CZ9903807A3 - Suspension exhibiting high storage stability containing aqueous solution of silicate and binding agent - Google Patents

Abstract

A high storage stability suspension comprising aqueous a silicate solution and a filler wherein the silicate solution has a content silicates of at least 20% by weight; a particle size of 0.8 to 15 µm and a specific gravity of less than 2.75 kg / l, wherein the filler is selected from the group consisting of: a) zeolites; (b) fine particulate amorphous inorganic material; \ tor. \ t fibers which is relatively inert to the alkaline aqueous a solution containing amorphous alkali aluminosilicate metal; (c) graphite or carbon black in the form of fine particles; or d) mixtures thereof, wherein said suspension has high storage stability in the absence of stabilizer.

Description

The present invention relates to a suspension having high storage stability comprising an aqueous silicate solution and a filler.

BACKGROUND OF THE INVENTION

Such a suspension is described, for example, in US-A-4,361,659. This suspension contains crystalline calcium carbonate and silica powder as filler. In order to obtain suitable stability, an alkali-resistant organic polymer is added to the suspension.

Organic chemicals are often undesirable in terms of environmental protection and health. Security can be. a major problem when used in equipment operating at higher temperatures, such as drying at higher temperatures. Furthermore, the suspensions stabilized by the organic stabilizer are very sensitive to small changes in composition. For example, with a small overdose of the stabilizing agent, they may become gels during storage. Suspensions stabilized by organic compounds are often unstable even at low dilution or at different ionic strengths of the aqueous phase.

US-A-4,403,059 discloses a composition based on an aqueous solution of an alkali metal silicate containing 10 to 40% by weight of an inorganic filler powder which has good stability using a zinc fatty acid soap containing 12 to 22 carbon atoms as a stabilizer. In the composition of this US patent application, it is difficult to define a specific amount of an organic stabilizer needed for optimal stability control without excessive viscosity growth.

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Furthermore, the use of stabilizers containing zinc soap and polymers limits the possibility of using such suspensions due to environmental and safety requirements.

The suspensions may also be stabilized with inorganic stabilizers, such as inorganic clays, with particles of about 0.1 microns in diameter, and these clays are also used as thickeners having swelling properties. These stabilizers may further interfere with the other ingredients used in the formulation.

Suspensions stabilized with inorganic stabilizers usually have a high viscosity due to the thickening properties of the stabilizer, which limits the usability as well as the amount of solids that can be added.

GB-A-2 058 818 discloses an aqueous spray coating adhesive composition comprising (i) an alkali metal silicate solution (ii) 1 to 10% by weight of a finely divided inorganic powder containing (mineralogically) more than 15% and (iii) finely divided silica. The silica is preferably present in the form of silicic acid. In this patent application, kaolinite clay is used as a filler / stabilizer. The total amount of finely divided filler is limited to a maximum of 10% by weight.

It is currently known how to prepare an aqueous silicate suspension containing a relatively large amount of a fine filler while maintaining sufficient storage stability in the absence of a stabilizer.

SUMMARY OF THE INVENTION

The present invention now provides a suspension having high storage stability comprising an aqueous silicate solution

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J 000000 00000 00 00 and a filler, wherein the suspension contains at least 20% by weight of silicate, the filler has a mean particle size of 0.8 to 15 µm and a specific gravity of less than 2.75 kg / l, the filler being selected from the group consisting of and b) amorphous inorganic material in the form of fine particles or fibers, which is relatively inert in an alkaline aqueous solution containing an alkali metal aluminosilicate, c) fine graphite or carbon black particles, or d) mixtures thereof, wherein said suspension has a high storage stability in the absence of a stabilizer. It is surprising that the suspension according to the invention has excellent stability at. storage in the absence of a stabilizer. Usually, the fine filler does not settle in the 24 cm high liquid column. The specific gravity of the filler is preferably less than 2.5 kg / l.

It should be noted that in the suspension of the present invention, the use of stabilizers is by no means excluded and in certain specific uses it may be advantageous to add a stabilizer, for example, to improve the stability of the suspension or the like.

The prior art aqueous silicate solutions are used in many applications where filling and binding properties are required. For example, leaking sewage pipes can be refurbished in the ground by pumping a concentrated aqueous silicate solution into a leaking sewage system. This silicate solution leaks out of the system into the ground space around the crack site. After some time, the silicate in the waste system is replaced by a hardener, which also leaks into the leakage area and neutralizes the silicate in the ground, thus sealing the leakage points. The silicate and hardener thus fill the space between the soil particles around the openings.

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Usually, hardeners are used in the form of relatively expensive esters of organic acids which are hydrolyzed / released to liberate the acid required to neutralize the silicate.

It is important for the environment and for economic reasons to minimize the amount of ester used (and hence the silicate to be neutralized).

The presence of a filler in the suspension of the present invention is advantageous because, for example, when used in the repair of a waste system, the filler may partially fill the spaces between the soil particles, thereby reducing the amount of silicate needed and hence the amount of ester needed. Furthermore, some of the pores in the ground will be blocked by the filler, thereby reducing the penetration of silicate and ester into the ground, and hence further reducing the amount of silicate and ester needed. Also, the solids content of the suspension is increased, further increasing the density and strength of the pore filling material in the ground, and consequently reducing the permeability of the layer around the permeability area in the waste system.

In silicate solutions used for repairing waste systems, the silica content is usually limited to a maximum of 33% by weight, which of course limits the amount of silica in the silica gel (dry solids content) that may be formed after the hardener has been added. This limited solids content has the most significant effect on the physical and mechanical properties of the gel that can be obtained, limits, density / strength, and also limits the achievable minimum permeability of surrounding material such as sand, earth or soil. Also, hydrolysis of the ester to the acid can be relatively slow and uncontrolled.

Zeolites are preferably used as the filler in the suspension of the present invention. Zeolites are crystalline aluminosilicates.

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Ο Most zeolites are known to be relatively inert to the environment. Examples of zeolites that are available or can be prepared in the form of fine particles are zeolite 4A, zeolite P, zeolite X and zeolite Y. Zeolite P is advantageous because it has a layered structure, is not rough and is relatively soft, also causes minor damage to the device .

It is possible to prepare a suspension according to the present invention containing synthetically produced zeolite P, which is further advantageous in that it does not contain carcinogenic crystalline silica (silica, crystallobalite) as in the case where an inorganic mineral filler is used. These crystalline silicas are known to be carcinogenic and can be expected to be banned or restricted globally.

It is preferred to use zeolite P prepared according to the process described in EP-A-0 384 070, which has a silicon to aluminum ratio not greater than 1.33 and a calcium binding capacity as defined in EP-A-0 384 070 of less than 150 mg CaO per g anhydrous aluminosilicate.

The filler may advantageously comprise fine particles or fibrous amorphous inorganic material that is relatively inert to the alkaline aqueous solution and contains amorphous alkali metal aluminosilicate. Too-amorphous products tend to overreact in an alkali silicate environment. It has been found that the exception is amorphous sodium aluminosilicate prepared by precipitation from a highly alkaline aluminate solution and a highly alkaline silicate solution.

A preferred example of this amorphous filler is of synthetic origin because trace amounts of crystalline silica are present in natural alkali aluminosilicates which limit its future use for the reasons set forth above. If synthetic alkali aluminosilicate is prepared • 9

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99 99 99 999 999 9 9 9 9 9 9 9 9 β 999999 99 9 99 9 9 9 9 knows from pure liquid raw materials (silicate and aluminate), does not contain crystalline silica.

The filler may be a mixture of the above zeolites, an amorphous inorganic material in the form of fibers or particles, graphite or carbon black.

The inorganic filler used in the suspension of the present invention preferably comprises a zeolite.

The maximum filler particle size is, of course, dependent upon the specific gravity of the filler, the shape of the filler, and the specific gravity of the liquid silicate, the molar ratio (SiO ₂ / M ₂ O) and the concentration of the alkali metal silicate in the silicate solution.

For highly porous particles with a very open structure, such as amorphous sodium aluminosilicate, the mean particle size may be 14.83 μπι, still giving a suspension of the desired stability. Preferably, however, the average filler particle size is 0.8 to 10 µm, preferably 0.8 to 5 µm, more preferably 0.8 to 4 µm, and most preferably 0.8 to 2 µm.

The filler content of the suspension has physical limits. Preferably, the filler content of the suspension is such that the suspension can be poured or pumped as required for a specific application. For other applications (eg bonding paper, wood, concrete or brick), more concentrated suspensions of higher viscosity are required. Preferably the filler content is 2 to 50% by weight, more preferably 10 to 40% by weight and even more preferably 10 to 30% by weight.

