DE2134215C3 - Process for the production of detergents and cleaning agents - Google Patents

Description

The invention relates to the production of detergents and cleaning agents and in particular to the production of such agents in finely divided or powdery form by spraying an aqueous Slurry of detergent ingredients in a stream of drying gas.

Detergent powders are usually made by a process in which an aqueous slurry is poured into a Chamber is sprayed through which a gas stream is passed so that the water in the slurry is evaporated. The aqueous slurry can be at a relatively high temperature to that of the gas in which case flash evaporation of the water in the slurry during the process stalt, which is sometimes referred to as spray cooling. Often is; but the pulp on one relatively low temperature and the gas stream is heated to a higher temperature, which Process is generally referred to as spray drying. Expediently, the expression Spray drying as used herein to encompass all powder forming processes in which aqueous Porridges are sprayed into streams of drying gas.

Conventional spray drying processes are not readily applicable to the manufacture of detergent powders with high organic content because of the fire ·· or Risk of explosion "if the powder is overheated in the presence of oxygen, which is usually available" bar ", since the drying gas is normally air, In addition, there is a tendency to use the content of phosphates, especially condensed phosphates, as a structure * substances in detergents and cleaning agents B. Sodium ffipolyphosphate, decrease in the compilations because of the assumption that such a use of phosphates contributing to eutrophication, generally led to the organic content of Increase detergent powder.

The possible organic substitutes for condensed phosphates as constituents in detergents, which have heretofore been proposed include so-called polyelectrolyte builders, such as e.g. B. Sodium polyacrylate, sodium polymaleate and their

iu copolymers such as B. Sodium copolyethylene maleate, certain oxidized polysaccharides and non-polymeric builders, e.g. B. Sodium Oxydiacetate, Sodium carboxymethyloxysuccinate and sodium nitilotriaceiate. Other preferred organic constituents

Ij substances are the water-soluble salts of dicarboxylic acids the formula

R - CH (COOH) (CH ₂ ) _n - COOH

where η is 0 or 1 and R is a primary or

? (i secondary straight-chain alkyl or alkenyl group with of 10 to 20 carbon atoms is like them for example, are described in co-pending British Patent Application No. 37,961/68. The preferred Dicarboxylates are sodium alkyl succinates, which

2i can be prepared by hydrolysis and neutralization of alkenyl succinic acid anhydrides, which in turn are obtained by reaction between maleic acid anhydrides and olefins.

The amount of builders in the detergent

; ii can be up to 50% by weight, in which case the The total organic content of the detergent powder can sometimes be up to 80% by weight, if the organic content of the active detergent compounds and possible additives e.g. B. Hydrotropes, Foam Compounds

> · Stronger, anti-redeposition agents and fluorescent Agents are considered. Under these circumstances, if the powders are more than about 50% If the powders contain organic material, there is a significant risk of fire or explosion

■ so during their production in conventional spray drying processes become overdried and overheated.

According to the invention, a detergent powder with a content of synthetic active detergent

4ϊ bond and an organic builder thereby prepared an aqueous slurry of the detergent ingredient at a level not exceeding about 40% % By weight of the slurry of water in a pressure-tight vessel at a temperature of about 125 to 180 "C

ίο prepared and then the pulp is spray-dried in a gas stream at a temperature of about 100 to 250 ^{0 C.}

Using this process, it is possible to produce detergent powder under conditions that

«Before they are not so sharp in the spray drying stage, that they pose an appreciable risk of fire or explosion entail. In addition, the invention can provide valuable economic advantages in detergent powder production offer, both in terms of for that

In drying the pulp to a powder, the heat required and also the increased output as made possible in the spray drying system due to the lower water content of the pulp are reduced. Another advantage lies in the tendency of the process to deliver powder with a higher bulk density than conventional spray jib processes.

In conventional detergent powder manufacture, it is common to have BreN water contents of around 38 to 50

To have wt .-%. In the process of the present invention, the aqueous slurry should be practical Contain minimum water content, which is not more than about 40 wt .-%, preferably less than 30 % By weight of the slurry. The water content can be ί under optimal circumstances, as will be explained below, even be only about 20% by weight.

