DE1667065C3 - Grinding aid - Google Patents

Description

The present invention relates to the use of an additive to improve the Properties of minerals.

When processing pretreated or untreated minerals, these usually become too Grind relatively small particles, which should be done as quickly as possible. Here are often Grinding aids used to increase the grinding speed or to increase the fineness of the particles to increase the given operating speed without adversely affecting the ground product.

By breaking up the particles when grinding minerals, new energetic surfaces are created, whose surface forces remain even after the grinding process and the Material or a poor pourability result. This leads to the fact that ground minerals through the z. B. occurring during transport vibration are compressed in such a way that they are often semi-solid and themselves do not allow to be poured out, unless you have to use considerable mechanical means to break up the compact mass Uses forces.

This agglomeration or adhesion of individual particles is referred to as “solid baking” (pack set) and determined by the Festback index; this is a relative value which numerically indicates how far a particulate material is ready to flow freely after a period of storage or after transportation. The ratio of the caking index of untreated material to that of treated material is referred to as the "solid baking ratio" and is used to compare two different samples of ground Minerals.

This caking index is determined as follows: 100 g of mineral are shaken in a 250 ml Erlenmeyer flask on a vibration plate for 15 seconds and then placed horizontally in a chuck. The flask is then rotated around its axis about 100 ml per minute by 180 ° until the material adhering to the piston head collapses. The number of rotations of 180 ° that are required for the material to collapse make up the Festback-Intlcx. The greater the energy required to break open the caked material, the higher

is the solid baking index.

It has now been found that amine salts of aryl hydroxy compounds e.g. B. Phenol as excellent Grinding aids and act as hardening inhibitors for minerals without z. B. in cement Strength of the concrete is impaired.

Accordingly, the invention relates to a mixture which consists of a mineral and one with this Mineral intimately mixed amine salt of an arylhydroxy compound consists for the production of the invention New additives used are one or more arylhydroxy compounds with one or more several amines mixed The starting materials can be pure chemicals or starting materials with Be impurities. The methods of making these additives are known to be preferred equimolar parts of amine and arylhydroxy compounds used

The arylhydroxy compound preferably consists of a phenyl or naphthyl radical which is through a hydroxyl radical is substituted and which is otherwise unsubstituted or by one or more Nitro groups, halogen groups, preferably through chlorine, alkyl radicals, preferably with 1 to 5 carbon atoms and in particular methyl radicals, through aryl radicals, amino or alkoxy groups with preferably 1 to 5 Carbon atoms is substituted.

Preferably the amine is a compound of the following general formula:

Ri

in which R | a hydrogen atom or a substituted one or unsubstituted alkyl radical, such as hydroxyalkyl or aryl ζ. B. Alkaryl radical and R2 is a hydrogen atom or a substituted or unsubstituted alkyl radical e.g. B. a hydroxyalkyl radical and Rj a hydrogen atom, a hydroxyl radical or a substituted or unsubstituted alkyl radical, e.g. B. a hydroxyalkyl or aryl radical or a compound of the following formula:

ΓΊ

R ⁴ NR ⁵

> ii in which

Γ 1

R ⁴ N

a substituted or unsubstituted pyrrolidinyl, pyrrolidyl, pyrrolyl, morpholinyl, piperidinyl or piperazinyl radical and R ⁵ denotes a hydrogen atom or an alkyl or hydroxyalkyl radical; or Y- (Re) _n ,

mi in which Y is a pyridyl, pyrimidinyl or pyridizinyl radical and R6 is a halogen atom or an alkyl or hydroxyl radical and η has the value from 0 to 5.

Suitable amines are, for example, ammonia,

hi ethylamine, diethanolamine, monoethanolamine, triethylamine, Triethanolamine, aniline, p-toluidine, m-phenylenediamine, Dimethylaniline, diphenylamine, 2,4,6-tribromaniline. N-phenylhydroxylamine, / J-phenethylamine, morpho-

Hn, pyridine, piperidine, pyrrole, pirroline, pyrrolidine, Pyridazine, pyrimidine, N-methylmorpholine, 4- (2-aminoethoxy) -äthylmoφholin, Dimethylpyridine, dimethylethylpyrrole and piperazine.

