The crystal phases of the final products prepared in Examples 1 to 7 and Comparative Examples 1 to 3 were analyzed by XRD and the particle shape by SEM, respectively, and the results are shown in Table 1 below, and the Faujasite type prepared in Example 3 The SEM image of the zeolite is shown in FIG. 1 .

division Liquid/Hump (weight ratio)
(Water/Lithium by-product) amount of water added
(ml) crystalline phase
(XRD) particle shape
(SEM) Example One 15/1 750 Faujasite (Z-X, 100%) Octahedral 2 17/1 833 Faujasite (Z-X, 100%) Octahedral 3 19/1 938 Faujasite (Z-X, 100%) Octahedral 4 22/1 1072 Faujasite (Z-X, 100%) Octahedral 5 25/1 1250 Faujasite (Z-X, 100%) Octahedral 6 30/1 1500 Faujasite (Z-X, 100%) Octahedral 7 37.5/1 1875 Faujasite (Z-X, 100%) Octahedral comparative example One 12.5/1 625 Faujasite (ZX, 90.9%)
+
SOD (9.1%) Octahedral
+
Wool ball-like shape 2 50/1 2500 amorphous Shapeless 3 75/1 3750 amorphous Shapeless

As shown in Examples 1 to 7 of Table 1, the final product prepared by reacting by adjusting the water/solid lithium by-product ratio within the range of 15/1 to 37.5/1 was XRD analysis, one of the Faujasite zeolite types, Type X As a single phase of zeolite, it was prepared as particles with excellent crystallinity, and as a result of SEM observation, it was confirmed that the particle size distribution showed a uniform octahedral shape. However, as in Comparative Example 1, the water/solid lithium byproduct ratio was adjusted to 12.5/1. In this case, in addition to the X-type zeolite, an SOD crystal phase was mixed and generated, and as in Comparative Examples 2 and 3, when the water/solid lithium by-product ratio was adjusted to 50/1 or more, it was observed as an amorphous phase in an amorphous state.

Under the conditions of Comparative Example 1, that is, when the amount of water is relatively small compared to the lithium by-product, the amount of hydroxyl ions (OH-) present in the reaction solution is high. These hydroxyl ions dissolve and extract the amorphous hydrogel material initially formed by the addition of water. Since the X-type zeolite produced through the crystallization reaction is a thermodynamically metastable phase, if the reaction is continued for a long time in an environment with a relatively high hydroxyl ion concentration, it transitions to a more stable phase, SOD.

The conditions of Comparative Examples 2 and 3 are opposite to those of Comparative Example 1, and the amount of hydroxyl ions present in the reaction solution is small because the amount of water is relatively large compared to the lithium by-product. Considering the action of hydroxyl ions to dissolve and extract the initially formed amorphous hydrogel to form zeolite, the amount of hydroxyl ions corresponding to the above conditions cannot dissolve the amorphous hydrogel, so it is in the amorphous state as the starting material. It is judged that it has been maintained and appeared as a final product.

Therefore, the amount of water added to the alkali molten powder is the water/solid lithium byproduct ratio 15/1 to 37.5/ in which hydroxyl ions having sufficient solubility to sufficiently dissolve and extract the initially formed amorphous hydrogel can be formed. It can be confirmed that it is preferable to react by adjusting within the range of 1.

Examples 8 to 16

After putting in the powdered sample, that is, 125 g of the alkali molten powder sample prepared by mixing 50 g of lithium by-product and 75 g of NaOH alkali in the above preparation example, into a 2L glass reactor, 938 ml of distilled water was added so that the water/solid lithium by-product ratio was 19/1 It was added and stirred to prepare a slurry.

To adjust the Si/Al ratio of the prepared hydrogel reaction solution, Na ₂ SiO ₃ was used as a silica source and NaAlO ₂ was used as an alumina source, respectively.