In the suspension of the present invention, the aqueous silicate solution is not particularly limited and may be selected from known silicate solutions depending on the requirements of the specific application. Typically, the silicate solution is an alkaline silicate solution.

I metal, i.e. sodium, potassium, lithium silicate or ammonium silicate solution or a mixture thereof.

According to the present invention, a SiO ₂ / M ₂ O molar ratio in silicate is used according to the amount determined for the specific silicate solution, wherein M is a specific alkali metal or ammonium ion (Na, K, Li, NH ₄ ).

The SiO ₂ / M ₂ O molar ratio of these soluble silicates may vary between 1.0 to 4.0 and may be higher for lithium silicate. All. the silicate solutions are alkaline but the alkalinity decreases with increasing molar ratio. Thus, silicate solutions with a higher molar ratio are safer to handle, which can be demonstrated by the following safety classification of standard silicate solutions available on the market.

Molar ratio Solution available on tr- European classification SiO2 / M2O hu as (safety)

1.0 Corrosive metasilicate

2.0 "Alkaline silicate highly irritating (or" alkaline water glass)

3,3 "Neutral silicate not classified as (or" neutral water hazardous glass)

Therefore, the preferred SiO ₂ / M ₂ O ratio for most applications is higher than 2.6 and more preferably 3.3 and higher for safety reasons. For these hardening applications, it is also advantageous to maximize the SiO ₂ content and consequently the SiO ₂ / M ₂ O ratio to minimize the amount of hardener needed for neutralization. Surprisingly, it has been found that a higher molar ratio is also more suitable for forming a more stable suspension.

The properties of the suspension are strongly influenced by the molar ratio of SiO ₂ / M ₂ O. Therefore, the molar ratio of SiO ₂ / M ₂ O in aqueous

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999 9 99 99999 99 99 silicate solution 1 to 4.5, preferably 2 to 4 and most preferably 2.6 to 4.

The silicate content of the suspension according to the invention is at least 20% by weight and in particular at least 25% by weight. Preferably, the silicate content is as high as possible.

The present invention further provides an adhesive composition comprising a suspension of the present invention. These adhesives can be used for all kinds of adhesive applications, such as gluing paper, wood, concrete, brick, paving, rubber, leather (eg shoes), glass, metal (eg aluminum foil), plywood, plaster and particle board and so on. further. In particular, it is possible to glue together materials with irregular surfaces which are usually difficult to glue, such as filter paper, wood or concrete. Furthermore, the adhesive is particularly suitable for bonding perlite, vermiculite, glass fibers, mineral fibers, mineral wool, for example in the thermal or acoustic insulation of covers, panels, slabs, shapes, inserts, spray coatings and the like. The suspension of the present invention causes a very fast bonding and dries relatively quickly to form a flexible bonding and significantly reduce dustiness.

The advantages of using the suspension of the present invention in the adhesive compositions are as follows: - No organic compound (including volatile solvents) is used. - It is not necessary to clean or dry the surfaces before using the silicate suspension as filler or adhesive, and (inorganic) adhesive or filler reduces the flammability of the material used.

Since there are no organic materials that are not unsafe in themselves, and these materials are bonded with the adhesive of the present invention (for example, paper, cardboard, wood, sand, ground, and the like), they can then be disposed of in a landfill.

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The SiO ₂ / M ₂ O molar ratio in the aqueous solution of silicate in the adhesive of the present invention wherein M is an alkali metal or ammonium is preferably. 2.8 to 4.2. A higher molar ratio usually results in viscous products. However, these viscous products may be used as adhesives and, if appropriate, may be diluted to reduce viscosity. The mean particle size is preferably less than 3 µm.

A preferred example of a suspension of the present invention which is suitable as an adhesive is a zeolite suspension of Zeocros CG180 from Crosfield (Eijsden, The Netherlands) using a 10 to 30 wt% slurry in neutral silicate containing 35 wt% silicate with a molar ratio 3.3 when the average particle size of the Zeocros CG180 is about 1 µm. When a small amount of this slurry is spread over a portion of the surface of the sheet of paper and then covered with another sheet of paper, it is found that immediate firm adhesion has occurred and that drying takes place under normal conditions at about 20 ° C for several minutes. Strong bonding between sheets of paper also occurs with filter paper, as with standard paper, and individual parts of the paper cannot be separated without tearing. When using the adhesive of the present invention, the flammability of the bonded portions of the paper is reduced, organic compounds are not used, and a better bond is achieved.

With the adhesives of the present invention, laminated paper, spirally wound laminated paper tubes, cardboard, corrugated cardboard, wallpaper, laminated wood, plywood, leather, such as shoe soles and building materials can be produced. When gluing bricks and shoe soles, it has been observed that when using a zeolite suspension of Zeocros CG180 with a higher zeolite content (e.g. 27%), a stronger bond is achieved and therefore this content is advantageous. Adhesives can also be used to bond powders or other particulate or fibrous materials to form larger agglomerates, e.g. production of structured construction ·· 4 44 ·· ··

4 «4 · 4 · 4 · 44 · · 4 · 4 4 - 4« 4 4 4 4 · · 444444 · 4 44 4 4 4 44 444 44 44 44 elements such as bricks, tiles and the like. This composition can also be used in the manufacture of pulp for the manufacture of paper products.

The adhesives of the present invention can also be used for joining stone, brick or concrete building materials in the construction of walls, houses, as well as in repairing shoes and shoe soles by gluing leather parts.

It has been found that in these adhesive applications, it is not necessary to add surfactants or hardeners as long as the material to be bonded is sufficiently porous to allow the adhesive to penetrate and allow the suspension to dry. However, if the evaporation of water present in the suspension is too slow or if water resistance is desired, it is advisable to add a surfactant. As a surfactant, it is preferable to use a cationic surfactant such as cetyltetraammonium chloride.

The present invention further provides a drilling fluid containing the suspension of the present invention. In drilling for oil wells, suspensions of various solids in the aqueous system are circulated through a drilled hole, which is called a drilling fluid or sludge. The main task of this liquid is to cool the drill head and remove debris.

The purpose of the solids used in the drilling fluid is to increase the density of the drilling fluid and penetrate the pores in the ground around the drilled hole, thereby blocking these pores and minimizing leakage of the drilling fluid to the environment. Practically, these solids present a problem as they can lead to settling that can occur during breaks in drilling, for example when adjusting length, drill pipe and so on. In the drilling area, silicates are already used to increase drilling fluid density and to facilitate debris removal.

A high drilling fluid density is necessary to avoid so-called ejection when a high pressure layer is formed.

However, the use of the suspension of the present invention as a drilling fluid has many other advantages. Easy and safe dosing of particles which are already in suspended form (not a powder) is achieved, which is safe to health and the environment (the liquid contains no crystalline silica or other toxic or environmentally hazardous components). Suspended particles can be more easily separated so that they are of the correct size for pore blockage in the ground. Two main components for drilling can be dosed simultaneously in the liquid. Since it is possible to easily adjust the average particle size, the risk of particle settling in the drilling fluid is eliminated.

For environmental reasons, drilling fluids that contain high levels of organic compounds used in the past are now being replaced by water drilling fluids that do not or practically do not contain organic compounds. In connection with this change there is a problem with the lubrication of the drill head, which has been solved in the past by adding organic lubricants that are currently not acceptable.

The use of a stable suspension containing graphite or carbon black provides a good solution to this lubrication problem associated with the use of aqueous drilling fluid where it is not practical to mix fine graphite or carbon black powder in a drilling fluid in wind or offshore drilling platforms.

The present invention further provides a channel repair fluid comprising the suspension of the present invention. As discussed above, the suspension of the invention can be used in channel repair fluids and has the following advantageous properties. The solids content of the silicate slurry used is te te.

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This is much higher than in the previously known suspensions, thereby better filling the space between the soil particles, thereby forming a denser and firmer sealing layer around the gap space, and this will extend the service life of the repaired part of the waste pipe. Furthermore, a lower permeability of the layer around the repaired part of the duct is achieved and thus the leakage of liquid from the sewer to the environment or groundwater into the sewer is further minimized. This results in better efficiency and less leakage of the slurry into the soil. This can be a very significant advantage in highly porous soils where such losses are substantial.

When using the Zeocros CG180, additional environmental protection is also achieved as it binds some heavy metals, mineral oxides and mineral dust. Thus, the impermeability to the waste liquid does not have to be 100%, and if small flows through, heavy metals can trap the amount of this liquid, named Zeocros CG180 zeolite, and penetrate the environment.

so they will prevent them

The same principle applied to refurbishment of the waste system can be applied to other systems in which holes or cracks are repaired, such as concrete, which can be used, for example, in floors in (chemical) factories and also in concrete tanks, protection of tanks containing chemicals and located inside concrete tanks. The system can also be used in road repairs where holes and cracks can be filled with suspension with hardener. For larger holes, filler such as sand may be added.

