US4510254A — Method of treating zeolite ores to remove discolo…

Claim 1

Independent Claim 206 words

A method of treating zeolite ores to remove therefrom discoloring impurities and improve the brightness characteristics thereof, said method comprising the steps of: (a) mixing a pulverized zeolite ore with a dispersant and water to disperse said zeolite and form an aqueous zeolite slurry; (b) degritting said aqueous zeolite slurry to remove grit having a particle size of 44 μm or more; (c) removing fines having a particle size of at least 50% less than 2 μm or less and containing discoloring impurities from said degritted zeolite slurry; (d) subjecting a mixture of the zeolite slurry after fines removal step (c) and a fine grinding media to rapid agitation to effect a fine milling of said zeolite to a particle size of at least 20% less than 2 μm and removing said grinding media from said fine milled zeolite slurry; (e) removing fines having a particle size of at least 40% less than 2 μm or less and containing discoloring impurities from the fine milled zeolite slurry; (f) subjecting said fine milled zeolite slurry after said fines removal step (e) to magnetic separation to remove magnetic discoloring impurities; (g) bleaching the resulting zeolite slurry; and (h) recovering the zeolite in dry form from the resulting slurry.

Claim 2

Independent Claim 206 words

A method of treating zeolite ores to remove therefrom discoloring impurities and improve the brightness characteristics thereof, said method comprising the steps of: (a) mixing a pulverized zeolite ore with a dispersant and water to disperse said zeolite and form an aqueous zeolite slurry; (b) degritting said aqueous zeolite slurry to remove grit having a particle size of 44 μm or more; (c) removing fines having a particle size of at least 50% less than 2 μm or less and containing discoloring impurities from said degritted zeolite slurry; (d) subjecting a mixture of the zeolite slurry after fines removal step (c) and a fine grinding media to rapid agitation to effect a fine milling of said zeolite to a particle size of at least 20% less than 2 μm and removing said grinding media from said fine milled zeolite slurry; (e) removing fines having a particle size of at least 40% less than 2 μm or less and containing discoloring impurities from the fine milled zeolite slurry; (f) subjecting said fine milled zeolite slurry after said fines removal step (e) to magnetic separation to remove magnetic discoloring impurities; (g) bleaching the resulting zeolite slurry; and (h) recovering the zeolite in dry form from the resulting slurry.

Claim 3

Dependent Claim 19 words

Method as claimed in claim 1 wherein said zeolite ore is chiefly clinoptilolite, chabazite, mordenite, erionite, phillipsite or analcine.

Claim 4

Dependent Claim 13 words

Method as claimed in claim 2 wherein said zeolite ore is chiefly clinoptilolite.

Claim 5

Dependent Claim 23 words

Method as claimed in claim 3 wherein said bleaching step (g) is carried out by adding an oxidative bleach to said zeolite slurry.

Claim 6

Dependent Claim 22 words

Method as claimed in claim 3 wherein said bleaching step is carried out by adding a reductive bleach to said zeolite slurry.

Claim 7

Dependent Claim 19 words

Method as claimed in claim 4 wherein said slurry after said oxidative bleach is subjected to a reductive bleach.

Claim 8

Dependent Claim 34 words

Method as claimed in claim 1 wherein said pulverized zeolite is washed with water and acid and separated from said water and acid prior to mixing with a dispersant and water in step (a).

Claim 9

Dependent Claim 23 words

Method as claimed in claim 7 wherein said zeolite is separated from said water and acid by filtration, washing with water and neutralization.

Claim 10

Dependent Claim 46 words

Method as claimed in claim 3 wherein the slurry following the removal of fines in step (e) is filtered and blunged with water and is mixed with a fine grinding media and subjected to rapid agitation to effect a second fine milling action on said zeolite.

Claim 11

Dependent Claim 28 words

Method as claimed in claim 9 wherein the zeolite slurry after magnetic separation step (f) is subjected to a second magnetic separation to remove additional magnetic discoloring impurities.

Claim 12

Dependent Claim 52 words

Method as claimed in claim 10 wherein the slurry following the second magnetic separation step is subjected to a fines removal step to remove fines having a particle size of at least 80% less than 2 μm and containing discoloring impurities from the zeolite slurry resulting from the second magnetic separation step.

Claim 13

Dependent Claim 74 words

Process as claimed in claim 11 wherein the zeolite slurry following the third fines removal step is mixed with a dispersant to disperse said zeolite and the resulting dispersed slurry is subjected to a third fine media milling wherein said zeolite slurry is mixed with a fine grinding media and subjected to rapid agitation to effect a fine milling of said zeolite to a particle size of at least 90% less than 2 microns.

Claim 14

Dependent Claim 43 words

Method as claimed in claim 9 wherein recovering step (h) comprises the steps of filtering the zeolite slurry after the bleaching step (g) and blunging the resulting filter cakes with water to form a zeolite slurry and spray drying the resulting zeolite slurry.