NaAlO ₂ and Na ₂ SiO ₃ were added to the prepared hydrogel reaction solution, respectively, and the Si/Al ratio was adjusted to 1.25, 1.50, 1.75, 2.0, 2.25, 2.4, 2.50, 3.0, 3.5, respectively.

After adjusting the Si/Al ratio, the mixture was stirred to prepare a slurry, that is, a hydrogel. Thereafter, the hydrogel reaction solution was aged for 6 hours while stirring at 25° C. at a stirring speed of 300 rpm, and then the temperature of the reaction solution was raised to 90° C. while stirring at 300 rpm.

When the reaction temperature reached 90° C., the stirring was stopped and the crystallization reaction was carried out while maintaining it in a stationary state (no stirring) for 24 hours.

After the crystallization reaction was completed, the sample was repeatedly washed with water until the pH of the supernatant was 10 or less, and the washed sample was filtered and dried sufficiently at 105° C. to prepare a final product.

Comparative Examples 4 to 6

It was carried out in the same manner as in Examples 8 to 16, except that the Si/Al ratio of the reaction solution was adjusted to 1.0, 4.0, and 5.0, respectively.

Experimental Example 2

The crystal phases of the final products prepared in Examples 8 to 16 and Comparative Examples 4 to 6 were analyzed by XRD and the particle shape by SEM, and the results are shown in Table 2 below, respectively, and prepared in Comparative Examples 4 and 6 SEM images of the zeolite are shown in FIGS. 2 and 3 .

division reaction solution
S/A ratio Add
NaAlO ₂ (g) Add
Na ₂ SiO ₃ (g) crystalline phase
(XRD) Particle shape (SEM) Example 8 1.25 19.27 - Faujasite (Z-X, 100%) Octahedral 9 1.50 12.57 - Faujasite (Z-X, 100%) Octahedral 10 1.75 7.78 - Faujasite (Z-X, 100%) Octahedral 11 2.0 4.19 - Faujasite (Z-X, 100%) Octahedral 12 2.25 1.40 - Faujasite (Z-X, 100%) Octahedral 13 2.4 - - Faujasite (Z-X, 100%) Octahedral 14 2.50 - 4.68 Faujasite (Z-X, 100%) Octahedral 15 3.0 - 28.1 Faujasite (Z-X, 100%) Octahedral 16 3.50 - 51.5 Faujasite (Z-X, 100%) Octahedral comparative example 4 1.0 29.33 - Linde Type A (ZA, 86.4%)
+
SOD (13.6%) Cubic
+
Wooo ball-like shape 5 4.0 - 74.9 Faujasite (ZX, 61.8%)
+
Gismondine (ZP, 38.2%) Octahedral
+
Cactus-like shape 6 5.0 - 121.6 Faujasite (ZX, 84.6%)+
Gismondine (ZP, 15.4%) Octahedral
+
Cactus-like shape

As shown in Examples 8 to 16 of Table 2, after adjusting the S/A ratio of the reaction solution within the range of 1.25 to 3.50, the final product prepared by reacting was a faujasite type having very good crystallinity according to the XRD analysis result. It can be confirmed that the X-type zeolite is formed as a single phase, and according to the SEM analysis result, it can be confirmed that the X-type zeolite exhibits an octahedral shape, which is the intrinsic shape of the zeolite. However, as in Comparative Example 4, the final product prepared under the condition of a very low S/A ratio with an S/A ratio of 1.0 was confirmed to be produced by mixing the Linde Type A type, cubic type A zeolite, and the zeolite initial product type, SOD. can

And as in Comparative Examples 5 and 6, it can be seen that the final product prepared by adjusting the S/A ratio to be higher than 4.0 is produced by mixing the P-type zeolite of the Gismondine type in addition to the X-type zeolite of the Faujasite type.