The present invention also provides a binder comprising the suspension of the present invention. Binder has many possible applications and of course we cannot list all of them. The suspension of the present invention can be used in joining particles during agglomeration and the like. Advantageous bonding properties can be used, for example, in shotcrete, in the production of roofing

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9 '9 9 toto This kryt kryt kryt kryt kryt kryt kryt u in kryt kryt kryt kryt kryt in kryt in in kryt kryt in kryt kryt in kryt in in in kryt kryt kryt kryt kryt binders. In this application, solids in powder form, for example ash powders and various fly ash, can be used in various construction applications.

The suspension of the present invention increases the density, hardness and impermeability of the products produced. In the case of cremated waste and fly ash, it will also contribute to reducing the exclusion of heavy metals contained in these materials. The slurry may also be used to bond dusty substances such as mineral dust to asbestos.

The present invention further provides waste fixation compositions comprising a suspension of the present invention. Certain waste fixation procedures have been developed. An impermeable wall and an impermeable floor may form around the landfill where the waste is stored. This wall and floor usually consists of a plastic layer and / or a solidified layer, for example concrete.

According to the present invention said wall and floor comprises a layer consisting of a solid and a silicate which is cured by neutralization and gelling.

Using the suspension of the present invention as a waste fixation material, the following results were achieved.

Since the suspension contains an increased amount of solids, a harder and denser and therefore less permeable layer is obtained which has better encapsulating properties and potentially longer shelf life of the encapsulating material. Leaching is almost avoided using the suspension of the present invention.

As mentioned above, the use of zeolite type P, for example zeolite Zeocros CG 180, will provide additional advantages because this zeo14 amines and ammonium ions,

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The present invention further provides fixation and hardening compositions for ground surfaces (e.g. sand, soil or clay) containing the suspension of the present invention. Surface fixation or hardening is used for road construction or harder bases, such as buildings and so on, and is also suitable for fixing clean sand surfaces, such as dunes and deserts,. that expand or move through the wind.

According to the present invention, the surfaces can be fixed and cured by impregnating these surfaces. (e.g. by spraying) a suspension of the invention. Curing can be accomplished by neutralizing with carbon dioxide in air and gelling. However, this is a very slow process and, alternatively, a hardener can be used, preferably based on amorphous silica.

The invention provides another alternative for concrete cementitious building compositions comprising the suspension of the present invention. In this application, the suspension according to the invention can be mixed with a hardener (preferably silica or amorphous metasilicate). In a preferred embodiment of this application, additional solids (e.g. sand) are also added to increase the strength of the solid obtained after curing and reduce the cost.

The present invention further provides a spray coating composition comprising the suspension of the present invention. Spray coatings are for example those described in GB-A 058 818.

The present invention further provides a paper filler comprising the suspension of the present invention. In particular, it has been found that type P zeolites with very small particles (about 1 μπι), such as. such as Zeocros CG180, are useful in the paper industry as a potential filler that has the optimum characteristics15 • 49

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999 99 99 99 performance in terms of opacity and print performance achieved compared to the best products on the market. For the paper industry, Zeocros CG 180 zeolite must be in suspended form and not in powder form.

Therefore, the suspensions of the present invention are very suitable for this purpose.

The present invention also relates to the use of the slurry-containing adhesive of the present invention for the preparation of cellulose-containing materials such as paper products, e.g. . For example, the adhesive may be used in a method of manufacturing tubes consisting of two or more layers of cardboard and / or paper, wherein the adhesive is applied to at least one surface of the layers, the spiral wound layers and the adhesive of the invention applied to said surfaces. By using an adhesive in the process of manufacturing tubes and drums, better hardness, better crush resistance and lower moisture content in the final tubes can be achieved compared to the organic adhesives used today (for example, dextrins or polyvinyl acetate (PVA)). Surprisingly, it is possible to increase the production rate compared to the adhesives used hitherto. Furthermore, the same adhesive may be used to adhere the outer layer of the tube, for example tissue paper, to other layers made of cardboard. According to the prior art, to adhere the thin paper layer to the outer carton layer on one side and to bond the layers

Cardboard on the other hand, using different adhesives.

The adhesive-coated paper material of the present invention has flame retardant properties. This is an important and important feature since the paper / cardboard products prepared using the adhesive of the present invention can be used at higher temperatures and are safe to use.

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during storage. In laminated paper products, the adhesive of the present invention may be placed as a layer between the paper layers such that the paper layer has said flame retardant properties.

The slurry of the present invention can be advantageously used as a fireproof coating of any kind of substrate, such as mentioned above.

In particular, the present invention also relates to the use of the adhesive comprising the suspension of the present invention as a binder for mineral wool or glass fibers.

Obviously, the above applications are not a complete list of possible uses and the compositions of the invention can be used in many other applications.

The suspensions of the present invention may be preferably cured with a hardener. The hardener preferably comprises amorphous silica or alternatively amorphous metal silicate such as aluminum silicate, magnesium silicate or calcium silicate.

In a preferred embodiment of the suspension of the present invention, a curing agent based on amorphous silica is used as the curing system.

Surprisingly, it has been found that amorphous silica (SiO ₂ ) provides an excellent inorganic hardener that can advantageously be used in combination with the silicate-based suspension of the present invention.

Amorphous silica is synthetically produced and is commercially available from several manufacturers, such as Crosfield, Warrington (UK) under the trade names Gasil, Lucilite, Microsil and so on. Synthetic amorphous silicas are produced by porn • fc • ··· • · · · · · ·······

by neutralizing the silicate solution, filtering and washing and drying the obtained silica.

The solubility (dissolution rate) of the amorphous silica obtained according to this process, in an alkaline solution, depends on the precipitation and drying conditions used in the production of the amorphous silica, as well as the dissolution temperature and the alkalinity of the solution used and can also be varied by these variables.

It has now surprisingly been found that the addition of finely divided amorphous silica does not give rise to a stable suspension at all. On the other hand, the silica in amorphous form slowly dissolves into the silicate, thus acting as an acid, neutralizing the silicate and thus causing the formation of a gel. This phenomenon occurs when a sufficient amount of amorphous silica is mixed with a pure silicate solution to form a gel, but also when a sufficient amount of amorphous silica is mixed with a suspension of the present invention. The gels obtained after mixing the amorphous silica with the suspension of the present invention have excellent density, hardness and minimum permeability.

It has therefore been found that amorphous silica is ideally hard, completely inorganic and absolutely safe in terms of safety and the environment. It further reduces flammability and increases the solids content after curing. A further advantage is that the suspension cured with amorphous silica forms a neutralized solid phase with excellent adhesive and filling properties that is very solid and practically insoluble in water.

It has been found that the cure rate of a zeolite suspension in a silicate solution, for example a suspension of the present invention, using amorphous silica can be influenced by the choice of amorphous silica and the amount of silica used. Use of higher velocity silicas with a higher velocity of 18 ° C. Leaving it in alkaline aqueous solutions increases hardening.

speed

It is therefore possible to control the cure rate by selecting the type of silica, the optimum concentration and the temperature, which can be done by one skilled in the art. The curing system may be mixed with the suspension shortly before use.

The use of silica as a hardener has several advantages, for example, further increases the solid thickener content, resulting in a stronger and less permeable phase. Its use is safe both for human health and for the environment, and it is also important that no organic substance is used.

Amorphous metal silicate can also be used as a hardener. This compound results in a change in the spatial arrangement of the silicate in the slurry by changing the molar ratio of the SiO ₂ / M ₂ O components. , calcium silicate or aluminum silicate.

It has been found that graphite or carbon black, which are known as ecologically acceptable lubricants, can be suspended in an aqueous silicate solution to form stable suspensions, the graphite particle content preferably being 1-50% by weight, more preferably 5-35%. % by weight.

A stable suspension is further prepared when the zeolite and graphite particles are suspended together in an aqueous silicate solution. The filler preferably comprises a mixture of fine P-type zeolite particles and graphite or carbon black, more preferably the respective filler comprises a P-type zeolite mixture sold by Crosfield under the trade name Zeocros CG 180 and graphite or carbon black.

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The present invention further provides a drilling fluid containing the suspension.

The present invention will be further illustrated by several examples.

These examples are not intended to limit the scope of the invention as defined by the appended claims. Unless otherwise indicated, all percentages are expressed as percent by weight.

DETAILED DESCRIPTION OF THE INVENTION

Used materials:

A. Trade name: Crystal 0070 (Crosfield Eijsden (NL)) Product: neutral sodium silicate solution

Dry solids content: 35.06%.