Claim 15

Dependent Claim 53 words

Method as claimed in claim 7 wherein said zeolite is separated from said water and acid by allowing the slurry of zeolite, water and acid to settle, decanting resulting supernatant liquid followed by filtering the remaining slurry, washing the resulting filter cakes with water and neutralizing the resulting zeolite slurries with a base.

Claim 16

Dependent Claim 16 words

Method as claimed in claim 9 wherein the dispersant used in step (a) is tetrasodium pyrophosphate.

Claim 17

Dependent Claim 35 words

Method as claimed in claim 12 wherein the dispersant used to disperse the slurry after the second magnetic separation step and the third fines removal step is a mixture of sodium polyacrylate and sodium carbonate.

Claim 18

Dependent Claim 78 words

Method as claimed in claim 7 wherein the slurry following magnetic separation is filtered and the resulting filter cakes blunged in water to form a zeolite slurry and the resulting slurry is mixed with a fine grinding media and subjected to rapid agitation to effect a fine milling action on said zeolite followed by removing said grinding media from said fine milled zeolite slurry and thereafter subjecting the resulting zeolite slurry to the bleaching step of claim 7.

Claim 19

Independent Claim 309 words

A method of treating zeolite ores to remove therefrom detrimental impurities and improve the brightness, said method comprising the steps of: (a) mixing a pulverized zeolite with a dispersant and water to disperse said zeolite and form an aqueous zeolite slurry; (b) degritting said aqueous zeolite slurry to remove grit having a particle size of 44 μm or more; (c) removing fines having a particle size of at least 50% less than 2 μm and containing discoloring impurities from said degritted zeolite slurry; (d) subjecting a mixture of the zeolite slurry after fines removal step (c) and a fine grinding media to rapid agitation to effect a fine-media milling of said zeolite to a particle size of at least 20% less than 2 μm; (e) removing fines having a particle size of at least 40% less than 2 μm and containing discoloring impurities from the fine-media milled zeolite slurry; (f) subjecting the fine-media milled zeolite slurry from step (e) above to another fine-media milling step by subjecting said slurry and a fine grinding media to rapid agitation to effect a fine-media milling of said zeolite to a particle size of at least 60% less than 2 μm; (g) removing fines having a particle size of at least 80% less than 2 μm and containing discoloring impurities from the fine-media milled zeolite slurry; (h) subjecting said fine-media milled zeolite slurry after fines removal step (g) to magnetic separation to remove magnetic discoloring impurities; (i) subjecting the zeolite slurry from step (h) above to a final fine-media milling step by subjecting said slurry and a fine grinding media to rapid agitation to effect a fine-media milling of said zeolite to a particle size of at least 90% less than 2 μm; (j) bleaching the resulting zeolite slurry, and (k) recovering the zeolite product in a dry form from the resulting slurry.

Claim 20

Independent Claim 309 words

A method of treating zeolite ores to remove therefrom detrimental impurities and improve the brightness, said method comprising the steps of: (a) mixing a pulverized zeolite with a dispersant and water to disperse said zeolite and form an aqueous zeolite slurry; (b) degritting said aqueous zeolite slurry to remove grit having a particle size of 44 μm or more; (c) removing fines having a particle size of at least 50% less than 2 μm and containing discoloring impurities from said degritted zeolite slurry; (d) subjecting a mixture of the zeolite slurry after fines removal step (c) and a fine grinding media to rapid agitation to effect a fine-media milling of said zeolite to a particle size of at least 20% less than 2 μm; (e) removing fines having a particle size of at least 40% less than 2 μm and containing discoloring impurities from the fine-media milled zeolite slurry; (f) subjecting the fine-media milled zeolite slurry from step (e) above to another fine-media milling step by subjecting said slurry and a fine grinding media to rapid agitation to effect a fine-media milling of said zeolite to a particle size of at least 60% less than 2 μm; (g) removing fines having a particle size of at least 80% less than 2 μm and containing discoloring impurities from the fine-media milled zeolite slurry; (h) subjecting said fine-media milled zeolite slurry after fines removal step (g) to magnetic separation to remove magnetic discoloring impurities; (i) subjecting the zeolite slurry from step (h) above to a final fine-media milling step by subjecting said slurry and a fine grinding media to rapid agitation to effect a fine-media milling of said zeolite to a particle size of at least 90% less than 2 μm; (j) bleaching the resulting zeolite slurry, and (k) recovering the zeolite product in a dry form from the resulting slurry.

Claim 21

Dependent Claim 12 words

Method as in claim 18 wherein said zeolite ore contains chiefly clinoptilolite.

Claim 22

Dependent Claim 15 words

Method as in claim 18 wherein said zeolite ore contains chiefly chabazite, erionite or analcime.

Claim 23

Dependent Claim 20 words

Method as in claim 18 wherein the dispersant used in step (a) is tetrasodium pyrophosphate, sodium silicate, or a polyacrylate.

Claim 24

Dependent Claim 33 words

Method as in claim 18 wherein said pulverized zeolite is washed with water and acid and separated from said water and acid prior to mixing with a dispersant and water in step (a).