The S/A ratio of the reaction solution is the most important factor in determining the zeolite form of the final product. In general, the A-type zeolite has an S/A ratio of about 1.0 to 1.50, and the P-type zeolite has an S/A ratio of 2.0 to 2.5. In the vicinity, Faujasite-type zeolite is known to be produced only in a very narrow area with an S/A ratio of around 1.0.

However, according to the present Examples (8 to 16), it can be confirmed that the Faujasite type X-type zeolite can be prepared in a very wide area with an S/A ratio of 1.25 to 3.50.

Therefore, in adjusting the S/A ratio, which is the most important factor determining the shape of the finally produced zeolite, in order to produce an octahedral X-type zeolite with very good crystallinity, the S/A ratio was adjusted in the range of 1.25 to 3.50. It can be confirmed that the post-crystallization reaction is preferable.

Examples 17-18

In the 2L glass reactor, 125 g of the powdered sample, that is, 125 g of the molten alkali powder sample prepared by mixing 50 g of lithium by-product and 75 g of NaOH alkali in the above preparation example, was added, and then 938 ml of distilled water was added so that the water/solid lithium by-product ratio was 19/1. and stirred to prepare a slurry, that is, a hydrogel.

Thereafter, the hydrogel reaction solution was aged for 6 hours while stirring at 25°C and 40°C at a stirring speed of 300 rpm, and then the temperature of the reaction solution was raised to 90° C. while stirring at 300 rpm.

When the reaction temperature reached 90° C., the stirring was stopped and the crystallization reaction was carried out while maintaining it in a stationary state (no stirring) for 24 hours.

After the crystallization reaction was completed, the sample was repeatedly washed with water until the pH of the supernatant was 10 or less, and the washed sample was filtered and dried sufficiently at 105° C. to prepare a final product.

Comparative Example 7

It was carried out in the same manner as in the above example, except that the hydrogel reaction solution was aged at 50 °C.

Experimental Example 3

The crystal phases of the final products prepared in Examples 17 to 18 and Comparative Example 7 were analyzed by XRD and the particle shape by SEM, respectively, and the results are shown in Table 3 below.

division aging temperature
(℃) crystalline phase
(XRD) Particle shape (SEM) Example 17 25 Faujasite (Z-X, 100%) Octahedral 18 40 Faujasite (Z-X, 100%) Octahedral comparative example 7 50 Faujasite (ZX, 92.4%)
+
SOD (7.6%) Octahedral
+
wool ball-like shape

As shown in Examples 17 and 18 of Table 3, the final product prepared by setting the aging temperature of the hydrogel reaction solution to 25°C and 40°C, respectively, was a single phase X-type zeolite in the form of faujasite with excellent crystallinity. It was observed that the particle size of the final product prepared by setting the aging temperature to 40°C was slightly smaller than that of the product prepared at 25°C.

This is an induction period in which the aging temperature generates zeolite nuclei. If the aging temperature is relatively high, the nucleation rate is faster and thus a greater number of nuclei are generated. Therefore, if a lot of nucleation occurs in a given reaction solution, the amount of the remaining material that can contribute to growth is relatively small, so the amount of material contributing to growth is small. do.

It can be seen that the final product prepared under the conditions of the aging temperature of 50° C. of Comparative Example 7 is mixed with and generated SOD, which is an initial product of zeolite, in addition to the Faujasite type X zeolite.

This appears to be a phenomenon occurring because, when the aging temperature reaches 50 °C, the initial reactant, amorphous hydrogel, starts to crystallize slowly, although the reaction rate is slow due to the increase in internal energy as the temperature rises, and partly undergoes a phase transition to SOD, an initial zeolite form.

Therefore, it can be confirmed that it is preferable to crystallize the Faujasite type X-type zeolite single phase to proceed by adjusting the aging temperature to 40° C. or less during the aging process corresponding to the zeolite nucleation induction period.

