Claims
- 1. A kaolin clay slurry formed by a process which comprises the sequential steps of:
- A. obtaining a homogeneous mixture by mixing, in the absence of a dispersant, kaolin clay and a collector to condition the impurities, wherein water is present in an amount sufficient to yield a mixture having a solids content of at least 65% by weight; and
- B. deflocculating the kaolin clay mixture at a pH of at least 4.0 with a dispersant in an amount sufficient to yield a kaolin clay slurry which is suitable for subsequent processing to remove colored titaniferous impurities.
- 2. A kaolin clay slurry as defined by claim 1 wherein the collector is a fatty acid compound having the general formula: ##STR3## in which R is an alkyl, aryl or alkylaryl group having 1-26 carbon atoms, and M is hydrogen, an alkali metal or an alkaline earth metal.
- 3. A kaolin clay slurry as defined by claim 2 wherein R is methyl, ethyl, butyl, octyl, lauryl, 2-ethylhexyl, oleyl, eicosyl, phenyl, tolyl, naphthyl or hexylphenyl.
- 4. A kaolin clay slurry as defined by claim 2 wherein M is hydrogen, lithium, sodium, potassium, magnesium, calcium or barium.
- 5. A kaolin clay slurry as defined by claim 2 wherein the fatty acid compound is a tall oil.
- 6. A kaolin clay slurry as defined by claim 1 wherein the collector is a hydroxamate compound having the general formula: ##STR4## in which R' is an alkyl, aryl or alkylaryl group having 4-28 carbon atoms, and M' is hydrogen, an alkali metal or an alkaline earth metal.
- 7. A kaolin clay slurry as defined by claim 6 wherein R' is butyl, octyl, lauryl, 2-ethylhexyl, oleyl, eicosyl, phenyl, tolyl, naphthyl or hexylphenyl.
- 8. A kaolin clay slurry as defined by claim 6 wherein M' is hydrogen, lithium, sodium, potassium, magnesium, calcium or barium.
- 9. A kaolin clay slurry as defined by claim 6 wherein the hydroxamate compound is an alkyl hydroxamate.
- 10. A kaolin clay slurry as defined by claim 1 wherein the dispersant is sodium silicate.
- 11. A kaolin clay slurry as defined by claim 1 wherein the dispersant is a polyacrylate.
- 12. A kaolin clay slurry as defined by claim 1 wherein the dispersant is sodium hexametaphosphate.
- 13. A kaolin clay slurry as defined by claim 1 wherein a pH modifier is added in step (B).
- 14. A kaolin clay slurry as defined by claim 13 wherein the pH modifier is soda ash, sodium hydroxide, ammonium hydroxide, potassium hydroxide, lithium hydroxides or mixtures thereof.
- 15. A kaolin clay slurry as defined by claim 1 wherein a frothing agent is added in step (B).
Parent Case Info
This application is a continuation-in-part of U.S. patent application Ser. No. 08/509,506, filed Jul. 28, 1995, now U.S. Pat. No. 5,685,899.
US Referenced Citations (9)
Continuation in Parts (1)
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Number |
Date |
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Parent |
509506 |
Jul 1995 |
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