Method of increasing the volume yield of exfoliated vermiculite

Abstract

A method is disclosed for increasing the volume yield of expanded vermiculite obtained by exfoliation of vermiculite ore particles. The method comprises the sequential steps of applying vegetable oil to the vermiculite ore particles and thermally exfoliating the vermiculite ore particles.

What is claimed is: 
     
       1. A method for increasing the volume yield of expanded vermiculite ore particles comprising the sequential steps of applying about 0.1% to about 1% by weight of a vegetable oil to said particles, based on the weight of said particles, at a temperature below that at which said ore particles undergo exfoliation and thermally exfoliating said ore particles in an expansion oven or expansion furnace. 
     
     
       2. A method of claim 1 wherein said vegetable oil is selected from the group consisting of soybean oil, castor oil, corn oil, sunflower oil, palm oil, cottonseed oil, peanut oil, olive oil, and fatty acids derived therefrom. 
     
     
       3. A method of claim 2 wherein said vegetable oil is soybean oil. 
     
     
       4. A method of claim 1 wherein said vegetable oil is sprayed onto said particles as said particles are tumbled in a rotating mixer. 
     
     
       5. A method of claim 1 wherein said particles are thermally exfoliated at a temperature in the range of about 1100° F. to 1900° F.