IL44352A - Preparation of non-dusty easily wetted and readily soluble granulates - Google Patents

Abstract

1474112 Preparing dye granulates and granular detergents CIBA-GEIGY AG 15 March 1974 [16 March 1973 25 Feb 1974] 11684/74 Headings C4P and C5D [Also in Divisions A2 A5 B1 C2 and C3] Granulates of a substance, e.g. a dyestuff or a detergent, are prepared by suspending the substance in a first liquid in which it does not dissolve, adding a second liquid which at least partly dissolves the substance, the first and second liquids being either immiscible or only partially miscible, in an amount so as to form a multiphase system and subjecting the resulting system to turbulence such that agglomerates of the substance are formed (see Division B1). Granulates of dyestuff, e.g. basic, acid, sulphur, vat, mordant, chrome and disperse dyestuffs, pigments and direct dyestuffs, or granulates of a heavy duty or nonionic detergent may be prepared by the above process. [GB1474112A]

Description

o'patto OJ'RW ,oan »Vpi The: preparation of non-dusty, easily x^etted and readily soluble granulates c. 42525 The invention relates to processes for the preparation of non-dusty, easily wetted and readily soluble granulates of any desired size, from a multiphase system, as well as to the non-dusty, easily wetted and readily soluble granulates, as an industrial product, prepared by application of these processes.

Certain commercial forms of solid substances are up to the present being marketed in the form of normally dried and finely ground powders, or as spray-dried microgranulates . Both types, however, have the disadvantage that, to a greater or lesser extent, they release dust; moreover, in consequence of poor wetting, their rate of dissolving is in many cases too low for the modern requirements of industry, a factor which in part renders necessary long operational times for the preparation of solutions, or the use of expensive stirring equipment. Attempts have therefore been made to improve wetting by the addition of wetting agents, particularly in dyestuff preparations.

The changeover from the conventional drying method to spray drying enables in certain cases, with identical composition of the product, wetting to be improved: in other cases, however, it is worsened. The microgranulates produced in industrial spray driers mostly have moreover a very wide range of particle sizes, with a considerable proportion of fines . This high proportion of fines is unfavourable not merely on account of the resulting tendency for the formation of dust to occur, but also on account of the resulting impairment of the wettability of these powders due to the formation of lumps when the powders are introduced into a liquid. Furthermore, it has been shown that spray-dried granulates are in many cases not sufficiently stable mechanically, and disintegrate during storage and, in particular, during transport, with a further creation of dust occurring. These disadvantages have been known for some time in foodstuff technology; methods have therefore been developed to eliminate the proportion of fines, one method being, e.g. the subsequent agglomeration of the powders in special apparatus.

Efforts have naturally been made for a long time in the case of dyestuffs too, with a varying measure of success, to separate the fine fractions and to return them to the drying process. It has however hitherto not proved possible, without very high expenditure in equipment or high losses, to obtain by spray drying a relatively coarse granulate giving a narrow particle-size distribution curve.

In recent times, therefore, efforts have been directed towards conversion of products, e.g. by compacting or extrusion, into actual granulates having a particle size of 1 mm or more. With suitable composition, the resulting granules can have such a high degree of strength that they do not form dust, even after prolonged intensive shaking.

But they have the disadvantage that their dissolving rate is low, attaining, however, in the most favourable case the values given by the corresponding powders. < A more recent commercial, method for the preparation of non-dusty, readily soluble powders is vacuum freeze drying. This however produces products having poor free-flowing properties and, for reasons of cost, is suitable only for expensive products.

It is also known that barium sulphate suspended in fine dispersion in hydrous benzene can be agglomerated by shaking to form larger particles.

A number of processes have been proposed for the spherical agglomeration of finely divided solids suspended in a liquid. Thus, U.S. Patent No. 3,268,071 describes a process for the separation of mixed solid particles from a liquid suspending medium by spherical agglomeration wherein the finely divided solids in liquid suspendant are, if necess-arey, rendered lyophobic to the suspendant liquid. A binding or agglomerating liquid immiscible with the liquid suspendant is added to the suspension, which is then agitated to form the agglomerates.

U.S. Patent 3,368,004 describes a process for preparing spheres of powder materials, primarily refractory metal compounds, in a two phase liquid, the first liquid being inert and the second having a preferential affinity for the powder and being immis- U.S. Patent No. 3,471,267 describes a spherical agglomeration process wherein a finely divided single solid material is continuously added along with a suspending liquid and an agglomerating liquid immiscible with the first liquid, into a body of these substances in an inclined, open topped, cylindrical rotating vessel.

The second liquid constitutes a binding medium to give the particles sufficient wet strength to withstand tumling action and strength in the dried product.

Finally, Canadian Patent No. 911,737 provides an apparatus for ball agglomerating particulate material from a mixture of the material, a liquid suspendant, and an agglomerating liquid immiscible with the liquid suspendant.

In all of these ball agglomerating processes the stability of the granules is unsatisfactory or a binding medium is necessary to provide the particles with sufficient stability.

Surprisingly, it has now been found that it is possible by wet granulation to obtain mechanically very stable granulates of any desired size which are non-dusty but nevertheless easily wettable, and which possessthe unexpected property of "instant" response on application.