Claim 25

Dependent Claim 16 words

Method as in claim 22 wherein said acid is hydrochloric acid, sulphuric acid or phosphoric acid.

Claim 26

Dependent Claim 24 words

Method as in claim 22 wherein the strenth of the acid solution may vary from 2 to 20 wt. percent of acid in water.

Claim 27

Dependent Claim 22 words

Method as in claim 22 wherein said zeolite is separated from said water and acid by filtration, washing with water and neutralization.

Claim 28

Dependent Claim 35 words

Method as in claim 22 wherein said zeolite is separated from said water and acid by allowing the slurry of zeolite, water and acid to settle, decanting resultant supernatant liquid prior to filtration and neutralization.

Claim 29

Dependent Claim 16 words

Method as in claim 1 wherein magnetic separation step (h) precedes the fines removal step (g).

Claim 30

Dependent Claim 27 words

Method as in claim 1 wherein the zeolite slurry after magnetic separation step (h) is subjected to a second magnetic separation to remove additional magnetic discoloring impurities.

Claim 31

Dependent Claim 21 words

Method as in claim 1 wherein said bleaching step (j) is carried out using an oxidative bleach or a reductive bleach.

Claim 32

Dependent Claim 21 words

Method as claimed in claim 29 wherein said bleach is ozone, sodium hypochlorite, potassium monopersulfate, sodium dithionite, thiourea dioxide or chlorine.

Claim 33

Dependent Claim 45 words

Method as in claim 18 wherein recovery step (k) comprises the steps of filtering the zeolite slurry after the bleaching step (j) and blunging the resulting filter cakes with water and a dispersant to form a zeolite slurry and spray drying the resulting zeolite slurry.

Claim 34

Dependent Claim 27 words

Method as in claim 31 wherein the dispersant used to disperse the slurry after the bleaching step (j) is a mixture of sodium polyacrylate and sodium carbonate.

Claim 35

Dependent Claim 38 words

Method as in claim 18 wherein recovery step (k) comprises the steps of filtering the zeolite slurry after the bleaching step (j) and drying the resultant filter cakes in a convection oven at not more than 105° C.

Claim 36

Dependent Claim 36 words

Method as in claim 18 wherein products with TAPPI brightnesses of 80 or greater and particle sizes from 20 to 89% -2 μm are recovered from any intermediate step beginning with the fines removal step (c).

Claim 37

Dependent Claim 35 words

Dry powder or slurry of finely-ground zeolite product, from which discoloring impurities have been removed, having a particle size of at least 89% less than 2 μm and a TAPPI brightness of at least 91.

Claim 38

Dependent Claim 35 words

Dry powder or slurry of finely-ground zeolite product, from which discoloring impurities have been removed, having a particle size of at least 89% less than 2 μm and a TAPPI brightness of at least 91.

Claim 39

Dependent Claim 13 words

Zeolite product as in claim 35 wherein the major zeolite constituent is clinoptilolite.

Claim 40

Dependent Claim 31 words

Dry powder of mixed zeolite product containing clinoptilolite, chabazite, erionite, thompsonite and offretite having a TAPPI brightness of at least 84 and a particle size of at least 70% -2 μm.

Claim 41

Dependent Claim 31 words

Dry powder of mixed zeolite product containing clinoptilolite, chabazite, erionite, thompsonite and offretite having a TAPPI brightness of at least 84 and a particle size of at least 70% -2 μm.

Claim 42

Dependent Claim 26 words

Dry powder zeolite product containing chiefly analcime and having a TAPPI brightness of at least 81 and a particle size of at least 90% -2 μm.

Claim 43

Dependent Claim 26 words

Dry powder zeolite product containing chiefly analcime and having a TAPPI brightness of at least 81 and a particle size of at least 90% -2 μm.

Claim 44

Dependent Claim 30 words

Finely ground zeolite ore from which discoloring impurities have been removed, having a particle size of at least 85% below 2 μm and a Tappi brightness of at least 90.

Claim 45

Dependent Claim 30 words

Finely ground zeolite ore from which discoloring impurities have been removed, having a particle size of at least 85% below 2 μm and a Tappi brightness of at least 90.

Claim 46

Dependent Claim 14 words

Finely ground zeolite ore as claimed in claim 19 wherein said zeolite is clinoptilolite.

Claim 47

Dependent Claim 30 words

Finely ground zeolite ore from which discoloring impurities have been removed, having a particle size of at least 30% below 2 μm and a TAPPI brightness of at least 83.

Claim 48

Dependent Claim 30 words

Finely ground zeolite ore from which discoloring impurities have been removed, having a particle size of at least 30% below 2 μm and a TAPPI brightness of at least 83.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	1988-04-08	1988-10-08	1989-04-09	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	1992-04-08	1992-10-08	1993-04-09	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	1996-04-08	1996-10-08	1997-04-09	$7700.00	Window Closed / Lapsed

Method of treating zeolite ores to remove discoloring impurities and improve its brightness and resulting finely ground zeolite

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