DE504598C - Process for the mechanical dispersion of compounds which are sparingly soluble or insoluble in water - Google Patents

Description

Process for the mechanical dispersion of compounds that are sparingly soluble or insoluble in water The subject of patent 478 igo is a process for the mechanical dispersion of alkaline earth and heavy metal salts of phosphoric acids and arsenic acids, possibly in the presence of protective colloids, which essentially consists in the fact that the peptizers are alkali salts Arsenic acids or phosphoric acids can be used, which arise from the ortho acids by elimination of water or can be thought of as originating in this way, ie are lower in water in relation to these ortho acids. Of these compounds, the following are particularly suitable: the alkali metaphosphates, specifically preferably the alkali salts of the polymeric (complex) compounds, such as tri-, tetra-; Hexametaphosphates, e.g. B. Kaliumnatriummetahexaphosphat, further the Alkalipyrophospbate, such as sodium pyrophosphate, the Alkalimetaarseniate and -pyroarseniate such. B. sodium. pyroarseniate; also the alkali salts of the corresponding thioacids (sulfonic acids), i.e. the salts of those meta- and pyro-acids in which the oxygen is wholly or partially replaced by sulfur, e.g. B. sodium pyrosulfoarsenate.

It has now been found that the compounds of these groups not only on alkaline earth and heavy metal salts of phosphoric and arsenic acids in their mechanical dispersion have a peptizing effect, but also excellent peptizers for other compounds that are sparingly soluble or insoluble in water. (The Colloidization of inorganic substances with the help of peptizers is known.) So it has been shown in execution of the present process that calcium carbonate (CaCOa), barium sulfate (BaS04) and barium carbonate (BaCOg), lead carbonate (PbCO $), Calcium sulfate (CaS04), zinc sulfide (ZnS) (or lithepone) and zinc carbonate (ZnC03) when using the peptizers, which are new for this purpose, by mechanical dispersion can be converted into the colloidal state, with the possibility of to get highly concentrated products. This is all the more surprising than some det_ mentioned substances, such as B. barium sulfate, so far on an industrial scale at all could not be peptized, while other substances, such as zinc sulfide, did Could be colloidized mechanically, but only brine of low concentration delivered.

The method has a very general applicability. This is how it works it, with its help z. B. also ocher (iron oxide), bolus (water-containing alumina iron oxide silicate), Kaolin, talc (hydrous magnesium silicate) and satin white (mixture of CaS04 and Ale (OH) e), also titanium white (titanium oxides or titanium hydrates), vine black (Frankfurter Black), sulfur, graphite; Peptize red lead (Pb304). The peptization takes place in all cases easily and quickly. At most, mechanical dispersion can be used with the peptizers to be used according to the invention in the presence of Protective colloids be made. The mechanical. Editing can be done in the presence of a Dispersant (such as water) as well as in a dry state. To the Dispersion can: the usual mechanical aids, in particular Hammer mills, colloid mills or the like., Are used. But it is by no means necessary to use such particularly effective mechanical devices. Rather, it is sufficient the intimate mixture of the goods to be colloidized with the peptizer Using a simple stirrer or the like. Also the grinding of mixtures of the relevant Good with the specified peptizers in ordinary mills results in colloid-soluble ones Products.

Embodiments i. 10 g titanium white are mixed dry with 0.5 g sodium pyrophosphate, if necessary beaten through a sieve for the purpose of finer distribution and poured into water. suspended. If you add 10 g of this mixture to 1000 cm3 of water, a permanent, milky liquid is created, a real colloidal turbidity in the sense of Zsigmondy. In contrast, untreated titanium white sinks to the bottom immediately in water.

2. io g of precipitated, wet calcium carbonate are mixed with a solution triturated with 0.5 g of sodium pyrophosphate in 12 cm of water and then in 1500 cubic meters of water bloated. In this case too, the non-peptized product is devoid of any Levitation, that; On the other hand, peptized excellently suspendable.

3. 10 g of Lithopone are rubbed dry with 0.3 g of sodium pyrophosphate and sieved and placed in 50o cm3 of water. The peptized product spreads in water in full homogeneity with white color, whereas the non-colloidized Lithopone immediately sinks to the bottom in water.

¢. i o g Lithopone are finite with a solution of i g Kaliuinnatriummetahexaphosphat rubbed in and suspended in water. It will have an effect similar to example 3 noted.

5. 1 o g ocher become dry finite 0; q. g sodium pyrophosphate mixed, ground and sifted. The ocher treated in this way remains permanently in aqueous suspension, untreated goes to bathe immediately.

6. 10 g of zinc white are treated, dry or wet, with 0.3 g of sodium pyrope: hosphat or potassium sodium hexametaphosphate.

7. io g Blanc Fixe or finely ground barite, two substances, which could not yet be peptized can be replaced by dry or wet trituration with 0.2 to 1 g of sodium pyrophosphate or 0.2 to 1 g of sodium pyrosulfarsenate process to durable, milky suspensions.

B. io g vine black with 0.5 to i g sodium pyrophosphate dry grated and ground stays in the water, almost without settling, whereas ordinary things Vine black immediately goes to the ground.

G. 10 g of kaolin, rubbed dry with 0.5 g of sodium pyrophosphate, gives a perfect colloidal solution with H2O.

ok 10 g satin white dry ground with 0.2 g sodium pyrophosphate changes to the colloidal state as soon as this mixture is placed in water.

i i. io g Analin (a natural type of plaster), dry or wet, with 0.5 g of ground sodium pyrophosphate changes into the colloidal state.

12. io g sienna, natural or burnt, but especially the former Quality can be easily peptized with variable amounts of sodium pyrophosphate.

13. io g red lead, a compound already because of its high specificity Weight has been extremely difficult to peptize up to now. B. in the colloid mill for many hours with protective colloids and a range of dispersants beat, can be done with about 2 to 10 ° J "sodium pyrophosphate in a few seconds, by mere intimate dry mixing or brief wet rubbing - without any Special equipment - transfer to the colloidal state. These suspensions represent durable, beautiful, red broth, whereas the non-peptized red lead in water as is well known, sinks to the ground instantly.

1q .. 10 g of sulfur are finely triturated o, 2 g of Sülfit waste liquor and 0.3 g of sodium pyrophosphate. A very durable colloidal solution is obtained with water.

Claims (1)

PATENT CLAIM: Process for the mechanical dispersion of in water poorly soluble or insoluble compounds, with the exception of alkaline earth and heavy metal salts of phosphoric and arsenic acids, characterized in that alkali salts are used as peptizers the arsenic acids or phosphoric acids are used, derived from the ortho acids Dehydration arise or can be thought of as arisen, d. H. in the U -, relation to these ortho-acids are less watery.