JPS6022644B2 - aqueous zeolite suspension - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a zeolite suspension for use as a raw material for cleaning agents, and more specifically to a stable zeolite suspension that maintains fluidity at ambient temperatures and does not undergo phase separation even during long-term storage. Regarding the title slurry.

The use of a water-insoluble aluminosilicate (zeolite) in place of the conventional phosphate as a builder for laundry detergents has been proposed (1977-12, 1993). As a method for producing powdery detergent containing zeolite, there is a method of dispersing finely powdered zeolite in a detergent slurry excluding zeolite and then spray-drying it. Due to the high viscosity of the detergent slurry, there are problems such as it is difficult to disperse uniformly and dust is easily generated.As a way to solve this problem, zeolite is dispersed in water and the zeolite content is 30 to 50%.
% of zeolite suspension is prepared in advance and this zeolite suspension is mixed into the detergent slurry IJ. However, zeolite-water suspensions are unstable due to the difference in specific gravity between water and zeolite, and when stored statically, the zeolite will settle and separate, which is not preferred.

Methods for stabilizing zeolite aqueous suspensions include adding a water-soluble nonionic activator (Tokusei 1989-91898) or using a combination of a water-soluble nonionic activator and a soluble salt (Tsubaki 1977-91898).
155200) or dispersion in a sodium silicate solution (Japanese Patent Application Laid-Open No. 54-164504). However, in the case of poorly water-soluble nonionic surfactants, adding a sufficient amount to stabilize the viscosity of the suspension, especially at low temperatures, has been proposed. Since the viscosity increases and the suspension loses its fluidity at room temperature, the suspension needs to be stored and pumped while being heated and kept warm, which poses problems in actual operation, equipment, and equipment. When a water-soluble nonionic surfactant and a soluble salt are used together, the nonionic surfactant is water-soluble, so it does not have much effect on the viscosity of the suspension, but the stabilizing effect is insufficient, and a considerably large amount Since a non-ionic activator is required, some of the non-ionic activator will be scattered during the hot air lamp fog drying process of the subsequent manufacturing process of powdered detergent, and special equipment is required to prevent environmental pollution. This is not a good method due to other reasons.

In addition, the method of dispersing fine zeolite in an aqueous sodium silicate solution uses sodium silicate as one of the detergent raw materials, and is a simple method in terms of operation, but when stored for a long time, a sticky gel-like substance gradually deposits in the lower layer. This gelatinous material is difficult to redisperse, and therefore requires sufficient storage whenever stored, which poses a problem in practical operation. The inventors of the present application have conducted intensive research to obtain an aqueous zeolite suspension that is stable even during long-term storage, has good fluidity even at low temperatures, and is easy to handle. We discovered that by using a specific water-soluble salt in combination with a specific water-soluble salt, the amount of non-ionic active agent scattered during hot air drying could be extremely reduced, and a stable and fluid zeolite suspension could be obtained. Based on this, the present invention was completed.

That is, the aqueous zeolite suspension of the present invention contains [a] 35 to 50% by weight of fine zeolite as anhydride, {b'0.2
~0.4% by weight of a scale-melting nonionic surfactant and {
c}0.3-3. % by weight of one or more water-soluble salts selected from the group of sodium sulfate, sodium carbonate, sodium chloride and sodium citrate.

The present invention will be explained in more detail below.

(a) As the zeolite, natural and synthetic zeolites can be used. Synthetic zeolites include A-type, X-type, Y-type, etc., but A-type zeolite is most preferred. The average particle size of zeolite is 0.5-10 French, preferably 1-10
5A is good. The amount of zeolite is 35-5.9% as anhydride, preferably 40-45M%. If it is less than 35%, the solid content of normal detergent slurry is more than 35%, so when zeolite slurry is added to the detergent slurry, the water content in the detergent slurry increases and the load during drying (Akebono fog) increases. Undesirable.

If it exceeds 50%, the viscosity of the zeolite slurry becomes high and handling becomes difficult.

As the nonionic activator, one that is water-resistant and has a cloud point of a 1% aqueous solution below room temperature is used.

Typical examples thereof include ethylene oxide and/or propylene oxide adducts of aliphatic alcohols with 9 to 2 carbon atoms, such as chasal alcohol ethoxylates (EOPs).
= 1 to 3), beef tallow alcohol ethoxylate (EO P
= 2-7), oleyl alcohol ethoxylate (EO
P=2-7), alkylphenol having 6-12 carbon atoms, ethylene oxide and/or propylene oxide adducts, such as nonylphenol ethoxylate (EO P=2-6), and the like. Here, “E
"OP" represents the average number of added moles of ethylene oxide. The amount of nonionic activator added is 0.2 to 0.4 M%.

If it is less than 0.2%, static layer stability will be poor and layer separation will occur.
．． If it exceeds 4%, the viscosity of the slurry increases due to long-term storage, and it loses fluidity, making it difficult to handle. 'c- One or more of sodium sulfate, sodium carbonate, sodium chloride, and sodium citrate is used as the water-dropping salt,
Preferred is sodium citrate.

The amount of water-soluble salt is 0.3 to 3.0%, and if it is less than 0.3%, the stability will be poor, and if it exceeds 3%, the viscosity will be high and the fluidity will be lost, making it difficult to handle.

Even if the above-mentioned nonionic activator and water-soluble salt are used alone, sufficient effects cannot be obtained. Example [b - Nonionic active agent and 'c] Aqueous zeolite suspension No. 1 was prepared with the following formulation by changing the type and amount of the water-soluble salt as shown in Table 1. 1~No. 15 was prepared.

A-type zeolite 4 skin t% (Mizusawa Chemical Silton, average flow rate 1.4) Nonionic active agent
Predetermined amount % water-soluble salt Predetermined amount % water Remaining amount These were subjected to a storage test to measure separation stability and viscosity change after storage, and the results are shown in Table 1.

The viscosity and storage stability were measured and verified as follows. [11. Viscosity Measured using a B-type viscometer at a rotational speed of 2 pm and 2500 rpm.

If the viscosity exceeds 10 ml, the fluidity becomes low and actual handling becomes difficult, which is not preferable. (2) Storage stability The suspension was placed in a glass bottle, sealed and stored statically at 25 qo.

Separation stability and viscosity were measured over time. Separation stability is determined by visually inspecting the upper transparent layer, and determining the gel-like substance deposited in the lower layer by gently inserting a diameter 5 glass rod vertically from the top of the glass bottle and measuring the length of time when it hits the gel-like substance and stops. The density is measured and expressed as volume % based on the total amount. Separation stability is good if the upper layer is 30% or less and the lower layer is 1% or less after static storage for 9 days.

Table-1 (1) * is the aqueous zeolite suspension of the present invention.

Claims (1)

[Claims] 1 (a) 35-50% by weight of fine zeolite as anhydride, (b) 0.2-0.4% by weight of poorly water-soluble nonionic surfactant, and (c) 0.3-3.0% by weight. An aqueous zeolite suspension characterized by containing one or more water-soluble salts selected from the group of sodium sulfate, sodium carbonate, sodium chloride and sodium citrate.