The conditions used in the spray drying are preferably as mild as possible and reasonable in order to obtain satisfactory powder production performance while minimizing any fire risk, especially for powders with higher levels of organic matter. The gas temperature in the spray drying stage is preferably from about 150 "to about 200 ^° C. The spray drying process is preferably carried out under conditions in order to obtain a free-flowing powder in a single treatment, but if desired, for example, to increase the throughput of a spray-drying tower , the conditions of the spray drying can be modified so that the initially produced powder is still moist, and the excess water is removed in a subsequent drying treatment, for example using a fluid bed, in which additional drying gas is passed through either in a batchwise or continuous process , or by using a pneumatic dryer in which the powder is dried while being conveyed through a hot gas.

Notably, it is essential to prepare the pulp under pressure in a closed vessel because of the elevated temperatures used. The pressure also serves un the broth after its preparation to carry the spray dryer ι and "the porridge for spraying into the gas inside to sputtering. The generation of the pressure in the vessel is preferably accomplished by direct steam or, since this tends to increase the water content of the pulp, by air pressure or a combination of both. The pressure in the vessel should be such as to give a pressure of about 2.8 to 45 kg / cm ² at the spray nozzle, but it can be higher e.g. B. up to about 7.0 kg / cm ² , beyond which no noticeable advantage can be achieved and the price of the system increases excessively. In practice, pressures of up to about 10.5 to 14.1 kg / cm ² are generally used in the vessel.

The inventive method is only applicable to the production of detergent powders whose ίο Ingredients are available in a suitable dry form, allowing the manufacture of aqueous pulps with contents of no more than about 40 wt .-% water. With regard to the components, which are present in the powder in the form of organic acid salts, as is customary is the case for organic builders and anionic active detergent compounds, the organic acid or its anhydride, preferably with an alkaline material e.g. B. sodium hydroxide in neutralized to the three; otherwise, if the salt is preformed, it will generally include too much water one to enable the slurry with the required amount of Less than 40% water can be produced. This is because neutralization of the acids inside the pulp general excess water required to regulate the heat and the product To make it pumpable, and drying the solution of the neutralized product to a powder is not economically. However, if a de-icing salt or an anionic active detergent compound is sufficient Dry form is available, 2nd tablespoon !, as powder or Flakes, it can advantageously be used directly in the production of pulp.

In the preferred embodiment of the method the main constituents, apart from the organic builder are in acid or anhydride form, mixed and heated to a temperature of about 100 ⁰ C to 140 ° C. The precursor of the construction material is then added, whereupon it in the pulp is neutralized and, if necessary, hydrolyzed, and the heat of neutralization causes the temperature and pressure to rise to the desired levels for spray drying. This process can be carried out batchwise or continuously.

The inventive method is of particular interest for the production of detergent powders, which include alkyl and alkenyl succinates as builders. These materials can easily prepared in anhydrous form and added in this form to the aqueous slurry, wherein Hydrolysis and neutralization takes place with the formation of the desired water-soluble salts. Some analog connections z. B. the alkylthio and alkyloxysuccinates can be used in the same way.

Other builders useful in the method of the invention include, for example the salts of α-sulfonated fatty acids, such as α-sulfonated hydrogenated tallow fatty acids, higher alkane disulfonate and sulfonate sulfonates, and soaps, all of which are Builders in detergents act with the formation of insoluble calcium salts; water-soluble salts of organic Acids including oxydiacetic acid, oxydisuccinic acid, Carboxymethyloxyber-succinic acid, hydrofuran-tetracarboxylic acid and homologues and analogs of these substances, oxidized polysecdiarides in which the Anhydroglucose rings are opened to form dicarboxyl groups, as in the floating one British Patent Application Nos. 41 512/69 and 40 100/70, and polyelectrolyte builders z. B. Sodium polyacrylate and sodium polymaleate and their copolymers z. B. sodium copolyethylene maleate; however, it should be noted that with some Polyelectrolytes may have a tendency to decarboxylate at higher temperatures. Many other Organic building blocks are available and described in the literature, for example in »Surface Active Agents and Detergents «by Schwanz, Perry & Berch.