Examples 19-21

In the 2L glass reactor, 125 g of the powdered sample, that is, 125 g of the molten alkali powder sample prepared by mixing 50 g of lithium by-product and 75 g of NaOH alkali in the above preparation example, was added, and then 938 ml of distilled water was added so that the water/solid lithium by-product ratio was 19/1. and stirred to prepare a slurry, that is, a hydrogel.

Thereafter, the hydrogel reaction solution was aged at an aging temperature of 25° C. while stirring at 300 rpm for 6 hours, 12 hours, and 24 hours, and then the temperature of the reaction solution was raised to 90° C. while stirring at 300 rpm.

When the reaction temperature reached 90° C., the stirring was stopped and the crystallization reaction was carried out while maintaining it in a stationary state (no stirring) for 24 hours.

After the crystallization reaction was completed, the sample was repeatedly washed with water until the pH of the supernatant was 10 or less, and the washed sample was filtered and dried sufficiently at 105° C. to prepare a final product.

Comparative Examples 8 to 10

It was carried out in the same manner as in the above example, except that when the hydrogel reaction solution was directly crystallized without aging (aging time 0), and aged for 1 hour and 3 hours, respectively.

Experimental Example 4

The crystal phases of the final products prepared in Examples 19 to 21 and Comparative Examples 8 to 10 were analyzed by XRD, and the particle shape, particle size, and particle size distribution uniformity were analyzed by SEM, respectively, and the results are shown in Table 4 below.

division ripening time
(hour) crystalline phase
(XRD) particle shape
(SEM) Particle size (SEM) particle size distribution Example 19 6 Faujasite (Z-X, 100%) Octahedral (Large: 1.60㎛ / Small: 1.0㎛) uniform 20 12 Faujasite (Z-X, 100%) Octahedral (Large: 1.7㎛ / Small: 0.7㎛) uniform 21 24 Faujasite (Z-X, 100%) Octahedral (Large: 1.7㎛ / Small: 0.7㎛) uniform comparative example 8 0 Faujasite (Z-X, 100%) Octahedral (Large: 3.4㎛ / Small: 0.5㎛) very uneven 9 One Faujasite (Z-X, 100%) Octahedral (Large: 2.7㎛ / Small: 0.4㎛) very uneven 10 3 Faujasite (Z-X, 100%) Octahedral (Large: 1.7㎛ / Small: 0.3㎛) very uneven

As shown in Examples 19 to 21 of Table 4, the final products prepared by aging the hydrogel reaction solution at 25° C. for 6 hours or more were all produced as Faujasite type X zeolite, and in particular, the produced octahedral particle size was It was confirmed that the particle size distribution was generated as very uniform particles. As the aging time increases, the particle size distribution becomes more uniform and the particle size tends to become smaller. However, as shown in Comparative Examples 8 to 10, the final product prepared under the condition of the aging time of 3 hours or less is in the form of faujasite. It can be seen that although it is produced as a single phase of X-type zeolite, the particle size distribution of the product is very non-uniform. In particular, in the product of Comparative Example 8, which was directly crystallized without going through an aging process, large particles were produced to about 3.4 μm and small particles to about 0.5 μm, respectively, indicating a very heterogeneous particle size distribution.

As mentioned earlier, this is the period during which the aging process induces the nucleation of zeolite crystals from the amorphous hydrogel. As the maturation time increases, the initially formed non-uniform zeolite nuclei dissolve and contact with hydroxyl ions, which are extractants. It is thought that this is because it plays a role in generating more uniform nuclei by partially dissolving by

Therefore, it can be confirmed that it is preferable to induce uniform nucleation by aging the hydrogel reaction solution for 6 hours or more in order to produce a faujasite-type X-type zeolite having a more uniform particle size distribution.

Examples 22 to 24

In the 2L glass reactor, after adding 125 g of the powdered sample, that is, the alkali molten powder sample prepared by mixing 50 g of lithium by-product and 75 g of NaOH alkali in the above preparation example, 938 ml of distilled water was added so that the water/solid lithium by-product ratio was 19/1 and stirred to prepare a slurry, that is, a hydrogel.