SiO ₂ content: 26.81%

Na ₂ content 0: 8.25%

Density (20 ° C): 1355 g / 1 Viscosity: 0.051 Pa.s

B. Product: alkaline sodium silicate solution

Content dry solids: 45% SiO ₂ content: 29,67% Contents Na ₂ 0: 15,33% Density (20 ° C): 1456 g / l Viscosity: 0.090 Pa.s

C. Type P zeolite in dry powder form

Trade name: Zeocros CG180 (Crosfield Eijsden) Dry solids content *): 90%

Particle size **): 0.7-3 pm Mean particle size **): 0.92 pm D50: 1.22 pm

Effective Density ***): 2480 g / L

D. Wet P zeolite (filter cake)

Dry solids content *): 41.3% · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · ·

0

Mean particle size **): 3.18 gm

DJO: 3.22 µm

E. 4A zeolite in dry powder form from Crosfield, Eijsden Trade name: Zeocros CG150

Dry solids content *): 80%

Mean particle size **): 2.75 μιυ D ₅₀ : 2.7 9 μυι

Effective Density ***): 2070 g / L

F. Magnesium silicate in dry powder form Product: Macrosorb M15 (Crosfield Eijsden)

Mean particle size *): 7.44 µm

D ₅₀ : 3.95 μυι

G. Powdered amorphous sodium aluminosilicate Prepared by precipitation from a solution of sodium aluminate and sodium silicate at 60 ° C, washing and drying.

Sample Code: CENAS 019 F Dry solids content: 73.3%

Mean particle size: 14.83 μυι D ₅₀ : 12.33 μπί

H. Alusil ET, a commercially available, synthetic aluminum silicate, manufactured and sold by Crosfield, Warrington UK.

Dry solids content: 90%

Mean Particle Size: Maximum 10.3 µg, using a Mastesizer

I. Talc Powder Commercially available substance

Dry solids content:> 93.5% (heated to 1000 ° C)

J. Graphite in powder form Commercially available substance

Dry solids content: 99.5% (heated to 120 ° C) Particle size: 99.5% wt. less than 50 μπί

K. Microcal ET

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Commercially available, synthetically prepared calcium silicate, manufactured and sold by Crosfield, Warrington, UK Dry solids content: 90%

Mean particle size: maximum 10.3 µm measured

Mastersizer

L. Lucilite

Commercially available, synthetically prepared amorphous silica (hydrogel), manufactured and sold by Crosfield, Warrington, UK

Dry solids content *): 34.78%

M. Gasil HP 250

Commercially available amorphous silica, synthetically manufactured and sold by Crosfield, Warrington, UK Dry solids content *): 93.47%

Mean particle size: 4.8-6.2 pm (Mastersizer)

N. Microsil ED

Commercially available amorphous silica, synthetically manufactured and sold by Crosfield, Warrington, UK Dry solids content *): 89.37%

O. Potassium silicate solution K53

Commercially available aqueous potassium silicate solution manufactured and sold by Crosfield, Warrington, UK

Dry solids content *): 32.25%

SiO ₂ / K ₂ O molar ratio: 3.9

P. Potassium silicate solution K120

Commercially available aqueous potassium silicate solution manufactured and sold by Crosfield, Warrington, UK

Dry solids content *): 53.26%

SiO ₂ / K ₂ O molar ratio: 2.2

Q. Stabifix Super

Commercially available amorphous silica, synthetically manufactured and sold by Crosfield, Warrington, UK

44

4 4 4

4 4 4

444 444 •

4

4 4 ·

4 4 4

5 · • ·

4

4

4 ·

444 · 4

Dry solids content *): 94.6%

Mean particle size: maximum 10.3 μπι (Mastersizer)

*) Measured by heating to 800 ° C for 30 minutes **) Measured by sedimentation technique using a Sedigraph Type 5100 from Micromeritics ***) Measured by immersion in water

Example 1

Preparation of a suspension of 9% zeolite type P with a mean particle size of 0.92 μη \ in a neutral silicate solution.

Place 450 g of neutral silicate solution (A) in a 600 ml glass beaker. With vigorous stirring, about 50 g of P-type zeolite powder (C) is added for about 5 minutes. Stirring is continued until the powdered zeolite is completely suspended (about 5 minutes). The suspension has the following characteristics:

Zeolite content (absolutely dry zeolite)

SiO ₂ content (in aqueous phase) *):

Content Na ₂ 0 (in aqueous phase) *):

Silicate content (absolutely dry:

Total solids content:

Total water content: Density (20 ° C): Viscosity **):

9.0% 24.13% 7.42%

31.55%

40.55% 59.45% 1420 g / L

D s ¹ Bye. with 99 0.117 152 0,099 233 0,095 358 0,088

Comment:

*) In all examples, the content of SiO ₂ and Na ₂ 0 in suspension includes only SiO ₂ and Na ₂ 0 in solution and does not include SiO ₂

3

00 ♦ ·· ·· ·· • 0 0 · · · 0 0 0 0 ·

0 00 · 0 0 0 0 0 0 0

0 0 ··· · · 0000 00 0 ·· ·· ·· ·· Neither Na ₂ O present in added solid (eg zeolite) **) (Dynamic) viscosity is measured using a commercially available device: CONTRAVES RHEOMAT 108

A portion of the suspension is transferred to a 500 ml glass cylinder (height 240 mm) and stored as such.

Storage stability is determined visually, tested to see if there is a noticeable phase separation at the top of the layer, and whether the bottom is thicker. Possible settling on the bottom is also determined by introducing a rod with a flat, extended surface on one side, which is carefully dipped to the bottom of the cylinder.

Results: '

Shelf life Phase separation Settling at the bottom of the cylinder (days) in the top layer

0 *) 0

0 0 negligible **) negligible **)

This suspension is considered stable.

Comment:

*) 0 means no sign of phase separation or settling has occurred **) Negligible means that only a trace («1%) of phase separation or settling has occurred

Examples 2 and 3

Preparation of a suspension of 18% and 27% zeolite P with a mean particle size of 0.92 µm in a neutral silicate solution

99

I · 9 9 9 9

99é · 99

9

9 9 9 · * ♦ ♦

9 9 9 •

In Examples 2 and 3, the same procedure was carried out using the same zeolite powder and the same 'silicate solution' as in Example 1, using the following amounts:

Example 2 Example 3 Silicate solution (g) 400 350 Type P zeolite (g) 100 150 The suspension obtained has the following properties: Ex. 2 Ex. 3 Content of zeolites (abs. Dry zeolites) (%): 18.0 27.0 SiO ₂ content (in aqueous phase) (%): 21.45 18.77 Content Na ₂ 0 (in aqueous phase) (%): 6.6 5.77 Silicate content (absolutely dry) (%): 28.05 24.54 Total solids content (%): 46.05 51,54 Total water content (%): 53.95 48.46 Density (20 ° C) (g / l): 1470 1550 Viscosity: Pa.s at D s ¹ 17.7 ! 3,470 2 7.2 2,480 41.7 1,790 64 0.366 1,331 99 0.297 0,973 150 0.254 0.730 232 0.317 0.594 358 0.186 Suspension stability: The stability of the suspension is determined as in example 1 in 25

glass cylinder of the same shape and dimensions. Results:

Example 2 Example 3

Warehouse-Division. Bottom Layer Stages Bottom Layer Stages (Days) in the Top Roller Layer in the Top Roller Layer '0 0 0 0

O

O

O

About negligible negligible

0 negligible 0 negligible 0

This suspension also has excellent stability. From these results, it was judged that 5 days of storage was sufficient to determine the stability of the suspension.

Example 4

Preparation of a suspension of both 14.6 and Type 4 zeolite with a mean particle size of 3.18 microns in a neutral silicate solution

The procedure was carried out in the same manner as described in Example 1 using an equally sized glass beaker for preparation and the same glass cylinder to determine suspension stability. The experiment was performed twice because the stability test showed irregularities.

Starting substances:

Neutral silicate solution (Compound A) 400 g

Zeolite filter cake (fabric D) 218 g Suspension obtained: Zeolite content (abs. Dry) 14.6% SiO ₂ content (in aqueous phase) 17,35% Contents Na ₂ 0 (in aqueous phase) 5.34% Silicate content (abs. Dry) 22,69% Total dry solids content 37,29% Total water content 62,71% Density (20 ° C) 1370 g / l Viscosity: D s' ¹ Bye. with 358 0.019 Stability Days Bottom sediment (opposite) Phase distribution at the top

ml (ml) ml 8 ml o

·················

* • »» · · * * * *

105 ml 110 ml

O ml

100 ml

The suspension is not stable, but the interface is formed, it has good stability within 1 day. No sediment is formed at the bottom and re-slurrying requires minimal agitation or shaking. Stability may be acceptable for some applications where a relatively short time interval between slurry production and use is used.

