July 1, 1925 
Colloidal Clays as Emulsifiers for Mineral Oils 
61 
Mineral lubricating oil_gallon_1 
Water_do_1 
Fuller’s earth_pounds. _ 2% 
As was the case with kaolin, fuller’s earth dispersed readily in the 
water, after which the oil was added. The entire mixture was pumped 
three times, and the resulting emulsion proved satisfactory, but it 
was much thinner than where a similar proportion of kaolin was used. 
In order to test fuller’s earth further, the following formula was tried: 
Mineral lubricating oil_gallons. _ 2 
Water-do_1 
Fuller’s earth_ pounds. _ 2 % 
The entire mixture was pumped twice, resulting in a very thick 
emulsion, which when tested with water gave a little free oil, but 
further trials gave entirely satisfactory results. 
In laboratory tests kaolin and fuller’s-earth emulsions were mixed 
with practically all spray materials used in citrus groves, including 
1-1-50, 3-3-50, 5-5-50, neutral and improperly prepared Bordeaux 
mixtures as well as “hard” deep-well water, and many other solu¬ 
tions. Concentrated sulphuric, nitric, and hydrochloric acids, satu¬ 
rated caustic soda and concentrated lime-sulphur solutions had no 
appreciable effect on causing the oil to separate. 
These emulsions do not separate into layers within a reasonable 
length of time as do the soap emulsions and commercial miscible 
oils, nor do they deteriorate rapidly. Kaolin emulsion has been 
kept in an open barrel for more than three months during the hottest 
period of the year and.it still remained satisfactory for use. Certain 
changes, however, take place. With age the emulsion changes 
from a creamy yellow to a bluish color beneath the surface and an 
offensive sulphurous odor is given off. One lot separated and spoiled 
after remaining in an open barrel a year, and efforts to reemulsifv 
it by adding water and more kaolin were not successful. 
BRICK CLAY AS AN EMULSIFIER 
Brick clay was also tested and found to make a perfect emulsion, 
but because of the presence of more or less sand in the clay it probably 
would not be a satisfactory emulsifier for spraying emulsions. 
In addition to the above-mentioned colloidal clays, hydrated 
lime and commercial Bordeaux pastes and powders were usea, tested 
in the laboratory only, and found to be reasonably satisfactory but 
not nearly as good as kaolin or fuller’s earth. 
KAOLIN LIME-SULPHUR OIL EMULSION 
After several unsuccessful attempts, kaolin also proved to be a 
satisfactory emulsifier to convert lime-sulphur solution and oil into 
an emulsion. The failures were due to the allowance of insufficient 
time for the kaolin to become completely dispersed by the lime- 
sulphur solution. It was thought advisable to emulsify the regular 
quantities of materials usually recommended for 150 gallons of 
standard dilution. They are as follow^: 
Mineral lubricating oil_gallons. _ 1 
Lime-sulphur solution_do— 3 
Kaolin_pounds. . 2 