The process for the preparation of granulates having the said properties is characterised in that the substance to be granulated is suspended in a liquid or mixture of liquids which does not dissolve that substance, and an addition then made to this suspension of small amounts of a second liquid* or- mixture of liquids that preferentially wets or dissolves the said substance and is only partially miscible with the first-mentioned liquid, so that a multiphase system is formed and the mixture thereupon turbulently - 4b - mixed until agglomerates of the said substance form, which are subsequently separated from the liquid multiphase system and dried.

As substances to be granulated, it is possible to use all those which can be granulated by the process according to the invention; they can be homogeneous substances or mixtures of substances . These accordingly belong to the most diverse classes of substances: they are, for example, dyestuffs, optical brighteners or textile auxiliaries, pharmaceutical products, pest-control agents, foodstuffs, such as coffee, milk or flour; antimicrobial agents and bacteriostatics; detergents, paper auxiliaries (e.g. sizing agents), photographic chemicals, leather chemicals, plastics and additives for plastics. It is clear that the substances specially concerned are those which are readily wettable to soluble in one of the two liquids. These substances can be pure, or they can also contain extenders, e.g. salts or further components .

By dyestuffs are meant in the present case those of all possible classes, both coloristically and chemically, which are suitable for an aqueous and organic application. The following examples are given: basic dyestuffs, acid dyestuffs, sulphur dyestuffs, vat dyestuffs, mordant dyestuffs, chrome dyestuffs, disperse dyestuffs, pigments and, in particular, direct dyestuffs, whereby these dyestuffs can contain fibre-reactive groups in the molecule. - 5 - Also included are obviously foodstuff-colouring agents and, for example, leather dyestuffs .

The dyestuffs concerned from the chemical point of view are, for example, nitroso, nitro, monoazo, disazo, trisazo, polyazo, stilbene, carotenoid, diphenylmethane, triarylmethane, xanthene, acridene, quinoline, methine, thiazole, indamine, indophenol, azine, oxazine, thiazine, lactone, aminoketone, hydroxyketone, anthraquinone , indigoid and phthalocyanine dyestuffs, as well as 1:1- or 1 : 2-metal-complex dyestuffs.

Applicable optical brighteners, used for white tinting, are those of any desired classes of brighteners; for example, they are stilbene compounds such as cyanuric derivatives of 4,4 ' -diaminostilbene-2 , 2 ' -disulphonic acid or distyryl-biphenyls , coumarins, benzocoumarins , pyrazines, pyrazolones, oxazines, mono- or dibenzoxazolyl or mono- or dibenzimidazolyl compounds, as well as naphthalic acid imides, naphthotriazole and v-triazole derivatives.

By textile auxiliaries are meant chemicals required in the processing of the various textile fibres into finished fabrics: thus, e.g. raw wool detergents, lubricants, sizing agents, milling agents, impregnating agents, preserving agents, finishing agents, desizing agents, kier-boiling agents, bleaching agents, dyeing agents such as dispersing agents and levelling agents, - 6 - printing auxiliaries, carbonising agents, mercerising agents, preparations for the acquirement of resistance to creasing and to shrinkage, and antistatic preparations.

Pest-control agents are in general known: they serve, for example, to effect the destruction of plant pests (e.g. fungicides, insecticides, acaricides, nematicides, molluscicides and rodenticides) and the prevention of plant diseases.

By antimicrobics are meant antimicrobial substances which are intended to, or serve to, retard or prevent disadvantageous changes caused by microorganisms in foodstuffs.

Bacteriostatics are substances which inhibit or prevent the growth of bacteria.

Detergents are substances which are -synthesised, e.g. from (a) a wash-active synthetic substance, a washing raw material, (b) a washing auxiliary (detergent additive), (c) special additives, such as sodium perborate, magnesium silicate, optical brighteners, wetting agents, etc. and ψ (d) extenders. Both the detergent as such and the individual constituents thereof can be granulated according to the invention .

And, finally, plastics can be granulated; by these are meant macromolecular organic compounds obtained by the conversion of natural products or by synthesis, whereby plastic compounds are also included. - 7 - All these substances can be used according to the invention in the pure form or in the commercial form or in the form of dried or moist press cakes for the preparation of granulates. Advantageously, they are in the form of powders ground as fine as possible; they can, however, also be in the form of suspensions, such as are obtained, e.g. after synthesis. The process is likewise applicable, for example, to flocculated sediments, such as those occurring in waste-water purification.

The substance to be granulated is present advantageously in amounts of 1 to 150%, relative to the first liquid.

Liquids not dissolving the substances to be granulated, i.e. those used as the first liquid, are either water or organic liquids, or mixtures of organic liquids.

A suitable second liquid, which preferentially wets to dissolves the substance to be granulated, is an organic liquid immiscible with water, or a mixture of such organic liquids, in the case where the first liquid is water, and water and/or another liquid immiscible with the first liquid, such as an organic liquid or a mixture of such organic liquids, in the case where the first liquid is an organic liquid or a mixture of organic liquids. Hence, there are principally three possibilities; namely: a) 1st liquid : water, 2nd liquid : organic liquid or mixture of organic liquids; - 8 - b) . 1st liquid : organic liquid or mixture of organic liquids, 2nd liquid : water; c) 1st liquid : organic liquid or or mixture of organic liquids, 2nd liquid : as defined, an organic liquid different from the 1st liquid, or mixture of such organic liquids.

