The method of preparation for the choline chloride powders of this invention

This invention is concerned with a powdered form of choline chloride which has a higher choline chloride content than hitherto known with retention of desirable flow and storage properties, and a process for producing this product.

Choline chloride chemically is (2-hydroxyethyl)trimethylammonium chloride. It is a source of choline which is one of the vitamin B-complex. It finds commercial use as a nutritional factor, primarily as a dietary supplement for poultry and swine, and for pharmaceutical applications. The compound in the pure, anhydrous state is a white, crystalline solid which is very soluble in water or alcohol. It is quite hygroscopic and very rapidly picks up enough moisture to become a syrupy liquid. Consequently, choline chloride is usually sold as a water solution-a 70% concentration is a common commercial form.

CHOLINE CHLORIDE – DIETARY REQUIREMENTS OF BROILERS

Choline supplementation in broilers shows a linear response in weight gain up to 1115mg/kg from 10-22 days of age. Increasing choline content up to 2000mg/kg further increases the weight gain but over and above this value no significant increase in weight gain was observed. Thus it could be concluded that excess level of choline supplementation had no additional benefit.

CHOLINE CHLORIDE – DIETARY REQUIREMENTS OF LAYERS

Layers, like broilers, have an essential requirement for choline. Choline is required for the formation of a phospholipid lecithin, a component of egg yolk. Current NRC recommendations for choline allowances in laying hens are 105 mg/day for white egg layers and 115 mg/day for those laying brown eggs. On an average for the two groups it can be concluded that required dietary concentration of choline at feed intake levels of 100 and 110 g/day respectively, is approximately 1100 mg/kg.
There are several factors which influence a hen’s requirement for choline, like age, feed intake and dietary crude protein or methionine levels. It is generally accepted that dietary requirement declines with age, possibly associated with an increasing feed intake. Methionine is the first limiting amino acid for egg production and, given the common function with choline in methyl group donation, interactions between the two nutrients may be anticipated. Choline requirement in layers also varies according to the methionine and cysteine levels in feed. A diet rich in M+C has low requirement of choline and vice-versa.

The following examples illustrate the method of preparation for the choline chloride powders of this invention.

EXAMPLE 1 Preparations using Diluex clay (a) Spray drying of an aqueous slurry of choline chloride and Diluex.

A slurry was prepared by mixing 970 pounds of a 63% aqueous choline chloride solution and 300 pounds of Diluex clay. This slurry Was heated to 140 F. and had a viscosity of 480 centipoises. The slurry was pumped to a 10-foot diameter spray dryer and atomized at a pressure of 1500 pounds per square inch by means of a nozzle into the dryer. The slurry, after pumping, was found to mately the same length of time. In this manner, a substantially uniform surface impregnation of the dried choline chloride particles occurred. The solid product was separated by means of a cyclone collector and discharged into a container. The following table gives details of these preparations, all of which gave a stable, dry, freeflowing choline chloride powder suitable for commercial use.

TABLE.-POWDER-ED CHOLINE CHLORIDE PREPARATIONS Introducted Into Spray Dryer Product Length Of Solids Example Choline Additive Run (min) Recovered, Choline Chloride Percent Chloride, Water, (Dry Basis) Percent Percent lbs. Kind Lbs.

12 Diluex clay 8.3 62 86 58 2.6 13. 7 (1o 4. 2 62 100 68 2. 2 18 do 5. 2 68 90 78 1.9 19 Attaclay X250. 4. 5 73 94 80 1. 1 11 Barden clay 1. 4 45 100 85 1. 6 20 Walnut shell flour 3. 5 75 94 78 1.2 14 Dilllex clay+Cab-O-Sil at 9:1 4 59 97 74 2′ 1 wt. ratio. 22 Diluex clay+Oab-O-Sil at 5. 6 100 99 75 2. 3

97.5125 wt. ratio. 19 Diluex clayd-Sodium bicarbon- 4 95 96 76 2.3

ate at 9:1 wt. ratio.

periodically blocked the flow of the product into the collecting drums and necessitated hammering on the walls to again start the flow. The dried choline chloride powder caked in the collecting drums. The amount of solid recovered from the collector represented 64% of the 912 lbs. theoretical. By cleaning out the dryer, another 15% of the solid product was recovered, thus increasing the total solids accountability to 79%. The product was found by analysis to contain 65% choline chloride.

By this method, there was ditficulty with the viscosity of the original slurry increasing, with solids adhering to the walls of the drying and collecting system, with caking of the product, and with poor yields.

(b) Spray drying by separate feeding of aqueous choline chloride solution and Diluex.

Another preparation was made in the same spray dryer and with the same drying conditions except that the choline chloride solution was atomized alone while the Diluex clay was fed directly into the top of the dryer. The clay was supplied at such a rate that approximately 1 lb. of it was fed into the dryer for every 3.2 lbs. of the choline chloride solution which was atomized. The solids on the walls of the dryer rapidly reached an equilibrium depth and flowed readily through the collecting system. No trouble was experienced in discharging the solids from the cyclone collector. The product flowed freely into the container drums and did not cake. The solid which collected in the drums amounted to 82% of the solids fed into the dryer and a partial cleaning of the dryer increased this amount to 87%. The resulting dry, free-flowing solid contained by analysis 72% choline chloride.