Thereafter, the hydrogel reaction solution was aged at an aging temperature of 25° C. while stirring at 300 rpm for 24 hours, and then the temperature of the reaction solution was raised to 70° C., 80° C. and 90° C. while stirring at 300 rpm.

When the reaction temperature reached 70°C, 80°C, and 90°C, the stirring was stopped and the crystallization reaction was carried out while maintaining it in a stationary state (no stirring) for 24 hours.

After the crystallization reaction was completed, the sample was repeatedly washed with water until the pH of the supernatant was 10 or less, and the washed sample was filtered and dried sufficiently at 105° C. to prepare a final product.

Comparative Examples 11 to 13

The temperature of the reaction solution was adjusted to 50°C, 60°C, and 100°C, respectively, and the crystallization reaction was carried out in the same manner as in the above example.

Experimental Example 5

The crystal phases of the final products prepared in Examples 22 to 24 and Comparative Examples 11 to 13 were analyzed by XRD and the particle shape by SEM, respectively, and the results are shown in Table 5 below.

division crystallization reaction temperature
(℃) crystalline phase
(XRD) particle shape
(SEM) Example 22 70 Faujasite (Z-X, 100%) Octahedral 23 80 Faujasite (Z-X, 100%) Octahedral 24 90 Faujasite (Z-X, 100%) Octahedral comparative example 11 50 amorphous Shapeless 12 60 Faujasite (ZX, 100%)
+
amorphous Octahedral
+
Shapeless 13 100 Faujasite (ZX, 92.8%)+
SOD (7.2%) Octahedral
+
Wool ball-like

As shown in Examples 22 to 24 of Table 5, the final product prepared by adjusting the crystallization reaction temperature within the range of 70 to 90 ° C. It can be confirmed that a single phase of X-type zeolite, which is an octahedral faujasite form with excellent crystallinity, is produced. However, as in Comparative Examples 11 to 12, the final product prepared by adjusting the crystallization reaction temperature to a temperature of 60° C. or lower exists in an amorphous state or contains a large amount of amorphous material although some X-type zeolite is produced. is manufactured

This is a result that the initial product, amorphous hydrogel, did not undergo effective dissolution reaction by hydroxyl ions due to the low reaction temperature.

On the other hand, as shown in Comparative Example 13, the final product prepared by adjusting the reaction temperature to 100° C. contains SOD, a high-temperature stable phase, in addition to the Faujasite type X zeolite.

This is considered to be a result of the fact that the generated X-type zeolite becomes thermodynamically unstable at a high reaction temperature and partially undergoes a phase transition to SOD, which is a more stable crystalline phase at high temperature.

Therefore, it can be confirmed that when the reaction solution hydrogel is subjected to a crystallization reaction to precipitate zeolite crystals, it is preferable to prepare the reaction solution by adjusting the crystallization reaction temperature within the range of 70°C to 90°C.

Examples 25-30

In the 2L glass reactor, after adding 125 g of the powdered sample, that is, the alkali molten powder sample prepared by mixing 50 g of lithium by-product and 75 g of NaOH alkali in the above preparation example, 938 ml of distilled water was added so that the water/solid lithium by-product ratio was 19/1 and stirred to prepare a slurry, that is, a hydrogel.

Thereafter, the hydrogel reaction solution was aged at an aging temperature of 25° C. while stirring at 300 rpm for 24 hours, and then the temperature of the reaction solution was raised to 90° C. while stirring at 300 rpm.

When the reaction temperature reached 90° C., stirring was stopped and the crystallization reaction was carried out while maintaining them in a stationary state (no stirring) for 9 hours, 12 hours, 15 hours, 18 hours, 21 hours, and 24 hours, respectively.

After the crystallization reaction was completed, the sample was repeatedly washed with water until the pH of the supernatant was 10 or less, and the washed sample was filtered and dried sufficiently at 105° C. to prepare a final product.

