Vermiculite composition with improved chemical exfoliation

Claim 2

A vermiculite composition comprising a vermiculite ore concentrate material having at least 85% of at least one vermiculite mineral specie or mixture thereof having a specific density in the range of from 2.3 g/cm 3 to 2.7 g/cm 3 and at least 30 meq/100 gm of the vermiculite mineral specie of intercalated cations selected from the group consisting of lithium, (C 2 -C 6 alkyl) ammonium, allylammonium, or ammonium C 3 -C 6 alkyl carboxylic acid.

Claim 3

The composition of claim 1 wherein the intercalated cation is selected from lithium.

Claim 4

The composition of claim 1 wherein the intercalated cation is present in from about 50 to 150 meq./100 gm of vermiculite.

Claim 5

A process for preparing a vermiculite dispersion comprising a) separating vermiculite mineral material having a specific density within the range of from 2.3 g/cm 3 to 2.7 g/cm 3 from previously formed vermiculite ore concentrate; b) treating said separated vermiculite mineral material with a cation exchange salt having a cation selected from the group consisting of lithium, (C 2 -C 6 alkyl) ammonium, allyl ammonium, or ammonium (C 3 -C 6 alkyl) carboxylic acid to cause said cation to be intercalated in the vermiculite mineral material; c) immersing the treated vermiculite mineral material in water substantially free of electrolyte; d) permitting the immersed vermiculite mineral material to swell in a direction normal to a main cleavage plane thereof to form swollen vermiculite minerals material; and e) subjecting the resultant swollen vermiculite mineral material while immersed in water to a shearing force to delaminate the vermiculite mineral material; and f) forming an aqueous substantially uniform suspension of delaminated vermiculite platelets.

Claim 6

A process for preparing a vermiculite dispersion comprising a) separating vermiculite mineral material having a specific density within the range of from 2.3 g/cm 3 to 2.7 g/cm 3 from previously formed vermiculite ore concentrate; b) treating said separated vermiculite mineral material with a cation exchange salt having a cation selected from the group consisting of lithium, (C 2 -C 6 alkyl) ammonium, allyl ammonium, or ammonium (C 3 -C 6 alkyl) carboxylic acid to cause said cation to be intercalated in the vermiculite mineral material; c) immersing the treated vermiculite mineral material in water substantially free of electrolyte; d) permitting the immersed vermiculite mineral material to swell in a direction normal to a main cleavage plane thereof to form swollen vermiculite minerals material; and e) subjecting the resultant swollen vermiculite mineral material while immersed in water to a shearing force to delaminate the vermiculite mineral material; and f) forming an aqueous substantially uniform suspension of delaminated vermiculite platelets.

Claim 7

The process of claim 4 wherein the cation exchange salt is a salt of citric acid.

Claim 8

The process of claim 4 wherein the vermiculite material is contacted with an aqueous treatment solution containing both citric acid or a soluble salt of citric acid and a soluble non-citrate cation exchange salt of the selected cation.

Claim 9

The process of claim 4 wherein the cation is selected from lithium or n-butyl ammonium.

Claim 10

The process of claim 5 wherein the cation is selected from lithium or n-butyl ammonium.

Claim 11

The process of claim 6 wherein the cation is selected from lithium or n-butyl ammonium.

Claim 12

The process of claim 4 wherein the suspension of step (f) further contains an anionic chelating agent in effective amount to enhance dispersion of the vermiculite platelets.

Claim 13

The process of claim 4 wherein the separated vermiculite material is composed of at least 90% vermiculite mineral having a specific density of from 2.3 g/cm 3 to 2.6 g/cm 3 .

Claim 14

The process of claim 4 wherein the separated vermiculite mineral material is treated with cation exchange salt to cause the vermiculite to have at least 30 meq./100 gm of cation intercalated therein.

Claim 15

The process of claim 7 wherein the separated vermiculite mineral material is treated with cation exchange salt to cause the vermiculite to have at least 30 meq./100 gm of cation intercalated therein.

Claim 16

A vermiculite product comprising a substantially uniform colloidal dispersion of delaminated vermiculite platelets formed according to the process of claim 4.

Claim 17

A vermiculite product comprising a substantially uniform colloidal dispersion of delaminated vermiculite platelets formed according to the process of claim 5.

Claim 18

A vermiculite product comprising a substantially uniform colloidal dispersion of delaminated vermiculite platelets formed according to the process of claim 6.

Claim 19

A vermiculite product comprising a substantially uniform colloidal dispersion of delaminated vermiculite platelets formed according to the process of claim 7.

Claim 20

A vermiculite product comprising a substantially uniform colloidal dispersion of delaminated vermiculite platelets formed according to the process of claim 8.

Claim 21

A vermiculite product comprising a substantially uniform colloidal dispersion of delaminated vermiculite platelets formed according to the process of claim 9.

Claim 22

A vermiculite product comprising a substantially uniform colloidal dispersion of delaminated vermiculite platelets formed according to the process of claim 10.

Claim 23

A process for preparing a vermiculite dispersion containing a) separating vermiculite mineral material having a specific density within the range of from 2.3 g/cm 3 to 2.7 g/cm 3 from previously formed vermiculite ore concentrate; b) treating said separated vermiculite mineral material with an aqueous composition of a salt having allyl ammonium cations to cause said cations to be intercalated in the vermiculite in at least 30 meq/100 gm of said vermiculite mineral material; c) subjecting the aqueous composition containing the treated vermiculite mineral material to a shearing force to delaminate the vermiculite mineral material; and d) forming an aqueous, substantially uniform suspension of delaminated vermiculite platelets having an aspect ratio of at least 500:1.

Claim 24

A process for preparing a vermiculite dispersion containing a) separating vermiculite mineral material having a specific density within the range of from 2.3 g/cm 3 to 2.7 g/cm 3 from previously formed vermiculite ore concentrate; b) treating said separated vermiculite mineral material with an aqueous composition of a salt having allyl ammonium cations to cause said cations to be intercalated in the vermiculite in at least 30 meq/100 gm of said vermiculite mineral material; c) subjecting the aqueous composition containing the treated vermiculite mineral material to a shearing force to delaminate the vermiculite mineral material; and d) forming an aqueous, substantially uniform suspension of delaminated vermiculite platelets having an aspect ratio of at least 500:1.