The best results are obtained with variant b) .

The requirements to be satisfied by the organic liquids used to effect granulation are dependent on the nature of the particular substance to be granulated. These organic liquids are, for example, alcohols such as 2-ethyl-l-hexanol, 1, 3-dichloro-2-propanol, ethanol and butanol;. aliphatic hydrocarbons, both open-chain and ring-shaped, such as n-hexane and ligroin or cyclohexane; aromatic hydrocarbons such as benzene and toluene; halogenated aliphatic hydrocarbons such as carbon tetrachloride, methylene chloride, chloroform and perchloro-ethylene, or mixed halogenated hydrocarbons, such as those known under the trade name of "Frigen", e.g. trichloro-trifluoroethane (Frigen 113 CR) , as well as esters, such as acetic acid ethyl ester. Also applicable, as defined, are mixtures of organic liquids, advantageously in the mixture ratio of 1:1, such as, e.g. a mixture of dimethyl-sulphoxide and l,3-dichloro-2-propanol . - 9 - The second liquid is advantageously employed in amounts of 1 to 60%, particularly 2.5 to 10%, relative to the first liquid; or in amounts of 10 to 90%, particularly 15 to 50%, relative to the amount of substance. These mixture-ratio amounts should be largely adhered to since in the case of excessive deviations, especially upwards, undesirable continuous masses of substance could otherwise form.

Optionally, auxiliaries may be added to the second liquid, such as, in. particula , bonding agents; and/or wetting agents, diluting agents, effervescent agents, solubilising agents, dispersing agents, acids or alkalis.

It is especially the bonding agents which serve, above all to increase the mechanical strength of the granules . Such bonding agents to be mentioned are: polyvinyl alcohol, cellulose derivatives, such as carboxymethylcellulose and hydroxypropylcellulose, polyvinylpyrrolidone and also dextrine The process according to the invention is such that the substance to be granulated is suspended, with stirring, in a liquid or mixture of liquids not dissolving the said substance, and an addition then made, in the defined quantity ratio, of a second liquid or mixture of liquids which in either case is immiscible with the first liquid, and which preferentially wets to dissolves the said substance, to thus form a multiphase system, and the resulting mixture then brought into a state of intense turbulence.

This is created, for example, by vigorous stirring movements, by use of a vibromixer, or by treatment in - 10 - a shaking machine or Turbula.

Under these conditions, with creation of a suitable state of turbulance in the suspension, the second liquid or mixture of liquids must be added in such a manner that firstly the surface of all primary particles is coated therewith. Only thus is there obtained, by a precisely dosed amount of the second liquid, a complete agglomeration. There are then formed in the multiphase system substance-agglomerates having a fairly homogeneous particle distribution. Their size is governed by the quantity ratio of the second liquid to the substance.

. These agglomerates are subsequently separated from the liquid multiphase system by a manner known per se e.g. by filtration under suction or by normal filtration, and dried by known methods.

A preferred embodiment comprises, for example, the suspension or dispersion of four parts of dyestuff, optical brightener, textile auxiliary, bacteriostatic agent, washing raw material and detergent, paper auxiliaries or leather chemicals in 8 parts of an organic liquid, e.g. a mixed halogenated hydrocarbon such as trichlorotrifluoro-ethane; and the addition continuously, with thorough turbulent mixing by means of a stirring or mixing apparatus, of 1 part of water; and the subsequent intensive mixing together of this mixture until agglomerates form in the three-phase system. - 11 - In a modification of the process1., the substance to be granulated is added to a multiphase system consisting of a liquid or mixture of liquids not dissolving the said substance and a second liquid or mixture of liquids which wets to dissolves the substance on its own, and which is immiscible with the first liquid, the addition being made continuously, with stirring and subsequent turbulent mixing, in such a manner that agglomerates of the said substance are formed, which are afterwards separated from the multiphase system and dried.

The details initially given with regard to the substance to be granulated and to the liquids apply where appropriate for this modification too.

There are obtained by these processes, the surprising factor of which is that on application to water-soluble substances or to organosoluble substances these do not dissolve in the aqueous or organic phase, but precipitate from the two- phase or multiphase system, granulates which can have the most diverse forms, such as, for example, spherical, lenticular, elongated or rod-shaped. The diameter of these forms is preferably 50 to 500 microns, with the granules being of a very uniform size. These granulates are surprisingly of such a nature that, compared with the corresponding powder forms, they have a much higher rate of dissolving or more rapid dispersibility, - 12 - particularly in cold water and hot water, and, furthermore, that they do not create dust and are moreover very readily wettable; they are also very free flowing, and have a high bulk weight. It is possible in this manner to obtain from soluble substances granulates having "instant" properties, i.e. their decomposition in the solvent medium is instantaneous. Also to be emphasised is the high mechanical stability of the said granulates .

