DE10357541B4 - Process for producing an easily stirred sediment of smectite clay minerals, in particular bentonite, in aqueous media - Google Patents

Abstract

Process for producing an easily stirrable sediment of smectite clay minerals, in particular bentonite, in water, comprising the following process steps:
Grinding and / or sieving a smectite clay mineral from a natural or modified smectite, in particular bentonite, to a mineral flour,
Mixing the mineral flour with a slightly soluble in water salt or salt mixture in a ratio of smectite mineral to salt of 95: 5 to 5: 95 with humidification, so that a good mix- and kneadable dough is formed,
Mixing, kneading and shaping and granulation with gradual drying to a moisture content below 20% by weight,
- Introducing the dry granules in water or other aqueous solution liquid, dissolving the salt content therein and sedimenting the insoluble mineral portion, the latter is then easily stirrable to a dispersion.

Description

The The invention relates to a method for producing an easily stirrable Sediments of smectite clay minerals, in particular bentonite, in Water or water Media, whereby from one to a mineral flour ground and sifted smektitischen Clay mineral from a natural Occurrence or of a modified mineral.

Certain, always very fine-grained three-layer clay minerals belonging to the phyllosilicates are called smectites or smectite clay minerals. Crystallographically, these minerals are sandwiched by a central layer of octahedral coordinated cations sandwiched by two layers of [(Si, Al) O ₄ ) tetrahedra. Corresponding to the chemical substitution in the octahedral layer, various clay minerals known by their mineralogical name arise, such as montmorillonite (Al ³⁺ ), saponite (Mg ²⁺ ) or nontronite (Fe ³⁺ ). Further modifications can be generated due to the imbalance in the charge balance. Replaceable cations, such as sodium, calcium or potassium, can be incorporated between the layer interstices.

When important mineral with a high montmorillonite content is obtained as natural bentonite Clay mineral cleaned and ground. Because this mineral is virtually unlimited to disposal The invention relates primarily to the use of bentonite.

Under modified bentonites are understood to be bentonites whose properties were changed according to their purpose. Mostly aim the modifications to a rheological or adsorptive enhancement. This is how the swellability becomes of calcium bentonite is increased by exchange of the alkaline earth metal ions, it arises Sodium bentonite, also called active bentonite. The specific surface can be increased by treatment with inorganic acids. Such and other, Modifications known to the person skilled in the art are intended to be modified Bentonites are understood. The essential mineralogical remain Properties of the bentonite, which this by the high proportion at montmorillonite gets, determining.

Of the The term "crude bentonite" basically describes earth-moist Qualities, directly from the pit, without any treatment. It will ever come either natural by location Calcium or sodium bentonites which are primarily for the following Procedure should be used. A common modification is the alkaline wet activation of calcium bentonites by soda, the thereby becoming sodium bentonites. The latter have opposite the Starting materials an enlarged surface and a better swelling capacity. For the use As bleaching earths bentonites are activated sour.

On the introductory ones Notes at RÖMPP, CHEMIE LEXICON, keywords "smectite" and "bentonite", may be referred to.

The Dispersing bentonite as a water additive for cleaning and clarification of waters, but also for clarification of drinking fluids, is known from WO 00/75079. From this writing is also the Use of bentonite for the internal and external therapeutic and balneological application of bentonite suspensions and Dispersions in water are described.

at the known method is the bentonite powder with a mixture from crystalline acidifier and one releasing gas in response to the dissolved acidulant Substance mixed. Subsequently water is added, whereby by the subsequent development of gas bubbles under Reaction of the acidifier with the gas-releasing substance, a dispersion of the powdery mineral sediment takes place.

adversely in this process, on the one hand, the acid reaction mixture is relative is expensive.

It is known EP 0 765 842 A1 a method of removing heavy metal contaminants from an aqueous system, wherein the aqueous system is contacted with a mixture of one or more smectite clays and ammonium salts. The mixture of ammonium salts and smectite clays gives an organically modified smectite clay that sorbs heavy metal contaminants in dispersed form, whereby sorbed smectite clay complexes are recoverable from the aqueous system. The special ammonium salts are no longer separately soluble after binding to the smectite clays.

From the GB 2 294 456 A For example, a method of preparing a composite of Na-bentonite and Ca-bentonite components for treating contaminated water is known. The Ca bentonite component is highly acidic. The mixture is prepared in two separate aliquots and added to the water.

From document WO 02/00350 A1 a method for the separation of attapulgite from natural clay is known. To redisperse the obtained attapulgite in water, stirring methods are used Wundt.

A chemical composition for treating contaminated wastewater with oil contaminants is out US 4,415,467 known. The composition consists of bentonite with admixtures of Ca-Al silicates with alkaline Ca compounds (CaO or Ca (OH) ₂ ). In addition, coagulants, acids and acid salts are used.