Comparative Examples 14 to 15

The reaction solution was carried out in the same manner as in the above example, except that the reaction solution was crystallized at a temperature of 90° C. for 3 hours and 6 hours, respectively.

Experimental Example 6

The crystal phases of the final products prepared in Examples 25 to 30 and Comparative Examples 14 to 15 were analyzed by XRD and the particle shape by SEM, respectively, and the results are shown in Table 6 below.

division crystallization reaction time
(h) crystalline phase
(XRD) particle shape
(SEM) Example 25 9 Faujasite (Z-X, 100%) Octahedral 26 12 Faujasite (Z-X, 100%) Octahedral 27 15 Faujasite (Z-X, 100%) Octahedral 28 18 Faujasite (Z-X, 100%) Octahedral 29 21 Faujasite (Z-X, 100%) Octahedral 30 24 Faujasite (Z-X, 100%) Octahedral comparative example 14 3 Faujasite (ZX, 100%)
+
amorphous Octahedral
+
Shapeless 15 6 Faujasite (ZX, 100%)
+
amorphous Octahedral
+
Shapeless

As shown in Examples 25 to 30 of Table 6, it can be confirmed that the final product prepared by adjusting the crystallization reaction time to 9 hours or more is prepared as a single phase X-type zezolite, which is an octahedral faujasite form with excellent crystallinity. However, as shown in Comparative Examples 14 to 15, it can be confirmed that the final product prepared by setting the crystallization reaction time to 6 hours or less still remains in an amorphous state, which is an unreacted material.

Therefore, in order to prepare a single phase of X-type zeolite in the form of faujasite with excellent crystallinity, the time for the amorphous hydrogel to sufficiently react with hydroxyl ions to transform into zeolite crystals, that is, the crystallization reaction time is set to 9 hours or more. It can be confirmed that this is preferable.

Examples 31 to 33

In the 2L glass reactor, 125 g of the powdered sample, that is, 125 g of the molten alkali powder sample prepared by mixing 50 g of lithium by-product and 75 g of NaOH alkali in the above preparation example, was added, and then 938 ml of distilled water was added so that the water/solid lithium by-product ratio was 19/1. and stirred to prepare a slurry, that is, a hydrogel.

Thereafter, the hydrogel reaction solution was aged at an aging temperature of 25° C. while stirring at 300 rpm for 24 hours, and then the temperature of the reaction solution was raised to 90° C. while stirring at 300 rpm.

When the reaction temperature reached 90° C., the crystallization reaction was carried out by maintaining for 24 hours while maintaining each of the non-agitated state (0 rpm), the stirring speed of 100 rpm and the stirring speed of 300 rpm.

After the crystallization reaction was completed, the sample was repeatedly washed with water until the pH of the supernatant was 10 or less, and the washed sample was filtered and dried sufficiently at 105° C. to prepare a final product.

Comparative Example 16

It was carried out in the same manner as in the above example, except that the reaction solution was crystallized at a temperature of 90° C. and a stirring speed of 500 rpm for 24 hours.

Experimental Example 7

The crystal phases of the final products prepared in Examples 31 to 33 and Comparative Example 16 were analyzed by XRD and the particle shape by SEM, respectively, and the results are shown in Table 7 below.

division Stirring speed (rpm) crystalline phase
(XRD) particle shape
(SEM) Example 31 0 Faujasite (Z-X, 100%) Octahedral 32 100 Faujasite (Z-X, 100%) Octahedral 33 300 Faujasite (Z-X, 100%) Octahedral comparative example 16 500 Faujasite (ZX, 97.5%)
+
Gismondine (ZP, 2.5%) Octahedral
+
Cactus-like shape

As shown in Examples 31 to 33 of Table 7, when the hydrogel reaction solution is crystallized, the stirring speed is set to 0 rpm and the stirring speed is maintained in a stationary state, or the final product prepared by crystallization reaction while stirring at a stirring speed of 300 rpm or less is It was possible to prepare a single phase of X-type zeolite, which is an octahedral faujasite type with excellent crystallinity. However, as shown in Comparative Example 16, the final product prepared at a stirring speed of 500rpm was not only X-type zeolite, but also Gismondine-type P-type zeolite. It can be confirmed that they are mixed and created.

