Classifications

• • C—CHEMISTRY; METALLURGY
  • C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
  • C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
  • C11D3/00—Other compounding ingredients of detergent compositions covered in group C11D1/00
  • C11D3/02—Inorganic compounds ; Elemental compounds
  • C11D3/12—Water-insoluble compounds
  • C11D3/124—Silicon containing, e.g. silica, silex, quartz or glass beads
  • C11D3/1246—Silicates, e.g. diatomaceous earth
  • C11D3/128—Aluminium silicates, e.g. zeolites
• • C—CHEMISTRY; METALLURGY
  • C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
  • C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
  • C11D3/00—Other compounding ingredients of detergent compositions covered in group C11D1/00
  • C11D3/02—Inorganic compounds ; Elemental compounds
  • C11D3/04—Water-soluble compounds
  • C11D3/08—Silicates

Definitions

• Sodium metasilicate is an essential component of so-called machine cleaning agents that are used in machine-based cleaning processes - for example in the known dishwashers used in the household. In an anhydrous form, this normally contains dust that attacks the airways because of its high alkalinity. Sifting the dust particles can only solve this problem temporarily, because during storage, dust particles again form due to weathering. In addition, the flushing behavior of the cleaning agent is negatively influenced by fine fractions of the metasilicate
• the mechanical cleaning agents commonly used in practice today contain sodium metasilicate in intimate admixture with other components that have a reinforcing effect, with pentasodium triphosphate (STP) still being of significant importance to this day. Both components are currently agglomerated together with soda, water glass and water in the manufacture of commercially available products to form an essentially dust-free, sufficiently heavy cleaner. A sufficient density - determined as bulk density - of the material arises as a necessity due to the size of the cleaning agent built-in metering boxes.
• the object of the invention is to overcome the difficulties presented.
• the aim is to provide strongly alkaline, granular, agglomerated cleaning agents based on intimate mixtures of sodium metasilicate mixed with reinforcing builders, whereby the partial or complete elimination of STP as a mixture component is now possible.
• the invention relates to a first embodiment of the method for producing such machine cleaning agents in agglomerate form.
• the invention relates to the new, flowable, granularly agglomerated cleaning agents, or corresponding STP-free components, which can also be used as an additive to known cleaning agents of the type concerned here, and to their use in machine cleaning, for example in the context of dishwashing agents.
• the invention relates to a production process of the type described, which is characterized in that finely divided sodium metasilicate is moistened with a flowable, finely crystalline zeolite-NaA aqueous suspension and the mixture is agglomerated with intensive mixing, whereupon, if desired, the agglomerate is dried at least to remove the surface moisture
• the zeolite NaA is introduced in the form of an aqueous suspension which is used to moisten the anhydrous or essentially anhydrous sodium metasilicate.
• the humidification of the submitted dry goods is - and thus its conditioning for the subsequent agglomeration - associated with the mixing in of at least a portion of the zeolite NaA. It has been shown that in this way the production of granular agglomerates of the structure desired here is really possible for the first time.
• the fine-crystalline zeolite material can only be introduced in this form, but additional measures can be associated with this, which in particular enable a substantial increase in the proportion of zeolite in the mixture product.
• additional measures can be associated with this, which in particular enable a substantial increase in the proportion of zeolite in the mixture product. The following applies here:
• a mixture of sodium metasilicate is already used as the dry material to be agglomerated. and flowable fine-particle zeolite NaA in the dry state and this mixture is then moistened with the aqueous suspension of the zeolite NaA to the extent required for the subsequent agglomeration.
• the following step can be used to increase the zeolite content in the mixture product:
• the granular products that occur primarily in the agglomeration may require a subsequent treatment, at least to lower the surface moisture, in order to avoid undesired clumping and thus to maintain the flowability of the product.
• One possibility for drying the grain surface is the subsequent application of dry zeolite NaA powder, for example, in such a way that in the mixing system the agglomerate formation, an additional portion of zeolite NaA is added in dry powder form and briefly mixed.