Example 5

Preparation of a 14.6% zeolite P-type suspension with an average particle size of 0.92 µm in a neutral silicate solution

The procedure was as in Example 1 using a glass beaker of the same size for preparation and the same glass cylinder to determine the stability of the suspension.

In this Example 5, a suspension of exactly the same composition as in Example 4 was prepared. For this purpose, 100 g of zeolite type P (substance C) was used after addition of 118 g of demineralized water and exactly the same dry solids content was obtained. Compound F used in Example 4.

400 g of neutral silicate (substance A) is also used. Composition and properties of suspension:

Same as Example 4. The difference from Example 4 is only in the zeolite P particle size.

Stability:

Days Sediment at the bottom

0

0

0

Phase distribution in the upper layer negligible negligible negligible

This suspension is stable, demonstrating the effect of particle size.

····················

9 9 9 9 ·

9 9 9 9 9

99 ··· ···

Example 6

Preparation of a suspension of 16% zeolite 4A with a mean particle size of 2.75 µm in a neutral silicate solution

Proceed in the same manner as above, using A (400 g) and E (100 g).

Resource Properties:

Zeolite content (abs. dry) 16.0 Q., O SiO ₂ content (in water phase) 21.45 % Content Na ₂ 0 (ve water phase) 6.6% Silicate content (abs. Dry) 2 8.05 % Total water 55.95 % Density (20 ° C) 1448 g / ml Viscosity: D s' ¹ Bye. with 64.6 0.165 99 0.144 152 0.125 233 0,118

Stability:

Days Sediment on the bottom Separation of the phases in the upper layer

1 0 30 ml 2 0 40 ml 5 ' 0 50 ml

Examples 7 and 8

Zeolite suspension type

P in alkaline silicate solution

Proceed as above and use the following substances and amounts:

Example # Silicate Mass From eo1i t solution substance wt. content (% abs <g) (G) dry) 7 (B) 400 C 100 ALIGN! 18.0

44 44 44 44

44 4 44 4 4 48 4

4445 44 4 4 44 4

44 44 44 449444

443 4 4 4 4 4

4444 44 444 44 44 44

Β 400 D, 218 14.6

Examples 9 and 10

A suspension of type P zeolite in a dilute alkaline solution of quartzite

The procedure was the same as in the previous examples using the following materials. The silicate (substance B) is preceded

using diluted with water ( 2: 1) content dry firmly substances 30 Used by: following amount: Example # Hm. diluted kře- Zeolite mičitan .(G) substance wt. content .(% (G) abs. dry) 9 400 C 100 ALIGN! 18.0 10 400 D 218 14.6

Characteristics of suspensions 7 to 10:

Example number 7 8 9 10 Stř. zeolite particle size 0.92 3.18 0.92 3.18 (pm) Zeolite content (% by weight) (abs. dry) 18.00 14.6 18.0 14.6 SiO ₂ content (% by weight) (in aqueous 23.74 19.2 15.82 12.8 stage) Content Na ₂ 0 (wt.%) 12.26 9.9 8.18 6.6 Dry solids content 3 6,00 2 9.1 24.0 '19, 4 Chitanate (% w / w) Total solids content substances (%) 54.00 43.7 42.0 34.0 wt.) Total water content (% wt.) 46,00 56.3 58 66 Density (g / 1) 1670 14 8 8 1452 1346 Viscosity of suspensions (Pa.s): Viscosity at D s ¹ Example number 17.7 27.62 41.7 64 233 358 7 1,840 1,800 1,790 1,770 8 0,048 '

0.028 • · • ·

················ * 9 9 • ♦ 9

9999 99

9 9

10 *)

*) The viscosity of the composition of Example 10 could not be measured because it was less than 0.007 Pa.s.

Stability of suspensions: Sediments Example 7 8 9 10 Days 1 0 0 0 0 4 0 0 0 0 5 0 0 0 0 According to of Example 7 a 8 se gains

Phase distribution

7 8 9 10 0 zanedb. 4 ml 3 6 ml 0 zanedb. 22 ml 148 ml 0 zanedb. 22 ml 152 ml suspension with good stability,

whereas the sample tested in Example 9 has boundary stability and the sample of Example 10 has unacceptable stability.

These examples show that the stability of the suspensions is strongly dependent on the concentration of the silicate solution used. Higher silicate concentrations are preferred.

Comparative Example 11 to 13

A suspension of Type P zeolite in a dilute neutral solution of silica

These suspensions are prepared according to the same procedure as described above

above, using 400 g of solution silicate (lath at various dilutions with water; and 100 g of substance C. Example No. Dilution Zeolite P Substance A: Water Substance 11 2: 1 C 12 1: 1 C 13 1: 2 C Composition, suspensions 11 to 13: Example number 11 12 13 Mean particle size of zeolite (pm) Zeolite content (% by weight) (abs. Dry) 18 18 18 SiO ₂ content (% by weight) (in, aqueous phase) 14.3 10.72 7.15

99 '

• 9 99

9

999 999 • 9 99

999

Content (Na ₂ O) (% by weight) 4.4 3.3 2.2 Dry silicate content (% by weight) 1.8,7. 14.02 9.35 Total obsah pev. substances (% by weight) 36.7 32.02 27.35 Total water content (%) wt.) 63.3 67.98 72.65 Stability: Sediments Distribution phase (ml) Example 11 12 13 11 12 13 Days 1 0 0 0 38 70 4 0 0 0 80 104 122 5 0 0 0 65 108 125

Comparative example

Suspensions of the zeolite type

P in a concentrated solution of sodium chloride in water

Pure sodium chloride is dissolved in demineralized water and a maximum concentration of 26.31% by weight is reached. The same procedure as in the previous examples was followed, using a type P zeolite having a mean particle size of 0.92 gm (Compound C) and 400 g of this concentrated sodium chloride solution.

Suspension composition:

Zeolite content (abs. dry) (% by weight): • 18 Sodium chloride content (% by weight): 21 Total content solids (% by weight): 39 Water content (%) wt.): 61 Density (g / 1): 1290 Viscosity D s' ¹ : 233 Passport: 0.050

Stability:

Days Sediment Phase distribution ft · ftft · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · Ft ft ft ft ft ft ft ft ft ft ft ft ft ft · · Ftft ftft ftft

O 66

O 75

This suspension does not have good stability. Since the concentration of sodium chloride is already high for an aqueous salt solution, it follows that other salt solutions are not suitable and that the silicate has a unique position due to the stability of small suspensions. particles of an inorganic crystalline substance dispersed therein.

Comparative example

Preparation of a suspension of magnesium silicate having a mean particle size of 7.44 µm in a neutral silicate solution

Proceed in the same manner as in the previous examples, using 100 g of magnesium silicate (F) and 400 g of neutral silicate solution (F) to obtain a suspension containing 15.6% by weight of magnesium silicate (abs. Dry). Dry solids content 78%.

The suspension obtained was not stable at all. The amorphous magnesium silicate powder begins to react with the silicate within hours. This produces a gel. It follows that amorphous magnesium silicate can also be used as a silicate hardener, preferably for suspensions of crystalline aluminosilicates, for example zeolite in the silicate solutions of the present invention.

Example 16

Preparation of a suspension of amorphous sodium aluminosilicate with a mean particle size of 14.83 µm in a neutral silicate solution

Proceed in the same way as above using 153.74 g of sodium aluminosilicate (substance G) and 500 g of neutral fcfc fcfc fcfc fcfc fcfc fcfc fcfc fcfc A solution of a silicate solution (Compound A) to form a suspension containing 17.23% by weight of amorphous sodium aluminosilicate.

Composition and characteristics of the suspension:

Obs. amorph. sodium aluminosilicate (abs. dry): 17.23%

SiO ₂ content (in aqueous phase): 20.51%

Na ₂ O content (in aqueous phase): 6.31%.

Silicate content (in the aqueous phase): 26.81%

Total water content: 55.96%

Density: 1450 g / l

Calculated silicate content in the liquid phase, irrespective of possible absorption by amorphous sodium aluminosilicate:

Obsah abs. Dry silicate in liquid phase: 32.29% Stability:

Days Sediment Phase distribution

0 0

0 3 6 ml

0 118 ml

Surprisingly, the suspension stability with respect to settling is marginal, although the mean particle size is 14.83 μπι.

This phenomenon is explained on the assumption that the physical structure of this amorphous sodium aluminosilicate is more open and has a more porous content.