It is also pointed out US 4,795,564 , Here a method for the treatment of waste water is described, in which already swellable clay minerals are present. Dissolving salts are added to these effluents, which attach themselves to the swellable clay minerals and increase their dispersibility by increasing the density and stability of the particles.

For the invention sets itself the task of being a reliable and named known dispersion of the same very difficult dispersible smectite clay minerals, in particular bentonite or its modifications, to achieve in water, being inexpensive Additional substances are to be used, the dispersion largely inert opposite the body surface of the Let people or other substances used.

• – Vermahlen und/oder Sieben eines smektitischen Tonminerals aus einem natürlichen oder modifizierten Smektit oder Bentonit zu einem Mineral-Mehl,
• – Vermischen des Mineral-Mehls mit einem in Wasser leicht löslichem Salz oder Salzgemisch in einem Verhältnis von Bentonit zu Salz von 99 : 1 bis zu 1 : 99, vorzugsweise 95 : 1 bis zu 5 : 95, unter Befeuchtung, so dass ein gut misch- und knetbarer Teig entsteht,
• – Mischen, Kneten sowie Formen und Granulieren unter allmählicher Abtrocknung bis auf einen Feuchtegehalt unter 20 Gew.-%,
• – Eintragen des trockenen Granulats in Wasser oder einer anderen wässrigen Lösungsflüssigkeit, Auflösen des Salzanteils darin und Sedimentieren-Lassen des unlöslichen Mineral-Anteils, wobei letzterer anschließend leicht zu einer Dispersion aufrührbar ist.

This object is achieved by a method with the following further method steps:

• Grinding and / or sieving a smectite clay mineral from a natural or modified smectite or bentonite to a mineral flour,
• Mixing the mineral flour with a slightly water-soluble salt or salt mixture in a ratio of bentonite to salt of 99: 1 to 1:99, preferably 95: 1 to 5: 95, with moistening, so that a good mix - and kneadable dough arises,
• Mixing, kneading and shaping and granulation with gradual drying to a moisture content below 20% by weight,
• - Introducing the dry granules in water or other aqueous solution liquid, dissolving the salt content therein and sedimenting the insoluble mineral portion, the latter is then easily stirrable to a dispersion.

One separate moistening is not necessary if, of course, moister, Raw concrete mined in open pit or other equivalent smectite undried mixed with salt, kneaded and shaped.

Basically in the aforesaid preparation, to commercially available bentonites and other smectites resorted become. Bentonite flours are also commercially available.

By the entry of the smectites, the pH is usually increased. By Using the salt will make it swell and thus insoluble temporarily prevents what makes the suspension easier. The salt concentration around the layer packages around first prevents the storage of water between the individual layers and thus the swelling of the silicate, The individual layer packages do not attract and tend with it not for agglomeration. This makes them easier to distribute in water. By the subsequent But lowering the salt concentration in water then sets a swelling process in the liquid distributed layer packages to which now the stored water can get. The salt acts in the moment of wetting in principle as a release agent between the individual layer packages, the Decreasing the concentration loses this effect.

Preferably the introduced fraction is in water or in another solution liquid at soluble Salt below the amount that leads to saturation of the solution.

• – ein anorganisches Salz, insbesondere ein Salz aus der Gruppe der Halogenide der Metalle Na, K, Mg, Ca, Al oder Fe oder aus Gemischen davon;
• – Borax (Na₂B₄O₇);
• – ein Salz aus der Gruppe der aus einem kationischen Metallrest und einem organischen Anion-Rest bestehenden, löslichen Salze.

As salts, it is possible, for example, to choose:

• - An inorganic salt, in particular a salt from the group of halides of the metals Na, K, Mg, Ca, Al or Fe or mixtures thereof;
• Borax (Na ₂ B ₄ O ₇ );
• A salt from the group consisting of a cationic metal radical and an organic anion radical, soluble salts.

The solubility of the salt should be high, with a solubility below in water at 20 ° C understood which is at least 3.5g per liter.

The mean grain size of the ground Tonminerals should be less than 30μm in experience.

When Water temperature is assumed to be a room temperature (22 ° C). The temperature of the water at entry of the granules can but between 5 ° C and 100 ° C amount.

When Intermediate step to lower the salt content in the saline liquid is decanted with the sedimented bentonite, the water supernatant and then drinking water or distilled water.

