CS201274B1 - Sequestring ingredients for detergents - Google Patents

Description

The invention relates to the use of acid-activated bentonites as sequestering agents for detergents, which can replace 75% of the polyphosphates used so far, in particular sodium tripolyphosphate, with a slight decrease in overall sequestering efficiency.

Up to now, polyphosphates have been used as sequestering agents for detergents, namely sodium tripolyphosphate, which is a necessary ingredient for hard water washing. It is a complex binding of alkaline earth metals calcium and magnesium, which cause water hardness and binding of other metals such as iron, honey etc. A major disadvantage of polyphosphates is their interaction with wastewater, where phosphates induce eutrophication processes, ie. extraordinary growth of phytoplankton, especially algae. These processes, in particular in stagnant waters, lakes, reservoirs, estuaries, in the sea, induce water suffocation, the transition to anareobic processes associated with the release of carbon disulphide and the disappearance of biological processes in living organisms. For this reason, polyphosphate substitutes are being sought to prevent the payment of eutrophication processes in waste water. Dot-ag M is an organic compound which is capable of complexly binding alkaline earth metals. These are, in particular, the following compounds in the form of alkaline, sodium salts: complexes such as nitrilotriacetic acid, ethylenediaminetetraacetic acid. Polymeric acids, e.g. polyacrylic acid, polyethylene maleic acid, oxidized starches, lower di-atricarboxylic acids such as citric acid, tartaric acid, etc.

Some of the above types of compounds may, but only partially, below 50% replace tripolyphosphate, with the additional difficulties of polymeric compounds in the form of poor biodegradability in wastewater, and in the case of nitrootriacetic acid also suspected of a carcinogenic effect.

All of the foregoing are alkali salts, mostly sodium, which are water soluble.

More recently, ion exchangers of the type A synthetic zeolites prepared by the reaction of water glass and alumina have been proposed as calcium and magnesium binding sequestrants in washing baths. Ion exchangers of this type are insoluble in washing baths. They are prepared synthetically and are relatively expensive. In addition, the phosphates used can be replaced by roughly 50%.

For the sake of completeness, silicic acid salts, water glass, as additives for bleach stabilization, sodium perborate and protective colloids are very often used in detergent compositions. However, these are very poor in the absence of polyphosphates.

These deficiencies are overcome by the proposed additive containing 5 to 50% by weight of the total bleaching clay detergent composition having a grain size of less than 40 μνα, prepared by acid activation of bentonite, which is largely sourced from bentonites found in various locations and in CSSR.

Acid activated montmorillonite, also known under ref. bleaching clay has all replaceable cations replaced by hydrogen cations, and the washing bath undergoes a rapid exchange reaction to calcium and magnesium ions.

In addition to this pronounced sequestering effect, less polar organic and inorganic impurities are absorbed onto the bentonite particles due to the larger surface area of the acid-treated bentonite. The acid-treated bentonite is characterized by a higher negative surface charge, which has a positive effect on stabilizing the impurities in the washing bath, thus reducing the redeposition of the spin.

An important advantage of using acid-activated bentonites is that they do not cause any discomfort in the wastewater. Since these are inorganic substances, the question of biodegradability is losing its importance. On the contrary, they can take part in a process similar to the self-cleaning of water in rivers by means of clay released from the banks. They also make it possible to accelerate the coagulation process and the settling of sludge in wastewater treatment plants.

In the following, the essence of the invention is illustrated by way of example, without being limited thereto.

Example 1

Commercially bleached clay was used as sequestering agent, replacing some of the sodium tripolyphosphate. Washing was carried out on a cotton companion fabric according to CSN 80 0101 for 10 minutes at 80 ° C with a dirty model spin of the following composition:

Sunar 40 g, gelatin 3 g, black ink 22 g, refined sunflower oil 60 g, carbon tetrachloride 25 g, distilled water 200 g. It was washed on a Koltest laboratory washing machine. The whiteness of the soiled sample as well as the washed sample and the unclean sample was determined on a Zeis Jena leukometer with a white filter. The content of the ingredients of the washing bath (total of 5 g of detergents per liter of bath), as well as the washing percentage, are given in Tab. First

Tab. First

Percent wash of model cotton spin spin using 5 g of detergent per liter of wash liquor, the detergent containing bleaching clay.

component Detergent composition percentage ABS tripolyphosphate bleaching earth Na ₂ CO ₃ Na ₂ SO ₄ carboxymethylcellulose 25 40 19 15 1 25 30 '10 19 15 1 25 20 ²⁰ 19 15 25 10 30 19 15 1 25 40 19 15 1 Water hardness washing percentage 15 ° N 60.58 59,48 59.61 58.57 49.02

OBJECT OF THE INVENTION

Claims (1)

OBJECT OF THE INVENTION Use of a bleaching clay of the prepared detergent compositions, in an amount of 5 to 50% per mole by activating bentonite with a grain size of less the total weight of the detergent composition. as 40 μνα, as sequestering additive to de-