This is considered to be due to the characteristic that the thermodynamically very unstable X-type zeolite transitions to a more stable phase, Z-P, when subjected to external force such as temperature or rapid stirring.

Therefore, it can be confirmed that, when the hydrogel reaction solution is crystallized, it is preferable to maintain it in a stationary state (no stirring) or to react at a stirring speed of 300 rpm or less.

The present invention is not limited to the embodiments, but can be manufactured in various different forms, and those of ordinary skill in the art to which the present invention pertains can use other specific forms without changing the technical spirit or essential features of the present invention. It will be appreciated that this may be practiced. Therefore, it should be understood that the embodiments described above are illustrative in all respects and not restrictive.

Claims (16)

preparing a lithium by-product;
preparing a mixed powder raw material by mixing an alkali powder with the lithium by-product; and
Including; mixing a solvent with the mixed powder raw material to prepare a hydrogel solution;
Preparing a hydrogel solution by mixing a solvent with the mixed powder raw material;
The weight ratio of the mixed water and the solid lithium by-product contained in the mixed powder raw material (water/solid lithium by-product ratio) is 15/1 to 37.5/1, a zeolite manufacturing method. According to claim 1,
Adjusting the molar ratio of silicon to aluminum (Si/Al ratio) contained in the hydrogel solution by adding an alumina supplement material or a silica supplement material to the hydrogel solution; further comprising, a zeolite manufacturing method. 3. The method of claim 2,
The controlled molar ratio (Si / Al ratio) of silicon to aluminum contained in the hydrogel solution is 1.25 to 3.5, a zeolite manufacturing method. According to claim 1,
Aging the hydrogel solution; further comprising, a zeolite manufacturing method. 5. The method of claim 4,
Aging the hydrogel solution;
The aging temperature is 0 ℃ ~ 40 ℃, zeolite manufacturing method. 5. The method of claim 4,
Aging the hydrogel solution;
The aging time is 6 hours or more, zeolite manufacturing method. According to claim 1,
Further comprising; crystallizing the hydrogel solution; zeolite manufacturing method. 8. The method of claim 7,
Crystallizing the hydrogel solution;
The crystallization temperature is 70 ℃ ~ 90 ℃, zeolite manufacturing method. 8. The method of claim 7,
Crystallizing the hydrogel solution;
A method for producing a zeolite, wherein the crystallization reaction time is 9 hours or more. 8. The method of claim 7,
Crystallizing the hydrogel solution;
A method for producing a zeolite, wherein the crystallization reaction is carried out while stirring at a stirring speed of 0 rpm to 300 rpm. According to claim 1,
preparing the lithium by-product; Since the,
Adjusting the pH to 6 to 8 by washing the lithium by-product; further comprising, a zeolite manufacturing method. According to claim 1,
The alkali comprises at least one of NaOH and KOH, zeolite manufacturing method. 3. The method of claim 2,
wherein the alumina supplement material is sodium aluminate (NaAlO ₂ ). 3. The method of claim 2,
wherein the silica supplemental material is sodium silicate (Na ₂ OSiO ₂ ). 8. The method of claim 7,
crystallizing the hydrogel solution; Since the,
filtering the crystals;
washing the filtered crystals with water; and
Drying the washed crystals; further comprising, a zeolite manufacturing method. 14. The method of claim 13,
Washing the filtered crystals with water; is,
Adjusting the pH of the supernatant of the final product by the water washing process to 10 or less; phosphorus, a zeolite manufacturing method.

Images