The granules produced by the process may have one or more dispersible color substances, fragrances, refatting substances, antiseptics, essential oils, pharmaceuticals, cosmetics, washing-active substances, inert inorganic and / or organic substances in granular or powder form, preferably in physiologically acceptable amount.

embodiments for the explained above Methods are described below. As far as in the following Examples of final Granulating the speech, it should be noted that this step even before and during drying, i. e. it is by means of granulation or Pillers a crumb-like Consistency produced, which is finally dried. Also can the granules pressed into specific shapes, such as cubes, cones or figures become.

example 1

Sediment base for a Bath salts

1.0 kg of purified, more natural Sodium bentonite (origin: Wyoming, USA) is dried and in one ball mill to a grain size below Grind 40μm and subsequently sieved; while the milling process becomes the ball mill 9.0 kg of cooking salt added. The dry mixture is mixed in a kneader with about 0.5 l of water turned on and kneaded at a temperature of about 40 ° C and intimately mixed, until the residual moisture content has fallen to 15% by weight of the mixture is. The resulting mixture becomes a granulate with an average particle size of 2 mm broken and bottled.

Example 2

Drilling fluid sediment for drilled holes in the soil

9.3 kg of an alkaline activated bentonite (Aktivbentonits) dried and in a ball mill to a grain size of below Grinded 25μm. In the same procedure as Example 1, the bentonite 0.7 kg of cooking salt and 1.0 l of water and the mixture at a Temperature of 40 ° C kneaded until the residual moisture content has fallen to 12.5 wt .-%. The resulting mixture becomes a granulate with a mean grain size of 4 mm broken and bottled.

Example 3

Bath for psoriasis people

The Starting materials 5.0 kg dead sea salt, 3.0 kg calcium bentonite and 2.0 kg bolus alba (whiter Kaolin clay) are dried and ground according to the process steps Example 1.

Example 4

Hauterfrischendes bath

The Starting materials 4.0 kg boiling salt, 3.0 kg sodium bentonite, dried and grind, 2.0 kg bolus alba, dried and ground, 0.5 kg shale, light, dried and ground and 0.5 kg dried Melissa are ground, dressed and granulated accordingly Example 1.

Example 5

Bath for Thalasso therapy

Of the Starting material 8.0 kg of humid raw bentonite (locality island of Milos, Greece) becomes yellowish with dry unclean sea salt Color (won in the salt gardens the island Milos, Greece) with small amount of water or without further Addition of water mixed, ground and granulated, according to Example 1.

Example 6

Bath salts for Thalasso therapy

9.0 kg Calcium bentonite, earth-moist, is mixed with 1.0 kg ground sea salt intimately mixed, dried and ground to a granulate.

Example 7

Bath salts for a calcium balneo therapy

8.0 kg of Bavarian calcium bentonite, dried and ground to one Grain size of less than 30μm, will with 2.0 kg of saturated Sole of rock salt mixed without further addition of liquid, kneaded and dried to a residual moisture of 15 wt .-% and then broken and granulated to a particle size of 1.5 mm on average.

Example 8

Bath salts for the treatment of skin diseases

The Starting materials 5.0 kg calcium bentonite, dried and ground, 1.0 kg bolus alba, dried and ground, 1.0 kg shale bright, dried and ground, as well as 3.0 kg saline salt kneaded with mixing water, wherein according to Example 1, a drying takes place, so that the mixture then either directly as a packing pad can be used or is to be converted into a granulate.

Example 10

Mixture for cleaning slightly contaminated wastewater

The Starting materials 8.5 kg sodium bentonite, dried and ground, and 1.5 kg regeneration salt are mixed with Wasserzumischung, kneaded, dried and ground to granules.

Example 11

Bath salt for soda baths for the foot treatment

Here 8.0 kg of sodium bentonite are dried and ground, 0.1% sodium carbonate (Soda) and 1.0 kg of sodium chloride (common salt) mixed, kneaded and granulated.

Example 12

Bath salt for soda foot bath

The Starting materials 7.5 kg sodium bentonite, dried and ground, 1.5 sodium bicarbonate (soda) and 1.0 kg of evaporated salt mixed, dressed, kneaded and granulated, as is the example 1 is known.

Example 13

Dyed bath salt

The Starting materials 7.5 kg sodium bentonite, dried and ground, 1.0 kg of titanium dioxide, finely ground and 1.5 kg of sodium chloride (common salt) are dressed, kneaded and diced to 2.0 × 2.0 × 2.0 cm pressed and dried to a residual moisture of 0.5 wt .-%.

Example 14

Sodium bentonite bath salts

Out the starting materials 5.0 kg of Greek sodium bentonite, dried and ground, 3.0 natural zeolite (clinoptilolite), very finely ground, 1.0 kg of saline salt and 1.0 kg of lemon essential oil a fragrant bath salt mixture prepared, which is granulated as in Example 1.