OTHER EXAMPLES A series of runs was made in a manner of that described in Example 1(b), but using a 4-foot diameter spray dryer. Air was passed in at the rate of 250 cubic feet per minute and entered the chamber at a temperature of about 170 to 210 C. and left it at a temperature of about 110 C. A 63% aqueous solution of choline chloride was atomized into the chamber of the spray dryer through a nozzle at a pressure of 100 pounds per square inch. The powdered additive was introduced into the top of the drying chamber near the air inlet by means of a screw-type conveyor. The rate of introduction of the two feed streams into the drying chamber was adjusted so that both materials were added in approxi- In the same manner, other aqueous choline chloride solutions up to concentration may be used and the amount of the powdered additive may be varied so that the final product contains choline chloride up to The choline chloride powders of this invention may be used alone or in admixture with other materials commonly used in animal feeds. Likewise, the powder may be shaped into other forms, such as pellets, if desired.

By means of this invention, there are provided new choline chloride powders of high choline chloride content which are essentially dry, free-flowing and stable, and which are made by a novel and economic process. Such a product fulfills a long standing commercial need.

We claim:

1. A stable, substantially dry, free-flowing powder comprising choline chloride substantially encapsulated by a powdered additive selected from the group consisting of attapulgite clay, a mixture of attapulgite clay and a second additive selected from the group consisting of silica gel and sodium bicarbonate wherein said second additive is no more than 10% of the Weight of the mixture, kaolinite clay, a mixture of kaolinite clay and a second additive selected from the group consisting of silica gel and sodium bicarbonate wherein said second additive is no more than 10% of the weight of the mixture, walnut shell flour, and a mixture of walnut shell flour and a second additive selected from the group consisting of silica gel and sodium bicarbonate wherein said second additive is no more than 10% of the Weight of the mixture, said powder containing 68% to 85% choline chloride on an anhydrous weight basis.

2. A stable, substantially dry, free-flowing powder comprising choline chloride substantially encapsulated by an attapulgite clay, said powder containing from about 68% to about 85% of choline chloride on an anhydrous weight basis.

3. A stable, substantially dry, free-flowing powder comprising choline chloride substantially encapsulated by an attapulgite clay having an average particle size of 1.6 to 1.9 microns, said powder containing from about 68% to about 85% of choline chloride on an anhydrous weight basis.

4. A stable, substantially dry, free-flowing powder comprising choline chloride substantially encapsulated by a mixture of an attapulgite clay and sodium bicarbonate wherein the sodium bicarbonate is no more than 10% of the mixture, said powder containing from about 68% to about 85% of choline chloride on an anhydrous weight basis.

5. A stable, substantially dry, free-flowing powder comprising choline chloride substantially encapsulated by a kaolinite clay, said powder containing from about 68% to about 85% of choline chloride on an anhydrous weight bas s.

6. A stable, substantially dry, free-flowing powder comprising choline chloride substantially encapsulated by walnut shell flour, said powder containing from about 68% to about 85% of choline chloride on an anhydrous weight basis.

7. In a spray-drying process for the production of a v stable, substantially dry, free-fiowing powder containing from 68% to about 85% by weight of choline chloride substantially encapsulated by a powdered additive selected from the group consisting of attapulgite clay, a mixture of attapulgite clay and a second additive selected from the group consisting of silica geland sodium bicarbonate wherein said second additive is no more than 10% of the weight of the mixture, kaolinite clay, a mixture of kaolinite clay and a second additive selected from the group consisting of silica gel and sodium bicarbonate wherein said second additive is no more than 10% of the Weight of the mixture, walnut shell flour, and a mixture of walnut shell flour and a second additive selected from the group consisting of silica gel and sodium bicarbonate whereinsaid second additive is no more than 10% of the weight of the mixture, the steps comprising (a) atomizing an aqueous choline chloride solution into the drying chamber of a spray dryer,

(b) simultaneously feeding into the drying chamber as a separate feed said powdered additive, and.

(c) collecting the choline chloride powder which has become impregnated with the powdered additive.

8. In a spray-drying process for the production of a stable, substantially dry, free-flowing powder containing from 68% to about 85% by weight of choline chloride, according to claim 7, the step wherein said powdered additive is simultaneously fed into the drying chamber with the entering air stream as a separate feed.

References Cited UNITED STATES PATENTS 2,765,231 10/1956 Plitt 992 2,879,161 3/1959 Vallentine 99-2 FOREIGN PATENTS 1,307,421 9/1962 France.

OTHER REFERENCES Chemical Abstracts, 59:447 (1963). Watkins, T. C., et al., Handbook of Insecticide Dust 25 Diluents and Carriers, Dorland (1955) p. 4.

SAM ROSEN, Primary Examiner.

S. SINGER, Assistant Examiner.