Obviously not all amorphous silicates react with the silicate solution because the amorphous aluminosilicate used in this example is relatively inert. A possible explanation may be that the raw materials used to prepare other more reactive amorphous silicates were all aluminum, calcium and magnesium metal salts reacting with sodium silicate at a relatively low pH (less than pH = 9), while relatively inert amorphous sodium aluminosilicate was obtained by reaction of a solution. highly alkaline sodium aluminate with a sodium silicate solution under highly alkaline conditions at a pH greater than 12.

4 4

4 4 4

444 444

Apr '44 ·· ♦ · • · * • ·· *

4 4

4 4

9444 44

444 ··.

··

4

4 • · ··

Summary of Results from Examples 1 to 14

Ex. C. Type Zeolite Conc. Silicate / NaOl *) Conc. salts Conc. salts Stabil zeolite Vel. of particles zeol. v susp. v susp. susp. Avg. D50 (abš.s.) Type Conc. in use (% wt.) (% wt.) (pm) (pm) (% wt.) OUR mol. (% wt.) 1 P 0.92 1,22 9 N 35.06 31.55 40.55 + 2 P 0.92 1,22 18 N 35.06 28.05 46.05 3 P 0.92 1,22 27 Mar: N 35.06 24.54 51,54 + 4 P 3.18 3.22 14, S N 35.06 22.69 37.29 +/- 5 P O, '92 1,22 14.6 N 35.06 22.69 37.29 + 6 4A 2.75 2.79 16 N 35.06 28.05 44.05 +/- 7 P 0.92 1,22 18 AND 45,00 36,00 54.00 + 3 P 3.13 3.22 14.6 AND 45,00 29.10 43; 70 . + 9 P 0.92 1,22 18 AND 30,00 24,00 42,00 +/- 10 P 3.18 3.22 14.6 AND 30,00 19.40 34,00 IN- 11 P 0.92 1, 22 18 N 23.37 18.7 36, 7 +/- 12 P 0.92 1, 22 18 N 17.53 14.02 32.02 - 13 P 0.92 1,22 18 N 11.69 9.35 27.35 - 14 p 0.92 1,22 18 WITH 26.31 21 39 +/- *) N = neutral silicate; A = alkaline silicate ; WITH

sodium chloride solution

This table demonstrates the relationship between stability and salt concentration. It is probably more likely to assume that stability is related to the concentration of salt (silicate or sodium chloride) in the liquid phase of the suspension. However, the table above represents the salt content of the suspension including the solid phase.

In the following table the salt concentration is corrected for content

solids (zeolite) and therefore represents : calculated content salts in liquid (aqueous) phase suspension. Ex. C. Type of zeolite Conc. zeolite (wt%) Center, Size Type Silica- of zeolite tan / NaCl particles (pm) Conc. salts in liquid phase (% wt.) Stability suspension 1 P 9 0.92 N 34.67 . + 2 P 18 0.92 N- 34.21 + 3 P 27 Mar: 0.92 M 33.62 + 4 P 14.6 3.18 N 26.57 +/- 5 P 14.6 0.92 N 26.57 + 6 4A 16 2.75 N 33.31. +/- 7 P 18 0.92 AND 43.90 + WITH P 14.6 3.18 AND 34.07 + 9. P 18 0,92 | AND 29.27 +/- 10 P 14.6 3.18 AND 22.72 +/- 11 P 18 ' 0.92 N 22.80 +/-

• • • • •

34 • · • · • ·· · • · · • · ·· ··· ··· • · • · ··· · • • «· 12 P 18 0,92, N 17.10 - 13 P 18 0,92 _? N 11.40 - 14 P 18 0,92 WITH 25.61 + / - This table shows the following: • Stable a zeolite suspension cannot be prepared if is over trace salt in the liquid phase of the suspension lower than about 20% wt companies, when it is medium size of particles zeolite 0.9 μιτι.

The concentration of sodium chloride (26.3%) in the solution used in Example 14 is close to the saturation point. Therefore, sodium chloride is not suitable as a salt as such.

Alkaline silicate is suitable because it can reach a concentration of about 50% by weight in aqueous solution).

Comparative example 17

Preparation of a slurry of 20% talc powder in a neutral silicate solution

Proceed as above, using 400 g of neutral sodium silicate solution (Compound A) and 100 g of talc powder (Compound I) to form a slurry containing 20% by weight of talc powder.

The suspension obtained has a density of 1280 g / l.

Product Rating:

It has been found that the talc powder appears to contain too much air, which is difficult to remove under normal mixing conditions. Therefore, it was not possible to obtain a homogeneous suspension under this less intensive stirring.

Example 18

Preparation of a suspension of 20 i graphite powder in neutral sodium silicate solution

Proceed in the same manner as above using 400 g of neutral sodium silicate solution (A) and 100 g of graphite powder (J) to form a suspension containing 20% of graphite powder.

The prepared suspension has a density of 1232 g / l.

The suspension is stable, although after several days of storage it can be observed that some (traces) of graphite accumulate on the surface, which is probably also due to the fact that it contains air.

Comparative Examples 19 and 20

Preparation of a suspension of 15% and 18% amorphous aluminum silicate powder in neutral sodium silicate solution

Proceed in the same manner as above to give a slurry containing 15% by weight (ex. 19) and 18% by weight (ex. 20) of aluminum silicate powder.

Folders used:

neutral sodium silicate solution (AND) amorphous aluminum silicate (H) Amounts used: Example 19 Example 20 Neutral Silicate Solution (g) 416.7 400 Aluminum Silicate (g) 83.3 100 The suspension obtained in Example 19 has density 1408 g / l. Both the suspensions are stable for about one day. Then it will gelling; Amorphous aluminum silicate apparently not to the solution

silicate chemically inert.

999 999 • 9 · 9 · 9 · 9

9

99 9 9-9

Example 21

Preparation of a suspension of 18% zeolite, after medium particle size 0.92 µm, in a solution of potassium silicates with a SiO ₂ / K ₂ O 3.9 molar ratio

Following the same procedure as above, a suspension containing 18% by weight of zeolite P was obtained.

Folders used:

Potassium silicate solution (0) (g) 400

Type P (C) (g) zeolite powder

The suspension obtained contains 18% by weight of zeolite (dry) and has a density of 1388 g / l.

The suspension is completely stable.

Example 22

Preparation of a suspension of 18% zeolite type P with a mean particle size of 0.92 µm in a solution of potassium silicates with a molar ratio SiO ₂ / K ₂ 0 2.2

Proceed in the same manner as described above to give a suspension containing 18% by weight of zeolite P type.

Folders used:

The potassium silicate solution (P) is first diluted with demineralised water to a dry solids content of 40%. It shall apply

400 g of this dilute potassium silicate solution and 100 g of zeolite powder (C).

The suspension obtained has a zeolite (dry) content of 18% by weight and a density of 1512 g / l.

The suspension is also stable.

9 te te te te te te te te te te te te te te te te te te te te te te te te te te te te te te te te te te te te te te te te te te te te te te te te te te te te te te te te te te te te te te te te te te te te te te te te te te te te te te te te te te te te te te te te te te te te te

Comparative example

Preparation of a suspension in a neutral solution of% amorphous calcium silicate silicate

Proceed in the same manner as above to obtain a slurry containing 18% calcium silicate powder (K) in a neutral silicate solution (A) '.

Use 100 g of calcium silicate (K) and 400 g of sodium silicate solution (A).

The suspension has a density of 1444 g / l.

The suspension begins to gel after 1 day.

Example 24

Filter paper bond test

Used material:

pieces of laboratory filter paper the substance of Example 2 (18% P zeolite in neutral silicate solution

A few drops of slurry are applied to the surface of a single piece of filter paper. A second piece of filter paper is placed on the first and the filter papers are pressed together by hand to spread the suspension over a total area of about 2 cm ² .

Immediate gluing occurs and the suspension dries sufficiently within 5 minutes and then it is not possible to separate the papers without tearing.

Example 25

Test of bonding of office paper

The same test was performed as in Example 24 using sheets of standard commercially available writing pad paper.

• · · φ · φ · · • · • · • · • · • · • · • · • · · ·

ΦΦΦ · φφ φφφ φφ φφ φφ

The same observation was made: good adhesion and strong bonding after 5 minutes, during which it was not possible to separate the papers without tearing them. Fast and excellent bonding was achieved.

Example 26

Production of multilayer cardboard tubes

Using a spiral winch containing paper pulp and a one-sided cascade of adhesive application system, three tube types are produced at a variable paper feed rate of 17 to 60 m / min.

Type 1: Outer diameter 79 mm, inner diameter 70 mm (wall thickness 4.5 mm, 8-layer standard cardboard Schrenz (Germany), COBB value higher than 200 gsm, 0.5-0.6 mm, with outer layer of thin white paper). Cut off 1,7. m, cutting time 10-15

with.