Example 15

Bath salts for a calcium balneo therapy

Out the starting materials 6.5 kg of Bavarian calcium bentonite, dried and grind, 2.0 kg of sodium citrate, 1.0 kg of avocado oil, 0.3 kg Fluid lecithin as emulsifier and 0.2 kg lavender oil becomes a greased mixture produced. The avocado oil replaces the water in this case. The mixture is kneaded thoroughly and pressed into tongues that are wrapped in plastic films.

Example 16

The Starting materials of Example 14 are varied so that instead of lemon oil finely ground mint leaves be used.

Example 17

Out the starting materials 6.5 kg sodium bentonite, dried and ground, 2.5 kg Dead Sea salt, 0.5 kg of finely ground amber flour, 0.4 kg of apricot kernel flour and 0.1 kg of orange essential oil are added with water a mixture turned on, which is kneadable and after drying and reducing the water content is ground and granulated.

Example 18

Bath salts for a green tea bath

Out the starting materials 7.5 kg sodium bentonite from Wyoming, USA, 2.5 kg of sea salt, 0.3 mineral pigments (green) and 0.2 kg of tea tree oil suitable for wellness purposes Bath salt according to example 1 produced.

To The above examples should be noted that only so much water is added until a kneadable dough is formed, which then according to Granules is processed further. By setting a higher Water content, the final product but also in the form of pastes or suspensions become. In principle, you can Therefore, almost all the above recipes are also converted into a paste form. It should also be noted that the specified salt content is also partial in an aqueous Water-salt solution can be located, e.g. in the form of seawater.

Example 19

Handwaschpaste

• 10 kg sodium bentonite
• 2 kg natural zeolite (about> 63μ)
• 2 kg saline salt
• 25 kg of water

Example 20

bath lotion

• 10 kg sodium bentonite
• 3 kg saline salt
• 30 kg of water

Under the invention also fall liquid Dispersions prepared from an aqueous carrier liquid, preferably drinking water, with readily dispersible smectite clay minerals, the according to one of the claims 11 or 12 are made.

For this be the following examples are mentioned:

Example 21

Suspension for wastewater treatment

• 10 kg Wyomingbentonite (sodium bentonite)
• 1 kg natural zeolite (about> 63μ)
• 1 kg sodium chloride (common salt)
• 25 kg of water

Certain Granules are also suitable for cleaning laundry in the washing machine. This use leaves Follow the example below:

Detergent on mineral Base, soap-free and without phosphates

• 10 kg sodium bentonite

Detergent on mineral Base, soap-free and without phosphates

• 10 kg sodium bentonite
• 4 kg natural zeolite (about <63μ)
• 2 kg sodium chloride (common salt)
• 0.5 kg sodium carbonate (soda).

Claims (11)

Process for producing an easily stirrable Sediments of smectite clay minerals, especially bentonite, in water, with the following process steps: - grinding and / or sieving a smectite clay mineral from a natural one or modified smectite, in particular bentonite, to a mineral flour, - mixing of the mineral flour with a slightly soluble in water salt or salt mixture in a relationship from smectite mineral to salt from 95: 5 up to 5:95 with moistening, so that a good mixable and kneadable dough, - Mix, Kneading and shaping and granulation with gradual drying up on a moisture content below 20% by weight, - Enter the dry granules in water or another aqueous Solvent liquid Dissolve of the salt portion in it and sediment-leaving the insoluble one Mineral portion, the latter then easily to a dispersion reagitate is. Method according to claim 1, characterized in that that the incorporated fraction in water or in another solution liquid soluble Salt is below the amount that leads to saturation of the solution. Method according to claim 1 or 2, characterized that an inorganic salt is chosen as the salt. Method according to claim 3, characterized that the salt from the group of halides of the metals Na, K, Mg, Ca, Al or Fe, or mixtures thereof. Process according to claim 3, characterized in that the salt is borax (Na ₂ B ₄ O ₇ ). Method according to claim 1 or 2, characterized that salt from the group consisting of a cationic metal residue and an organic anion residue, soluble salts is selected. Method according to one of the preceding claims, characterized characterized in that the solubility of the salt used in water at 20 ° C at least 3.5g per liter is. Method according to one of the preceding claims, characterized characterized in that the mean grain size of the ground smectitic Clay minerals or bentonites less than 30μm. Method according to one of the preceding claims, characterized characterized in that the temperature of the water at entry of Granules between 5 ° C and 100 ° C is. Method according to one of the preceding claims, characterized characterized in that to reduce the salt content in the saline liquid with the sedimented mineral or bentonite the water supernatant decan and then Drinking water or distilled water is refilled. Method according to claim 1, characterized in that the dry granules one or more dispersible dyes, fragrances, lipid replacers, antiseptics, essential oils, pharmaceuticals, Cosmetics, washing-active substances, inert inorganic and / or organic substances in granular or powder form in physiological compatible Amount to be mixed.