In addition to the organic builders mentioned, the detergents usually contain one or more active detergent compounds together with the usual optional additives. the synthetic active detergent compounds are preferably anionic active detergent compounds, which are readily available and relatively inexpensive, and mixtures thereof, These compounds are Usually water-soluble alkali salts of organic sulfates and sulfonates with alkyl radicals with from about 8 up to about 22 carbon atoms, with the designation Alkyl is used to denote the alkyl moiety of higher acyl radicals. Examples of such synthetic aniortic active detergent compounds are Sodium and KaIiUnVaIkVl (Gj = Ca) benzene sulfonate,

in particular linear secondary sodium (Cio-C, ₅ ) benzenesulfonate; Sodium and potassium salts of fatty acid amides of methyl taurine; AI-kan-sulfonates z. B. those which were derived by reacting alpha-olefins (Ca -C20) with sodium bisulfide and those which were derived by reacting paraffins with SO ₂ and Cl 2 and then hydrolyzing with a base to form an arbitrary sulfonate; and OleFinsulfonate, which term is used to cover the material which is produced by reacting olefins, especially alpha-olefins, with SO3 and then neutralizing and hydrolyzing the reaction product.

It should be noted that some anionic detergent active compounds z. B. alkyl and alkyl ether sulfates, tend to hydrolyze at higher temperatures, which is the case with the present process can be exploited.

If desired, nonionic active detergent compounds can also be used. Examples include the reaction products of alkylene oxides, usually ethylene oxide with alkyl (Q - Cu) phenoien, generally having from 5 to 25 ethylene oxide units per molecule; the condensation products of aliphatic (C ₈ -C ₈ ) alcohols with ethylene oxide, generally with 6 to 30 ethylene oxide units, and products produced by the condensation of ethylene oxide with the reaction products of propylene oxide and ethylene diamine. Other nonionic active detergent compounds include long chain tertiary amine oxides, long chain tertiary phosphine oxides and dialkyl sulfoxides.

Mixtures of active detergent compounds e.g. B. Mixtures of anionic or mixtures of anionic and nonionic compounds can be used in the agents according to the invention, in particular to inform them of a regulated low foaming power. This is especially beneficial for Means to be used for use in automatic washing machines in which foaming is undesirable.

Amounts of amphoteric or zwitterionic active detergent compounds e.g. B. betaines, sulfobetaines and hydroxy-alkyl-methyl-taurine can also be used in the agents according to the invention, but this is usually because of their high levels Price not desired. When amphoteric or zwitterionic active detergent compounds are used it should generally be in small amounts Be agents based on the much more commonly used anionic or nonionic active detergent compounds contain.

Many other suitable active detergent compounds are commercially available and extensively described in the literature e.g. B. in »Surface Active Agents and Detergents ”by Schwartz, Perry and Berch.

The amount of the synthetic active detergent compound or compounds used is in generally in the range of about 10 to 50 preferably t about 15 to 30 wt. *% of the funds depending on the desired properties.

Possible additives to the detergents according to the invention include foam boosters e.g. B. coconut oil ethanolamide, hydrotropes z. B. Nairium * toluene sulfonate, inorganic salts e.g. B. alkali silicates, sodium carbonate, sodium chloride and sodium sulfate, Anti-Wiedefäblägefüngsägentieri z. B. sodium carboxymethyl cellulose, Textile softeners, fluorescent agents, dyes, germicides, fungicides, Perfumes, enzymes and chemical bleaching agents e.g. B. sodium perborate and peracid precursors. Some of the additives, particularly deoxygenating bleaching agents such as sodium perborate, will usually the detergent powders after their manufacture added by spray drying.

The invention is further illustrated by the following examples, in which parts and percentages are by weight are.

example 1

A detergent slurry was prepared by mixing the following ingredients together with stirring in one Reaction vessel at a temperature of 150 ° C and under a pressure of 40 to SOpsig and 2.8 to 3.5 kg / cnR

Components percent sentences Hexadecenyl succinic anhydride 33.7 Sodium hydroxide (50% aqueous solution) 13.7 / • -! Potassium silicate (50% aqueous solution) 11.8 Sodium dodecyl benzoI sulfonate flakes (80% active content) 25.8 Sodium sulfate 43 Sodium toluene sulfonate 1.0 Coconut oil ethanolamide 3.2 Sodium carboxymethyl cellulose fluorescent substance 0.6

The water content of the ingredients in the slurry was about 16% and with the water of neutralization and the The water vapor used to heat the porridge increased the total water content to 2 weeks. The pulp was sprayed through a 4.75 mm spray nozzle into a tower in which ascending air at a Temperature of 150 ° C and a flow rate of 45.4 kg / min was passed through to produce a detergent powder which was brittle and free flowing and contained 6% moisture and 74% organic matter.