Type 2: 75 mm outer diameter, 70 mm inner diameter (2.4 mm wall thickness, four-layer Schrenz standard cardboard, COBB value greater than 200 gsm, 0.5-0.6 mm, with a thin brown paper outer layer). Cut off 2 m.

Type 3: 76 mm outer diameter, 70 mm inner diameter (2.4 mm wall thickness, five-layer standard high quality carton, COBB value greater than 30 gsm, without outer layer).

Adhesive composition: 1000 kg of sodium silicate (M _H 2950, 39.50 Be (20 ° C)). With the zeolite A24, the viscosity was adjusted to 120 '(DIN bulge B funnel 4 mm), which in this case was 600 kg of A24 (23.02% by weight). The final density of the mixture is 1520 kg / m ³ . The material was stirred in a 100 L drum until the zeolite was thoroughly dispersed. (visual inspection). The composition was made 5 days before the test. The prepared suspension was stored at room temperature (17 ° C) for 4 days and mixed again the day before the test. The application temperature was 21 ° C. The temperature of the application was 21 ° C.

• · · · · · · · · · · · · ·

Test results:

All types of pipes can be manufactured without any problems. No glue problems have been observed with the type 3 tube encountered with prior art formulations. The paper feed speed can increase up to the maximum speed without the paper slipping. The glue application was controlled by the weight of the paper and varied ad 8 to 20% without slipping. The tubes were dried at 105 ° C.

Using 20% glue (based on paper weight), the 31cm tube weight immediately after production was 297.48g. After four days of drying at room temperature, the weight was reduced to 241.83g (6.07% weight loss). In a similar experiment using 8% glue (based on the weight of the paper), there was a 3.50% weight loss.

Compared to prior art adhesives (PVA from Scholten Lijmen), the hardness and hence the maximum compressive strength of the tubes has improved by more than 10%. It also improves strength at smaller pipe deformations and remains constant at higher deformations (measured up to 9 mm at 100 mm outside diameter).

Cardboard tubes made with PVA or dextrin as adhesives are easily ignited by a medium-flame gas burner. They will burn and the cardboard will burn completely. However, the same cardboard tubes according to the invention do not ignite even at the maximum temperature of the gas burner. When the burning fire is removed it goes out.

Example 27

Gluing test of two pieces of wood

Used materials:

suspension according to example 2 0 · ···

0 00 00 00 0 0 · 0 0 • 0 0 · kusy kusy kusy kusy kusy kusy kusy kusy kusy kusy kusy kusy kusy kusy kusy kusy kusy kusy kusy kusy kusy kusy surface with the same dimensions (18 mm x 10 mm x 64 mm)

A very thin layer is applied to one piece of wood to cover just one surface of the wood (18 mm x 64 mm). The pieces of wood are then immediately pressed by hand together and left for about 1 minute.

Then, a very firm bonding occurs. After about 10 minutes it is extremely difficult to separate the pieces. Great strength is needed, although it has not yet dried completely. Two. the pieces can be glued together again without applying the adhesive. After another 10 minutes it was even more difficult to separate the pieces. Great force had to be exerted from the corner.

The experiment was repeated using the same pieces of wood (using opposite sides) and using the same procedure. Bond strength was tested after 24 hours. The strong man was then unable to separate the pieces by hand.

Later, the glued pieces of wood were placed in a 0.6 L glass container, the container was filled with water, and it was tested whether wetting would adversely affect the strength of the joint.

It was still not possible to separate the two pieces of wood after one hour of water. After 5 hours it was again possible from. cut pieces of wood apart. From this test it is apparent that a sufficiently stable bond is achieved for normal use, when drying under atmospheric conditions without the use of a hardener. However, when two pieces are glued together with this suspension in contact with water, it is preferred that a silicate neutralizing binder is used to obtain an insoluble adhesive. A preferred binder is amorphous silica.

Thus, the adhesive of the present invention provides an extremely good wood gluing system.

9 • «9 9

9 9 9

999 999

Advantages:

Wood surface does not need to be cleaned beforehand The wood surface does not have to be smooth

The wood surface can be wet / damp and does not need to be dried - No organic substances or solvents are used

Examples 28 and 29

Test of bonding bricks that have a very rough surface

Used materials:

bricks of very rough surface type, which are commonly used for building interior walls of houses, for double exterior walls or for industrial buildings. The brick surface contains grains protruding about 2 mm above the surface.

Brick dimensions: 9.8 cm x 21 cm x 5 cm.

The suspension of Example 2 for Example 28.

The suspension of Example 3 for Example 29.

A layer of approx. 2 mm of suspension and a second brick is immediately placed on this surface with the suspension applied.

After 5 minutes, the brick of Example 29 lying on top (upper brick) can be lifted and the lower brick remains glued to it. This did not occur with the bricks of the glued slurries of Example 2 in Example 28 when the lower brick fell. Since the suspension was not yet dry, the bricks could be stuck together again. After about 30 minutes, the bricks of the example were also. 28 sufficiently glued so that the lower brick no longer fell off. After several hours, the bond in Example 29 was so tight that no separation occurred even when maximum manual force was applied.

In Example 28, using the suspension of Example 2 containing 18% zeolite P, it was observed that there was an apparent shrinkage of the suspension between the bricks, while in Example 29, when using a content of &lt; 99 &gt;

98 • 9 9 9

9 9 9

999 98 9 • 9

With the more concentrated suspension of Example 3 of 27%, this shrinkage was minimal.

zeolite P

These tests show that the zeolite suspensions in the silicate solution of the present invention provide excellent adhesion when joining bricks, and that with increasing zeolite concentration the results improve.

Example 30

Repair leather shoe soles by gluing using a silicate suspension

Used materials:

The suspension of Example 3, i. a suspension of zeolite type P, Zeocros CG 180 in neutral silicate containing 27% by weight of zeolite.

The suspension of Example 3 is used to repair shoes whose sole has peeled off during long wear.

The used shoe and the used sole that separated during wear were not cleaned, the surface remained dirty (containing ground). The correction was as follows:

The very thin slurry layer of Example 3 was applied with a spatula to the leather sole. The sole pressed his hand against the shoe. Excess suspension was squeezed out of the space between the shoe and the sole with a cloth. The sole was pressed to the shoe for 10 minutes and was then well adhered to the shoe.

After 24 hours, the sole was well adhered to the shoe, and after 3 weeks of wear there was no evidence of peeling.

Example 31

Addition of amorphous silicate to neutral solution, sodium silicate • 4 4 4 4 4 4 4 4 4 4 4 4 4 44 4,444 4 ♦ 44,444 4 4

4444 44 444 44 44 44

Used materials:

Material number Content dry solid % by weight of substance Neutral sodium silicate solution AND 35.06 Amorphous silica: Lucilite L ' 34.78 Amorphous silica: Gasil HP250 M 93.49 Amorphous silica: Microsil ED . N. 8 9.37 Amorphous silica: Stabifix Super Q  94.6

Method:

These silicas were suspended in the neutral silica solution of Example 1.

A series of suspensions were formed having different silicon dioxide contents in the silicate solution.

It was not possible to prepare suspensions by adding more than about 15% by weight of dry silica.

Prepared suspensions and their storage behavior:

(SiO _second and sodium silicate in the suspension are expressed

in absolutely dry condition) Material I.e M N 0 Sample number IF L2 L3 L4 Ml M2 M3 NI N2 N3 Ol 02 / 03 / SiO ₂ (wt.%) 4.4 7.8 10.5 12, 7 4.7 9 12, 9 4, 7 9 12,8 4.7 9 12.9 Silicate (% h) 31 27 Mar: 25 22nd 33. 32 30 33 32 30 33 32 30 Gel time (h) <1/2 <1/2 <1/2 <3/4 15 Dec <15 <15 > 4 8 24 20 May 15 Dec <15 «15 Gel type, 1 day *) with h h mh 1 with with 1 with with 1 WITH h Gel type, 2 days with h h h 1 with with 1 with h 1 WITH h TYPE OF GEL. 4 days with h h h 1 h h with h h 1 h h Gel appearance *) t t t O - 9 9 - - t 9 9 9 *) After 1 day se gel tested visually a after 1, 2 and 4 days se strength tested by hand indentation sticks to gel and provided se

necessary pressure.

The following symbols were used to characterize the gel:

= liquid; s = very soft; mh = medium and h = hard, t = translucent; g = gray; o = opaque

9 9

9 99

9 9

9 9

9999 99

99 9 9 • 9 9 9 9

9 9 9 9 9 9 999 999 • 9 9 9

99 99 99

Summary:

L (Lucilite) is a hydrogel and is the most soluble and not more reactive and produces the hardest and most suitable gel. Other silicas also show different gelling properties. It has been observed that with increasing silica content, the gelling is more effective and the gel obtained is harder.