The yield of these granulates can amount to up to 100%. With the correct choice of liquids, granulation is in most cases complete, with the result that there is a clear separation of the liquid phase .from the solid phase .

The following examples are intended to illustrate the invention without in any way limiting the scope thereof. The granulates obtained can in general be easily dispersed or dissolved in their application medium without the use of special stirring devices. - 13 - Example 1 An amount of 4 parts by weight of the dyestuff of the formula is added to 20 parts by volume of 2-ethyl-l-hexanol, and a suspension obtained by vigorous shaking in a Turbula.

Two parts by volume of water are then added to the suspension, and shaking of the mixture is continued.

After a shaking time of 15 minutes, spherical dyestuff-agglomerates of 0.5 to 1 mm diameter are obtained: these are separated from the two- phase system by filtration, and dried to obtain a light-brown dyestuff granulate which is very free flowin non-dusty, easily wetted and readily soluble in cold water.

If, instead of 20 parts by volume of 2-ethyl-l-hexanol, identical parts of trichlorotrifluoroethane, carbon tetra-chloride, n-hexane, ethyl acetate, methylene chloride, benzene, chloroform or cyclohexane are used, with otherwise the same procedure, then dyestuff granulates having similar properties are obtained. - 14 - Example 2 An amount of 4 parts by weight of the dyestuff of the formula is added to 60 parts by volume of 2-ethyl-l-hexanol, and a suspension obtained by vigorous shaking in a shaking machine. One part by volume of water is then added to the suspension, and shaking of the mixture continued for 1 hour. This procedure leads to the formation of small dyestuff globules of uniform size: these are separated from the two-phase system and subsequently dried. An ochre-yellow dyestuff granulate is obtained which is very free flowing, non-dusty, easily wetted and readily soluble in cold water. - 15 - Example 3 An amount of 4 parts by weight of the dyestuff of the formula is added to 20 parts by volume of carbon tetrachloride, and a suspension obtained by vigorous shaking in a .

Turbula (shaking machine) for 20 minutes. 1.5 Parts by volume of water are added to this suspension, and the mixture is subsequently shaken for 40 minutes . Lenticular dyestuff-agglomerates of 0.5 to 1 mm diameter are obtained: these are separated from the two- phase system by filtration, and dried to obtain a yellow dyestuff granulate which is very free flowing, non-dusty, easily wetted and readily soluble in cold water. - 16 - Example 4 An amount of 4 parts of the dyestuff of the formula (pure material) is added to 20 parts by volume of n-hexane, and a · suspension obtained by shaking of the whole for 12 minutes in a shaking machine. One part by volume of water is added to the suspension, and the mixture then shaken for 40 minutes. Spherical to elongated dyestuff-agglomerates of 0.5 to 3 mm diameter are obtained: these are separated from the two-phase system by decanting, and dried to obtain a reddish-violet dyestuff granulate which is very free flowing, non-dusty, easily wetted and readily soluble in cold water.- - 17 - Example 5 An amount of 4 parts by weight of an optical brightener of the formula is added to 20 parts by volume of n-hexane, and a suspension obtained by vigorous shaking of the whole for 5 minutes. To this is added 0.5 part by volume of water, and the mixture then shaken for 20 minutes.

Spherical agglomerates of 0.5 to 3 mm diameter are obtained: these are separated from the two- phase system, and dried to give an optical brightener granulate which is very free flowing, non-dusty, easily wetted and readily soluble in cold water.

If the optical brightener employed is one of the formula this being suspended in perchloroethylene and granulated with water, the procedure otherwise remaining the same, then equally good granulates are obtained. - 18 - If the optical brightener employed is one of the formula this being suspended in cyclohexane and granulated with water, the procedure otherwise remaining the same, then equally good granulates are obtained.

If the optical brightener employed is one of the formula this being suspended in water and granulated with tolueiie, the procedure otherwise remaining the same, then equally good granulates are obtained. - 19 - Example 6 An amount of 4 parts by weight of the dyestuff of the formula (dried press cake) is added to 20 parts by volume of n-hexane, and a suspension obtained by vigorous shaking of the whole for 20 minutes. To this is added 0.5 part by volume of water, and the mixture then shaken for one hour. Spherical dyestuff agglomerates of about 1 to 3 mm diameter are obtained: these are separated from the two- phase system, and dried to obtain an ochre-yellow dyestuff granulate which is very free flowing, non-dusty, easily wetted and readily soluble in cold wate . - 20 - Example 7 An amount of 4 parts by weight of the dyestuff of the formula (dried press cake) is added to 20 parts by volume of n-hexane, and a suspension obtained by vigorous shaking for 10 minutes.

An addition of 0.7 part by volume of water is made to the suspension, and the mixture shaken for a further 15 minutes. Spherical dyestuff agglomerates of about 0.5 to' 1 mm diameter are obtained: these are separated from the two- phase system, and dried to obtain a yellow dyestuff granulate which is very free flowing, non-dusty, easily wetted and readily soluble in cold"' water. ' - 21 - Example 8 An amount of parts by weight of the 'dyestuff of the formula 2:1-cobalt complex is added to 20 parts by volume of n-hexane, and a suspension obtained by vigorous shaking for 12 minutes. An addition of 1.5 parts by volume of \ One part by volume of water is added to the suspension, and the mixture shaken for a further 20 minutes .