• the aqueous zeolite-NaA suspension used in the process according to the invention for moistening the dry material is preferably a corresponding filter cake from the production of the synthetic zeolite, which has about 30 to 60 percent by weight and preferably about 40 to 55 percent by weight solids content. It is known that filter cakes of this type have thixotropic properties, i.e. H. appear solid at rest, but at the same time are flowable or pumpable. The method according to the invention also makes use of this.
• Filter cakes of the type described here are usually mixed with small amounts of surfactants to stabilize the suspension. Use can be made of this for the process according to the invention, but it is preferred to exclude an overall foaming mixture which is possible due to this surfactant content. Accordingly, in the case of surfactant-stabilized filter cakes, appropriate components are used which are characterized by only slight foaming. Numerous such components are known to those skilled in the surfactant field. Instead, material that is not directly attributable to the surfactants can also be used to stabilize the filter cake.
• swellable sheet silicates come into consideration here, in particular from the group of smectite clays such as Mont morillonite, hectorite and / or saponite, water glass, polymer substances based on polycarboxylic acids - such as the commercial product "Carbopol” or polysaccharides such as the commercial product "Kelzan”.
• smectite clays such as Mont morillonite, hectorite and / or saponite
• water glass polymer substances based on polycarboxylic acids - such as the commercial product "Carbopol” or polysaccharides such as the commercial product "Kelzan”.
• These stabilizers for the zeolite filter cake are usually only used in limited quantities.
• salts for example Na 2 SO 4 can also have a stabilizing effect.
• a zeolite filter cake of the stated solids concentration in such amounts that the subsequent working up of the mixed material is possible to an agglomerate .
• the amount of moisture used in each case depends on the feed material and can be determined for the specialist in a few preliminary tests. If the amount of moisture is too low, the mix does not agglomerate in the mixing stage, or only to a limited extent, to a dusty product; if the amount of moisture is too large, the product goes immediately into a very sticky and possibly sticky mixture during subsequent mixing. even pasty condition over.
• the moisture range between these product states is - in a manner known per se - suitable for agglomeration.
• the zeolite NaA can generally be introduced into the mixture in amounts of up to about 10 percent by weight.
• the sodium metasilicate is initially introduced together with dry zeolite NaA, preferably mixed with one another in the dry state and then moistened with the zeolite filter cake.
• dry zeolite NaA is known to still contain a considerable amount of moisture, which, however, is bound inside the crystal and accordingly makes the material appear dry.
• Spray-dried material which usually has a solids content of approximately 80%, can in particular be used as the zeolite-NaA dry material.
• the process measure already mentioned can be used, after the agglomeration, to apply dry zeolite powder to the still moist agglomerate surface and to attach it there.
• the combination of this last-mentioned measure with the method described first of moistening sodium metasilicate with the zeolite filter cake creates the possibility of increasing the zeolite content in the mixed product to about 20 percent by weight. If additional zeolite contents are required in the mixed product, then the use of a dry mixture of sodium metasilicate and dry zeolite NaA is recommended, if necessary in conjunction with the subsequent powdering of the wet agglomerates using dry zeolite powder.
• the agglomeration process is carried out in mixers, which are preferably equipped with moving tools and in particular enable a high energy input. It can be carried out batchwise or continuously in suitable devices.
• suitable devices for example, the known Lödige ploughshare mixers or other comparable devices are suitable.
• a preferred water content during agglomeration is approximately in the range from 20 to 30 percent by weight, in particular approximately 22 to 26 percent by weight for the case of the preparation of mixtures of substances, the zeolite-NaA and sodium metasilicate the weight ratio of about 1 to 1.3 included.
• the numerical values for the water content relate to the total water and thus include the water content bound in the zeolite NaA.
• the agglomeration is carried out in particular in the temperature range from approximately 30 to 75 ° C. and preferably in the range from approximately 45 to 75 ° C.