It can be assumed that the process of dissolving the silica for material L, which is highly reactive, ends within one day, while for other silicas the reaction takes a longer time.

Sample L4 shows that, with an apparent excess of silica, the gel becomes opaque and softens again. From this result, it can be concluded that to achieve maximum hardness, there is an optimum level of added silica, which is about 10% silica. I.e. 40% by weight relative to the neutral silicate (Total effective molar ratio SiO ₂ / Na ₂ O is then 4.7).

Examples 32, 33 and 34

Add amorphous silica to neutral sodium silicate solution at 50 ° C and 80 ° C

To demonstrate the effect of temperature on gelling time, a slurry of silica in neutral sodium silicate solution was prepared at 50 ° C and at 80 ° C.

Method:

To a mortar preheated to 50 ° C for Example 31 and 80 ° C for Example 33, a neutral sodium silicate solution (substance A) is added and heated to the same temperature, then silica is added, briefly triturated to form a thick mixture.

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The suspension obtained is quickly transferred into a glass beaker containing a

250 ml and kept at a temperature 50 ° C for Example 31 a 80 ° C for example 33 in a water bath. Used materials: Example number 32 *) 33 **) 34 **) Fabric (silicate) AND AND AND Silicate solution (g) 100 ALIGN! 100 ALIGN! 10 0 Silicon dioxide no. L M M Silica (as such) (g) 28.75 10.7 10.7 Storage temperature ⁵⁰ 50 80 Beginning of gel (min) *** 2 10 3 *) Example 31 is based on the same raw materials and has the same composition as sample L2 in Example 30 which tested at room temperature (about 20 ° C) ° C). Gelování sample L2 at temperature room started after about 30 minutes. **) Examples 32 and 33 are based on the same raw materials and have the same composition as sample M2 z of Example 30, which is

also tested at room temperature. The gelling of the sample M2 at 20 ° C started very slowly and the real start time cannot be defined (after several hours).

***) Determination of gelling at 50 ° C and 80 ° C:

The gelling was observed visually and the force required to penetrate the glass rod into the gel suspension was regularly determined.

Summary:

1. Increasing the storage temperature (or "curing") will reduce the time required for gelling or solidification (or: "curing or" curing).

2. The addition of amorphous silica effectively causes gelling (or "curing or" curing) of the silicate solution.

3. The curing of the silicate solution using amorphous silica also causes the hardened product to be less. Ftft.

soluble in water, forming a more permanent &quot; cure &quot; even in contact with water.

Examples 35 to 39

Addition of amorphous silica to suspensions of zeolite P in neutral silicate solution

Method:

A slurry of 15% by weight zeolite in neutral sodium silicate solution was prepared according to the procedure described in Example 1 using the same glass beaker of the following composition: Zeolite in Silicate Suspension:

Silicate solution (Compound A) (g): 500

Zeolite powder (Compound C) (g): 100

Zeolite content (abs. Dry) (% by weight):

This slurry was divided into 120 grams to which amorphous silica was added at room temperature in a mortar.

After intensive spreading in a mortar, the samples are placed in small glass beakers and the gelling process is observed.

The following tests were performed:

Example number 35 36 37 38 39 Zeolite suspension (g) · 120 120 12 0 120 120 Amorphous silica: material number L L L M M weight (as such) (g) 14.4 28.8 43.1 5.37 10.7 Final composition of the suspension Silicate (dry) (% wt.) 26.1 23.6 21.5 28.0 26.0 Zeolite (dry) (wt.%) 13.4 12.1 11.0 14.4 13.8 Silica (dry) (% wt.) 3.7 6.7 9.2 4.0 7.7 Water content (% wt.) 56.8 57.6 58.3 5 3, '6 51.7 Geling *): start of gelling (min.) 30 30 30 after 1 day s.g. G h s.g. h after 2 days s „g. h h s.g. h

after 3 days • fcfc • fcfcfc · fc · fcfc · fcfc

s.g. h h

• fcfcfcfcfcfcfcfcfc

s.g. 'h

*) Geling is described as: s.g hard.

soft gel; g = gel; h =

The gelled suspensions of Examples 36, 37 and 39 were harder than the gelled suspensions of L2, L3, L4, M2, and M3 of Example 31, and showed additional consolidation due to the zeolite present in the suspension.

By applying a similar force to a thin glass rod on the cured gel, containing 11 to 14.4% by weight of additional zeolite reduces the penetration factor by about three to four times.

Claims (26)

1. A high storage stability suspension comprising an aqueous silicate solution and a filler, characterized in that the suspension contains at least 20% by weight of silicate, the filler has a mean particle size of 0.8 to 15 µm and a specific gravity of less than 2.75 kg / kg. 1, wherein the filler is selected from the group consisting of a) zeolites, b) an amorphous inorganic substance in the form of fines or fibers which is relatively inert in an alkaline, aqueous solution containing amorphous alkali metal aluminosilicate, c) graphite or carbon black in the form of or d) mixtures thereof, wherein said suspension has a high storage stability in the absence of a stabilizer. A suspension according to claim 1, characterized in that the zeolite is of the P-type. The suspension according to claim 1, wherein the amorphous inorganic material comprises a synthetic amorphous alkali metal aluminosilicate. A suspension according to any one of claims 1 to 3, wherein the mean particle size of the filler is 0.8 to 10 µm. preferably 0.8 to 5 µm. more preferably 0.8 to 8 µm and most preferably 0.8 to 2 µm. Suspension according to any one of claims 1 to 4, characterized in that the filler content is 2 to 50% by weight, preferably 10 to 40% by weight, more preferably 10 to 30% by weight. Suspension according to any one of claims 1 to 5, characterized in that the molar ratio of SiO ₂ / M ₂ O, where M is an alkali metal or ammonium ion, in aqueous solution. 9 9 « 9 9 9 9 · 9 9 9 9999 99 • 9 9 9 9 9 9 9 9 · 9 · · · · ··· The silicate is 1 to 4.5, preferably 2 to 4, and more preferably 2.6 to 4. Suspension according to any one of claims 1 to 6, characterized in that the aqueous solution. the silicate has a silicate content of at least 25% by weight. A suspension according to claim 7, characterized in that the aqueous silicate solution has a silicate content which is as high as possible. An adhesive composition comprising a suspension according to one or more of claims 1 to 8. Adhesive composition according to claim 9, characterized in that the molar ratio of SiO ₂ / M ₂ O, where M is an alkali metal or ammonium ion, in the aqueous silicate solution is 2.8 to 4.2. Adhesive composition according to either of Claims 9 or 10, characterized in that the mean particle size of the filler is less than 3 gm. 12. A drilling fluid comprising a suspension according to one or more of claims 1 to 8. 13 . Drilling fluid according to Claim 12, characterized in that the filler is graphite or carbon black in the form of fine particles. A sewage renovation liquid comprising a suspension according to one or more of claims 1 to 8. A binder comprising a suspension according to one or more of claims 1 to 8. · Ete ete · t ete ete ete ete ete tet tet tet tet tet tet tet tet tet tet tet tet tet tet tet tet tet tet tet tet tet tet · ₉ 50 * ··· · * ··· ·· ·· ·· A garbage fixation composition comprising a suspension according to one or more of claims 1 to 8. 17. Ground fixing agent comprising a suspension according to one or more of claims 1 to 8. 18. Concrete cement composition for building, characterized in that it contains a suspension according to one or more of claims 1 to 8. 19. A spray coating composition comprising a suspension according to one or more of claims 1 to 8. 2 0. A paper filler characterized in that: Comprises a suspension according to one or more of claims 1 to 11. Use of an adhesive composition according to one or more of claims 9 to 11 for the manufacture of paper products. Use of the adhesive composition according to one or more of claims 9 to 11 as binder for mineral wool or glass fibers. Use of a curing system for curing a silicate-containing suspension according to one or more of claims 1 to 8. Use of amorphous silica as a hardener for curing a silicate-containing suspension according to one or more of claims 1 to 8. Use of amorphous metal silicate as hardener for curing a suspension according to one or more of claims 1 to 8. Suspension according to claim 7, characterized in that it has a graphite or carbon black content in the form of particles of 1 to 50% by weight, preferably 5 to 35% by weight. * · ·· · · · 27 Mar: 27 Mar: The suspension of claim 1 wherein the filler comprises a zeolite type blend. P and graphite or carbon black in the form of fine particles. Suspension according to claim 27, characterized in that the particulate filler comprises a mixture of Zeocros CG180 (type P zeolite sold by Crosfield) and graphite or carbon black. A drilling fluid comprising a suspension according to one or more of claims 13, 26 to 28.