Spherical dyestuff agglomerates of uniform si2e having a diameter of about 0.5 to 2 mm are obtained: these are separated from the two- phase system, and dried to obtain a light- brown dyestuff granulate which is very free flowing, ηοή-dusty, easily wetted and readily soluble in cold wate . - 23 - Example 10 An amount of 4 parts by weight of a dried dyestuff press cake containing the dyestuff of the formula is added to 20 parts by volume of water, and the whole vigorously shaken for 10 minutes to obtain a suspension. An addition is made to this of 2 parts by volume of ethyl acetate, and the mixture shaken for a further 20 minutes; spherical dyestuff agglomerates having a diameter of about 1 to 2 mm are obtained: these are separated from the two-phase system, and dried to obtain a dark brown dyestuff granulate which is very free flowing, non-dusty, easily wetted and readily soluble in cold water . - 24 - Example 11 An amount of 4 parts by weight of the dyestuff of the formula C-Br SCLNa I I CH2 is added, with vigorous shaking, to a two-phase system consisting of 20 parts by volume of carbon tetrachloride and. 2 parts by volume of water, and the mixture shaken in a shaking machine (Turbula) for about 40 minutes . Spherical dyestuff agglomerates are obtained: these are separated from the two-phase system, and dried to obtain a yellow dyestuff granulate which is very free flowing, non-dusty, easily wetted and readily soluble in cold water. - 25 - Example 12 An amount of 4 parts by weight of the dyestuff of the formula is added to 8 parts by volume of n-hexane, and the whole shaken vigorously for 10 minutes to obtain a suspension.

An addition is made to this of 2 parts by volume' of water, and shaking continued for a further 20 minutes. Spherical dyestuff agglomerates are formed having a diameter of 1 to 2 mm: these are separated from the two- phase system, and dried to give a light-brown dyestuff granulate which is very free flowing, non-dusty, easily wetted and readily soluble in cold water. The bulk weight of these granulates is 0.7, and is appreciably higher than that of spray-dried dyestuff. - 26 - Example 13 An amount of 4 parts by V7eight of the dyestuff of the formula is added to 20 parts by volume of commercial benzene, and the whole vigorously shaken to obtain a suspension. An addition is made to this of 1 part by volume of water, and this mixture shaken in a shaking machine (Turbula) . After a shaking time of 30 minutes, spherical dyestuff agglomerates of about 0.5 to 1 mm diameter are formed: these are separated from the two- phase system, and dried to give a red dyestuff granulate which is very free flowing, non-dusty, easily wetted and readily soluble in cold water. - 27 - Example 14 An amount of 4 parts by weight of the dyestuff of the formula is added to 20 parts by volume of trichlorotrifluoro-ethane (Frigen 113 CR) , and the whole vigorously shaken to obtain a suspension, to which is then added 1 part by volume of water. After a shaking time of 30 minutes, spherical dyestuff agglomerates of ca. 0.5 to 1.5 mm in diameter are formed: these are separated from the two- phase system, and dried to give a light-brovm dyestuff granulate which is very free flowing, non-dusty, easily wetted and readily soluble in cold water. - 28 - An amount of 4 parts by weight of the dyestuff of the formula is added to 20 parts by volume of n-hexane, and the whole vigorously shaken to obtain a suspension. One part by volume of water is added to this, and the mixture shaken in a shaking machine (Turbula) . After 30 minutes' shaking time, rod-shaped dyestuff agglomerates of ca. 0.5 mm diameter are formed: these are separated from the two- phase system, and dried to give a yellow dyestuff granulate which is very free flowing, non-dusty, easily wetted and readily soluble in cold water. - 29 - Example 16 An amount of 4 parts by weight of a textile auxiliary (dinaphthylmethane-disulphonate) is added to 20 parts by volume of 2-ethyl-l-hexanol, and the whole shaken vigorously in a shaking machine (Turbula) to obtain a suspension; to this are added 2 parts by volume of water,. nd shaking of the mixture is continued. After a shaking time of 15 minutes, spherical agglomerates of 0.5 to 1 mm diameter are formed: these are separated from the two- phase system by filtration, and dried to give a granulate which is very free flowing, non-dusty, easily wetted and readily soluble in cold water . - 30 - Example 17 To 40 parts by weight of Frigen 113 are added 5 parts by weight of a fungicide of the formula and the whole is vigorously shaken for 5 minutes to obtai a suspension. An addition is made to this of 2 parts by volume of water, and the mixture then shaken for 10 minutes. Spherical agglomerates of the fungicide are obtained, which are subsequently separated and dried.