• a particularly suitable temperature range for this agglomeration treatment is about 50 to about 65 ° C.
• the tendency to form lumps becomes more apparent the lower the mixing temperature is selected within this range.
• Such a tendency to form lumps may indeed be desirable - if a particularly solid-rich incorporation of dry zeolite powder is desired - on the other hand, working in the particularly preferred temperature range of about 50-65 ° C.
• the goods to be handled in a large-scale process be relieved.
• Post-drying for example in a fluidized bed and / or powdering of the primary agglomerates, favors often the bulk density of the process product.
• These measures promote the formation of the agglomerate in the form of individual grains. This pushes the bulk weight of the goods upwards.
• the formation of grape-like caking of the agglomerate grains can be determined, which generally leads to a material with a lower bulk density.
• Preferred bulk weights are in the range from approximately 750 to 1200 g / l and in particular in the range from approximately 950 to 1200 g / l.
• the mixing time required for agglomerate formation is in the range of a few minutes, usually in the range of about 1 to 4 minutes.
• the increase in the viscosity of the zeolite filter cake used for moistening the zeolite filter cake generally leads to an increase in the mixing time.
• a further measure which falls within the scope of the action according to the invention can also increase this post-mixing time.
• an additional amount of water is added to the mixed material without the simultaneous addition of suspended zeolite NaA.
• the formation of the agglomerate is very easy to determine.
• the power consumption of the mixing device increases. In this way, the course of the agglomeration process can be followed on the basis of the power consumption of the mixer motors and thus the mixing process can be terminated at the right time.
• the invention further relates to the granular, agglomerated, flowable, alkaline cleaning agents of the type described here, which contain sodium metasilicate and zeolite-NaA as essential mixture components.
• Zeolite NaA is especially detergent grade material.
• Mixtures of the type according to the invention usually contain about 30 to 85 percent by weight sodium metasilicate and 5 to 50 percent by weight zeolite NaA.
• the rest of the mixture of substances consists of moisture and optionally additives, the substances described in connection with the manufacturing process being useful additives.
• the cleaning agents according to the invention preferably contain about 40-50 percent by weight sodium metasilicate to about 30-40 percent by weight zeolite NaA.
• the liter weights are between about 750 and 1 200 g.
• the flushing properties of the agglomerates are particularly dependent on the particle size distribution.
• the material is essentially free of portions ⁇ 0.4 mm, the grain size distribution extending in particular in the range from about 0.4 to 2 mm.
• the mixed agglomerates according to the invention can be used as cleaners in machine cleaning with complete replacement of the previously used STP.
• Mixed agglomerates according to the invention are, however, also suitable in any ratio to the partial replacement of the tripolyphosphate with zeolite NaA. The following options are particularly suitable for such a partial replacement:
• STP / prehydrates with a water content of about 5 to 22% by weight are preferred, preferably those with a water content of 6 to 8% or 15 to 20% by weight.
• the mixing of the mixing agglomerates described here with other, in particular granular cleaning components, as are known and / or desired in cleaning agent mixtures of the type concerned here also falls within the scope of the invention.
• the mixing of the mixed agglomerates produced according to the invention with dust-free sodium nasilicate agglomerates produced in a separate process step is particularly suitable according to the teaching of the parallel patent application P (D 7171).

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• Chemical & Material Sciences (AREA)
• Inorganic Chemistry (AREA)
• Life Sciences & Earth Sciences (AREA)
• Engineering & Computer Science (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Oil, Petroleum & Natural Gas (AREA)
• Wood Science & Technology (AREA)
• Organic Chemistry (AREA)
• Detergent Compositions (AREA)
• Silicates, Zeolites, And Molecular Sieves (AREA)

Applications Claiming Priority (2)

Publications (3)

Family

ID=6302983

Family Applications (1)

Country Status (2)

Cited By (3)

Family Cites Families (2)

• 1986
  • 1986-06-13 DE DE19863620009 patent/DE3620009A1/de not_active Withdrawn
• 1987
  • 1987-06-05 DE DE8787108161T patent/DE3768862D1/de not_active Expired - Fee Related
  • 1987-06-05 EP EP87108161A patent/EP0249163B1/fr not_active Expired - Lifetime

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