Naturally occurring inorganic minerals such as phosphate rock are sometimes used as minerals processed minerals such as concentrated iron ore and mixtures of minerals such as cement, clinker or ceramic fabrics treated in this way. For example, you can use such grinding aids Treat beryllium oxide, limestone, gypsum, clay and bauxite. Such grinding aids are particularly valuable in cement and especially portland cement, in which they even increase the strength of the lead set concrete. Portland cement is one of the hydraulic cements, which is essentially made up of two calcium silicates and a smaller amount of calcium aluminate. Such cements are produced by an intimate mixture of a finely divided limestone together with clayey Material processed into a clinker and then this ground together with about 2% plaster of paris or with another calcium sulfate to achieve the desired setting properties of the finished cement. The amine salts are preferably added to the clinker, to increase the grinding efficiency and a subsequent plague baking of the finished cement avoid; however, they can also be added at a later point in time. Improving the Properties is independent of the point in time of addition, and it’s in particular an increase in Strength in hardened concrete.

The grinding aids according to the invention are used either dry or liquid. Air. Reasons of For simplicity, aqueous solutions can be used that are precisely metered into the production stream can be. Less soluble grinding aids can be mixed with an appropriate wetting agent, e.g. B. Sodium dodecylbenzenesulfonate. The grinding aid can be added to the mineral prior to grinding can be added or can be added to the grinder at the same time as the material.

If only the caking is to be reduced or a better flowability is to be achieved - e.g. B. at Conveyance or pneumatic transport - so the grinding aid can go to any other Time to be added during work-up.

The amount of the grinding aid can vary widely, but it is preferably 0.001 up to I and in particular 0.004 to 0.4% solids, based on the weight of the mineral solids, Added There is no upper limit on the amount of grinding aid added, but is usually only enough added to achieve the desired flowability and surface reach.

The grinding aids according to the invention are preferably used alone, but can also be used with one or several other grinding aids or other additives are processed together.

In the following, the invention is to be explained in more detail by means of examples.

example 1

The following table shows the effectiveness of the as Ii Mah: auxiliaries used triethanolamine phenoxide reproduced, which is made by mixing equimolar parts of triethanolamine and phenol became. The measurement results were obtained with a Portland cement type 1, which is used in the Laboratoriumstahlku-2 » gel mill was ground at 99 ° C and 3403 revolutions.

Amount of addition Surface after increase in% (solids per BIaine crhVg opposite to Solids) Blank sample 0.01 3114 4.21 0.02 3128 5.20 0.03 3121 4.45 0, (K 3134 5.41 0.06 3134 4.89 0.08 3184 7.09

Example 2

A grinding aid was prepared by mixing 34 parts by weight of a 50:50 mixture of phenol and cresol with 65.9 parts by weight of a 50:50 mixture of horpholine and triethanolamine. The grinding efficiency was determined with Portland cement type 1, which was ground in a laboratory steel ball mill at HO ⁰ C and 4941 revolutions. At a content of 0.12% by weight, based on the cement weight, there was an increase in the values for the surface according to BI ai η e of 6.75% compared to the blank sample.

The additives of the invention are also used with good results in grinding others Minerals other than cement used, such as grinding aids for phosphate rock and iron ore.

Claims (4)

Patent claims: 1. Use of an amine salt of an arylhydroxy compound as an additive to minerals, in particular Cement and cement-forming mixes. 2. The use of an additive according to claim 1 in an amount of 0.001 to 1 wt .-% and preferably 0.004 to 0.04 weight percent based on the weight of the mineral. 3. Use according to claim 1 or 2, characterized in that a triethanolamine phenoxide or a reaction product of morpholine and triethanolamine with phenol is used. 4. Mineral mixture that is a derivative of an arylhydroxy compound contains, characterized in that as a derivative of an arylhydroxy compound and as a caking inhibitor from an amine and the arylhydroxy compound by reaction on the Hydroxyl group formed salt is used.