Example 18 4 Parts by weight of the pharmaceutical agent 3- (4-methyl-l-piperazinyl-iminomethyl) -rifamycin SV are added to 20 parts by volume of Frigen 113, and the whole is vigorously shaken for 2 minutes to obtain a suspension; an addition is made to this of 2 parts by volume of aqueous IN hydrochloric acid solution, and the mixture shaken for 10 minutes . Spherical agglomerates of the pharmaceutical agent are obtained, which are then separated and dried. - 31 - Example 19 5 Parts by weight of the pharmaceutical agent 1- (2-allyloxy-phenoxy) -3-isopropylamino-2-propanol are added to 25 parts by weight of Frigen 113, and the whole is shaken vigorously for 2 minutes; a suspension is thus obtained and to this are added 4 parts by weight of water; the whole is shaken for 3 minutes to obtain spherical agglomerates, which are subsequently separated and dried.

Example 20 50 g of a finely powdered, heavy-duty detergent containing 16 g of the sodium salt of dodecylbenzene-sulphonate, 4 g of fatty alcohol sulphate, 3 g of coconut fatty acid monoethanolamide, 40 g of tripoly-phosphate, 4 g of sodium disilicate, 2 g of magnesium silicate, 1 g of carboxymethylcellulose , 0.5 g of Sequestrene ST, 5 g of water and 24.5 g of sodium sulphate are dispersed in butanol in the course of 5 minutes by means of a powerful stirrer. An addition is then made slowly, with stirring, of about 40 ml of water: this results in the formation of spherical agglomerates of the detergent, which are filtered off. The dried product is non-dusty, easily wetted, and readily soluble in water. 32 - Example 21 20 g of a pulverulent, nonionic detergent containing 4 g of nonylphenol added to 3 to 6 moles of ethylene oxide, 4 g of nonylphenol added to 9 to 10 moles of ethylene oxide, 4 g of Alfol C^^_^g added to 25 moles of ethylene oxide, 3 g of sodium soap, 50 g of sodium tripolyphosphate, 5 g of sodium disilicate, 2 g of magnesium silicate, 1 g of carboxymethylcellulose, 10 to 12 g of sodium sulphate, 5 g of sodium carbonate and 10 to 12 g of water is suspended in 50 g of ligroin (80 to 110°C) . An amount of 8 ml of water is then stirred in by means of vigorous stirring; the result is the formation of small spherical agglomerates of the detergent, which, after drying, are non-dusty, easily wetted in water and soluble.

Example 22 18.5 g of finely ground coffee is suspended in ligroin (80 to 110°C) . There is then continuously added, with vigorous stirring, 7.5 g of a mixture of 9 parts of ethanol and 1 part of water. The resulting coffee granulate is filtered off and dried. A granulate is thus obtained which is instantly soluble in cold water (Instant Coffee).

Equally good results are obtained with extracted coffee powder.

Example 23 100 g of spray dried milk powder (skim milk base powder) - 33 - is suspended in 300 g of ligroin (80 to 110°C) . An addition is then made dropwise, with vigorous stirring (500 r.p'.m.), of 28 ml of water. Easily filterable granulates are thus obtained, which, after drying, readily dissolve in cold water .

Example 24 20 g of flour is suspended in 60 g of ligroin (80 to 110°C); to this suspension there is then added dropwise, with vigorous stirring, 6 to 7 ml of 1,3-dichloro-2-propanol; this results in the formation of small to medium- sized agglomerates which, after drying, give a non-dusty flour granulate.

Example 25 100 g of a cation-active melamine- formaldehyde-resin (paper-sizing agent) is suspended in 500 g of Frigen 113, and to the suspension is slowly added dropwise, with vigorous stirring, 20 ml of 1 , 3-dichloro-2-propanol .

There are thus formed spherical granulates, which are dried on a glass frit with compressed air.

Identical granulates of similar quality are also obtained by the addition dropwise, with stirring (ca. 700 r.p.m.) of 18.5 ml of l,3-dichloro-2-propanol to 100 g of cation-active melamine-formaldehyde-resin suspended in 500 g of ligroin (80 to 110°C) . There are thus formed small spherical agglomerates, which are dried on a glass frit by compressed air. - 34 - Example 26 5 g of the antimicrobial agent of the formula is suspended in 50 g of water; there is then made, with stirring, a dropwise addition continuously of about 6 ml of ligroin (80 to 110°C) . There are thus formed small spherical agglomerates, which can be easily dried to obtain the corresponding non-dusty granulates of the antimicrobial agent.

Granulates of similar quality are obtained by the slow addition dropwise, with stirring, of about 18 ml of n-butanol to 10 g of the above antimicrobial agent suspended in 100 ml of water. The resulting agglomerates are spherical to angular in shape.

Example 27 35 g of moist dyestuff press-cake containing the dyestuff of the formula is stirred into 60 g of n-butanol for about 10 minutes. - 35 - There is subsequently added, with stirring (ca. 1000 r.p.m.), 100 g of Frigen 113; an addition is then slowly made dropwise, to effect agglomeration, of 6.7 g of water.

Agglomerates are thus formed, which are separated, and afterwards dried in a drying cupboard at 50°C obtain the corresponding dyestuff granulates, which dissolve very rapidly in water.

Example 28 8.5 to 9 ml of water is added dropwise, in the of about 15 to 20 minutes, to 30 g of the dyestuff the formula suspended in 90 g of Frigen 113. There occurs the formation agglomerates, which are then separated from the multiphase system, and dried at 50°C in a drying cupboard to give dyestuff granulates readily soluble in water.

