Process for stabilizing aqueous zeolite suspensions using a line

Details Process for stabilizing aqueous zeolite suspensions using a line Process for stabilizing aqueous zeolite suspensions using a line

1994-08-10

1996-03-26

Lieberman, Paul

Compositions

Water-softening or purifying or scale-inhibiting agents

252173, 25217421, 252DIG1, 252DIG14, C11D 312, C11D 172

Patent

active

055018173

DESCRIPTION:

BRIEF SUMMARY
FIELD OF THE INVENTION

This invention relates to a process for stabilizing aqueous zeolite suspensions by addition of selected fatty alcohol polyethylene glycol ethers.


PRIOR ART

Zeolites, more particularly those of the zeolite A type, have particular significance as builders in modern detergents and have largely displaced the polyphosphates used for decades. Their advantages lie not only in a high calcium binding capacity, but also and above all in their high ecotoxicological compatibility Tens. Surf. Det., 24, 322 (1987)!.
In their production, zeolites are obtained in the form of aqueous suspensions which may either be stored and marketed as such or subjected to spray drying. Zeolites show extremely low solubility in water so that zeolite suspensions readily sediment. In the most favorable case, this leads to phase separation although, normally, considerable quantities of the solid sink to the bottom of the vessels in storage, solidify and have to be removed, size-reduced and resuspended with considerable effort. In other cases, the suspension undergoes such a drastic increase in viscosity that transfer to other vessels or circulation by pumping becomes difficult, if not impossible, and always involves considerable product losses.
There has been no shortage of attempts in the past to stabilize aqueous zeolite suspensions in such a way that they remain stable in storage for a sufficient time and can be transported through pipelines without blocking them.
For example, it is proposed in German patent application DE 33 30 220 A1 to add 0.5 to 5% by weight of a mixture of fatty alcohol ethoxylates and fatty alcohol sulfates or fatty alcohol ether sulfates to the suspensions.
German patent application DE 34 08 040 A1 describes a process for stabilizing 65% by weight zeolite A suspensions with 0.01 to 0.25% by weight of xanthan gum and carboxyl- or hydroxyl-containing polymers.
According to the teaching of German patent application DE 34 23 351 A1, zeolite suspensions can also be stabilized by addition of polyglycol ethers, fatty alcohol ether sulfates, fatty acid alkanolamides or fatty acid monoglycerides at pH 9 to 10.
In addition, the use of many other stabilizers, for example polycarboxylates having molecular weights above 1,500, phosphonic acids, phosphoric acid esters, alkyl benzenesulfonates, layer silicates DE-OS 25 27 388!, alkylphenol polyglycol ethers DE 34 01 861 A1!, isotridecyl polyglycol ethers DE 34 44 311 A1! and adducts of ethylene oxide with oxoalcohols DE 37 19 042 A1!, is known from the literature.
Unfortunately, known processes have disadvantages in regard to adequate stabilization over a relatively wide temperature range, in regard to the necessary quantities of stabilizer and also in regard to the viscosity and residue-free pouring behavior of the suspensions.
Accordingly, the problem addressed by the present invention was to provide an improved process for stabilizing aqueous zeolite suspensions which would be free from the described disadvantages.


DESCRIPTION OF THE INVENTION

The present invention relates to a process for stabilizing aqueous zeolite suspensions by addition of surfactants, characterized in that fatty alcohol polyethylene glycol ethers corresponding to formula (I): atoms and
It has surprisingly been found that the use of the selected fatty alcohol polyethylene glycol ethers mentioned or mixtures thereof with one another can reliably stabilize suspensions of zeolites over a broad temperature range, more particularly from 10.degree. to 60.degree. C. The suspensions also show high stability in storage over prolonged periods, can be pumped through pipelines and can be readily poured out with only minimal product losses.
In the context of the invention, zeolites are optionally water-containing alkali metal or alkaline earth metal alumosilicates corresponding to general formula (V): x is a number of 1.8 to 12 and y is a number of 0 to 8 Chem. i. u. Zt., 20, 117 (1986)!.
Typical examples of zeolites of which aqueous dispersions may be stabilized by the process according

REFERENCES:
patent: 4072622 (1978-02-01), Ku/ hling et al.
patent: 4083793 (1978-04-01), Jakobi et al.
patent: 4169075 (1979-09-01), Kuhling et al.
patent: 4179393 (1979-12-01), Andree et al.
patent: 4264480 (1981-04-01), Andree et al.
patent: 4280920 (1981-07-01), Garvey et al.
patent: 4405483 (1983-09-01), Kuzel et al.
patent: 4483012 (1984-03-01), Ku/ hling et al.
patent: 4529541 (1985-07-01), Wilms et al.
patent: 4668420 (1987-05-01), Diehl et al.
patent: 4671887 (1987-06-01), Diehl et al.
patent: 5174918 (1992-12-01), Diehl et al.
patent: 5252244 (1993-10-01), Beaujean et al.
patent: 5298185 (1994-03-01), Leonhardt et al.
patent: 5312793 (1994-05-01), Colombo et al.
patent: 5354493 (1994-10-01), Wilms
Chem.i.u.Zt., 20, 117 (1986).
Tens. Surf. Det., 24, 322 (1987).

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