Example 2

The procedure of Example 1 was repeated with the modification that the approach of the aqueous slurry of the following was:

Components Piocent sentences Hexadecenyl succinic anhydride 273 Dodecyl benzene sulfonic acid 19.4 Alkali silicate 13.3 Sodium sulfate 53 Sodium tulol sulfonate 0.9 Sodium carboxymethyl cellulose 0.45 Coconut oil ethanolamide 2.8 water 193 flooding agent 035 Sodium hydroxide (flakes) 10.7

The pulp would be at a temperature of 150 ° C through a 3.2 mm spray nozzle into a stream of air at a temperature of 200 ° C and a flow rate sprayed at 45.4 kg / min to yield a powder of 9% moisture and 72% organic matter

produce which in turn are brittle and frciflic and constituents was.

B c i s ρ i e I 3

An aqueous tirci was prepared by mixing the following ingredients in a pressure-tight vessel, in which the temperature was raised to 160 ° C.

Components percent sentences a-sulfonated hardened tallow acid 28.5 water 13.0 Sodium hydroxide (flakes) 6.5 Sodium dodecyl benzene sulfonate (50% paste) 19.5 fNairium-siiicai (50% aqueous solution) 19.0 Sodium carboxymethyl cellulose 0.5 Sodium ethylene diamine tetraacetate 0.3 fluorescent agent 0.2 Sodium sulfate 12.8

21)

The slurry with a water content of about 32% was ^{sprayed at 3.9 kg / cm 2} pressure through a 3.2 mm spray nozzle into an air countercurrent at a temperature of 200 ° C to obtain a free-flowing powder which was about 59 % organic matter and 5% water.

Example 4

A Detergensbrei was prepared at 150 ⁰ C and under 4.2 kg / cm ² pressure by mixing sodium dodecyl benzene sulphonate and disodium octadecane-l-sulfonate-2-sulfinate with small additions to a water content of about 28 % to result. The pulp was spray-dried through a 3.2 mm spray nozzle in a pressure of 200 ° C. with the formation of a poorly flowing powder of the following composition:

Pro / desalt

17.8

44.5 7

0.5 0.9

13.8 15.5

Sodium clodccyl bcnzul sulfonate
Natritim-alkane (Ci ₈ ) -1-sulfonal-2-sulfinate
Alkali silicate

Sodium carboxymethyl chloride
fluorescent agent
inorganic salts
(mainly sodium sulfate)
water

Example 5

A detergent slurry was prepared at a temperature of 150 ° C under a pressure of 5.3 kg / cm ² by mixing various detergent ingredients including sodium dodecyl-benzene-sul-ifonate and sodium coconut oil soap with a water content of 31.5%. The slurry was spray-dried in air at 210 ^° C. and resulted in a free-flowing powder of the following composition:

Components

2> percentages

Sodium dodecyl benzene sulfonate

Soda cd; oil soap

Alkali silicate

Sodium sulfate

Sodium carboxymethyl cellulose

fluorescent agent

Water 20

55

10 8.5 0.5 1.0 5.0

In a comparative experiment a Detcrgensi was "> produced powder by the same approach by spray drying, in which the slurry was zubereilet having a water content of about 40% and at a temperature of 90 ⁰ C. The slurry was, to a spray-drying tower under a pressure of 28 1 kg / cm ² pumped ■ »o and sprayed in air at 300 ⁰ C to a free flowing powder but yield of low bulk density in dicscrr; Fa. !! the cr'Ofuerüehe amount of heat VRAR to the water to evaporate, and thus a Powder form to about 50% higher.

Claims (5)

01 ΊΑ 91 patent claims: 1. A process for the preparation of a detergent powder containing a synthetic active detergent compound and an organic builder, with the formation of an aqueous slurry of the detergent ingredients and subsequent spray drying of the slurry, characterized in that the slurry contains no more than about 40% by weight of water and formed in a pressure-tight vessel at a temperature of about 125 ° C to 180 ° C, and then is spray dried in a gas stream at a temperature of about 100 ⁰ C to about 250 ⁰ C. Z The method according to claim 1, characterized in that the detergent powder is at least about Contains 50% by weight of organic material 3. Process according to the preceding claims, characterized in that the water content of the slurry is no more than about 30% by weight. 4. The method according to the preceding claims, characterized in that the gas temperature is about 150 ° C to 200 ° C 5. The method according to the preceding claims, characterized in that the organic Builder in the slurry by neutralizing the corresponding organic acid, or by Hydrolyzing and neutralizing the corresponding organic anhydride is formed.