Example 29 6 g of water is added dropwise in the course of about 15 minutes, with stirring, to 20 g of the dyestuff of the formula - 36 - in 60 g of Frigen 113. This results in the formation agglomerates, which are subsequently dried on a glass frit with compressed air to obtain dyestuff granulate which are very readily soluble in water. - 37 - Example 30 50 g of the powdered dry dyestuff, of a self-condensation product of p-nitrotoluene-2-sulphonic acid in 100 g of n-butanol (suspension liquid) are put into a reaction vessel. After stirring for app. 5 minutes (app . 500 rprn) at room temperature, 33 ml of water are added dropwise to the homogeneous suspension at the same stirring speed using a drip funnel. Stirring is then continued for app. 30 minutes, after which time the agglomeration is terminated. The precipitated dyestuff granulate is separated using an aspirator and a Bllchner suction filter and dried at 50° in vacuo .

Yield: 50 g of the above dyestuff in granulate form. It is characterised by a fairly homogeneous granulometry in the range of app. 200 to 600 microns and contains no fine dust. When added to water, the granules are wetted momentarily and dissolve very rapidly.

Example 31 100 g of an aqueous filter ca,ke (33% solids and 677» water) of the same dye as used in Example 30 is converted into a thin, homogeneous suspension by adding 250 g of n-butanol with Homorex, and granulation is also effected during the slow addition of app. 1 ml of^water with good stirring at room temperature.

Stirring is continued for app. 30 minutes to bring the agglomeration to completion and to harden the particles. The granulate - 37a - precipitates. It is collected using an aspirator and a BUchner suction filter and dried at 60° in vacuo. Yield: 33 g of the dyestuff in granulate form.

Example 32 200 g of Freon-113 TR (1 , 1 , 2-trichloro-l , 2 , 2-trifluoroethane) and 20 g of the fluorescent brightener of the formula are put into a reaction vessel. After stirring for app. 5 minutes (app . 700 rpm) at room temperature, app. 28 ml of 1 ,3-dichloro-2-propanol are added dropwise at the same stirring speed using a drip funnel. The granulation is terminated about 30 minutes later. The fluorescent brightener granulate is isolated using an aspirator and a BUchner suction filter and dried in vacuo at 50°.

Yield: app. 20 g of the above fluorescent brightener in granulate form.

Example 33 i 10 g of a powdery condensation product of formaldehyde and urea are put into a reaction vessel in 60 g of ethyl methyl ketone. After stirring fo app. 5 minutes (app. 700 rpm) at room temperature, 40 ml of water are slowly added dropwise' to the viscous suspension at the same rate of stirring using a drip funnel. Granules are obtained which are filtered off after brief stirring in vacuo and dried at 50° in a vacuum drier.

Yield: 10 g of the condensation . product in granulate form.

Example 34 With stirring (app. 800 rpm) , 115 g of an aqueous suspension of 5.7 g of the condensation product of Example 33 are run into 300 g of n-butanol at room temperature in the. course of app. 10 minutes. Granules are formed during this operation. When the filtrate is clear, the granulation is terminated. The granules are filtered off in vacuo and dried at 50° in a vacuum drier.

Yield: 5.7 g of the condensation product in granulate form.

A yield of 6.5 g of condensation product in granulate form is obtained by using 200 g of sec. butanol instead of the 300 g of n-butanol and 130 g instead!of 115 g of the above aqueous suspension and otherwise carrying out the described procedure in analogous manner. | ' · i Example 35 '[·' With stirring, 220 g of an aqueous filter sludge (18% solids content) from a purification -plant are added at room temperature to 500 ml of n-butanol. jGranules form which, after brief stirring, are filtered off in -vacuo and dried at 50° in vacuo. Yield: 39.5 g of dry sludge granulate. - 37c - Example 36 With stirring (app . 500 rpm), app . 300 g of n-butanol are rapidly run into 150 g of aqueous activated sludge. Granules form which are filtered off in vacuo after stirring for 30 minutes and dried at 50° in a vacuum drier. Yield: 6 g of granulate .

Example 37 A suspension of 50 g of aqueous filter cake (44% solids content and 66% water) , which contains as solid the dye of formula and 80 g of ethanol is prepared at room temperature with stirring. This suspension is added slowly to 150 g of Freon-113 TR at room temperature with stirring (app. 500 rpm), whereupon dye-stuff granules form after a time. The dyestuff granules are isolated fusing an aspirator and a BUchner suction filter and dried injvacuo. Yield: app. 20 g of dyestuff granulate.

An equally good granulate is obtained by using instead of Freon-113 TR and ethanol equal amounts of acetorie/Freon-113 TR or diacetrone alcohol/Freon-113 TR or a mixture of methyl acetate, ethyl acetate, methanol and n-butanol or a mixture of methyl acetate and methanol, and otherwise carrying out the same procedure. . ' *. - 37d - Example 38 33 g of aqueous filter cake (33?0 solids content, consisting of the dyestuff of Example 1 and salt, and 6TL water) are very slowly made into a paste with 17 g of n-propanol. Granules gradually form in the liquid two-phase system and these deposit. They are filtered off and dried at 40° in vacuo to yield 10 g of dyestuff granulate.

Example 39 With cooling, 18 g of isobutanol are added to 100 g of a ground suspension (particle size < 5 p) consisting of 78 g of water and 22 g of the dyestuff of formula .

After stirring :for app . 15 minutes, the suspended particles have been completely converted into granules .

The granules are isolated and dried at 60°. They are used for manufacturing organic printing inks for transfer printing on polyester. 1 Example 40 With stirring, 0.8 g of dextrin (270 referred to solids) is dissolved in 220 g of an aqueous filter cake (18% solids content) from a purification plant. The sludge is added with stirring at room temperature to 500 ml of n-butanol. After brief stirring, 37e granules are obtained which are filtered off in vacuo and vacuum dried at 50°. There are obtained about 40 g of a very hard and dry sludge granulate.

Example 41 20 g of 1,3 ,4 , 6-tetraacetylglycoluril of formula are suspended in 320 g of Freon-113 TR. To the suspension are slowly added with further stirring 12 ml of l,3~dichloro-2-propanol. Small to medium large granules are formed which are dried at 50°. The dried granules are hard and dust-free.

Example 42 29 g of K2CO2 are dissolved in 100 g of an aqueous synthesis suspension of the dyestuff of formula (257o dyestuff content). With stirring, 5 g of acetone are added thereto. After app . 10 minutes granules form from the liquid two-phase system. The completely precipitated! dyestuff granules are isolated using an aspirator and a BUchner j suction filter and dried at 50° in vacuo. Yield; 25 g of the above dyestuff in granulate form. . 1 ·

Claims (19)

44352/2 CLAIMS :

1. A process for the preparation of non-dusty, easily wetted and readily soluble granulates which comprises exposing the substance to be granulated to a liquid system consisting of a first liquid component which does not dissolve the substance and a small amount of a second liquid component which wets or dissolves the substance, and which second liquid is partially miscible with the first liquid component, and mixing the multiphase system so produced to form granules of the substance and subsequently separating the granules from the liquid system.

2. A process as defined in Claim 1 wherein the mixing is carried out turbulently.

3. Process according to Claims 1 and 2, wherein the substance to be granulated is present in amounts of 1 to 150%, relative to the first liquid.

4. Process according to Claims 1 to 3, wherein the second liquid is used in amounts of 1 to 60%, particularly 2.5 to 10%, relative to the first liquid, or in amounts of 10 to 90%, particularly 15 to 50%, relative to the amount of substance to be granulated. - 38 - 44352/2

5. Process according to Claims 1 to 3, wherein the employed substances to be granulated are dyestuffs, optical brighteners, textile auxiliaries, pharmaceutical products, pest-control agents, foodstuffs, antimicrobial agents, bacteriostatics, detergents, paper auxiliaries, photographic chemicals, leather chemicals, plastics and additives for plastics.

6. Process according to Claim 5, wherein there is used, as the substance to be granulated, a homogeneous substance or mixture *of substances, in commercial form or in the pure state, as a dried or moist press cake or as a suspension of the said substance.

7. Process according to Claims 1 to 6, wherein the employed first liquid not dissolving the substance to be granulated is water, or an organic liquid or a mixture of organic liquids possessing the said property,

8. Proce&s according to Claims 1 to 6, wherein the employed second liquid which wets to dissolves the substance to be granulated is an organic liquid or mixture of organic liquids in the case where the first liquid is water, or water and/or an organic liquid immiscible with the first liquid in the case where the first liquid is an organic liquid. - - \ 44352/2

9. '9. Process according to Claims 7 and 8, wherein the employed organic liquids are alcohols such as 2-ethyl-l- hexanol; halogenated aliphatic hydrocarbons such as trichlorotrifluoroethane; as well as esters such as acetic acid ethyl ester.

10. Process according to Claim 8, wherein an organic liquid or a mixture of organic liquids is used as the first liquid, and water as the second liquid.

11. Process according to Claims 1 and 2, wherei auxiliaries are added to the second liquid, such as, in particular, bonding agents and/or wetting agents, diluting agents, effervescent agents, solubilising agents, acids and bases or dispersing agents.

12. A process according to any one of the preceding claims, wherein two liquids are used which are partially miscible with each other.

13. A process according to Claim 12, wherein one of the two liquids is water and the other is butanol or 2-ethyl-l- hexanol .

14. A process according to Claim 12, wherein one of the two liquids is 1 , 1 , 2-trichloro-l , 2 , 2-trifluoroethane and the other is 1 , 3-dichloro-2-propanol .

15. A process according to any one of the preceding claims wherein the substance to be granulated is a flocculated sediment, such as occurring, for example, in waste-water purification. 44352/3

16. The non-dusty, easily wetted and readily soluble or dispersible granulates obtained according to the processes of Claims 1 to 14.

17. A process substantially as described in any one of the foregoing Examples 1 to 16.

18. A proces substantially as described in any one of the foregoing Examples 17 to 42.

19. A method of producing granulates substantially as hereinbefore described. HE:dn