Mixed metal hydroxides for thickening water or hydrophylic fluids
AssigneeThe Dow Chemical Company
InventorsJohn L. Burba, III, Greene W. Strother
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Abstract
Novel monodispersed crystalline mixed metal layered hydroxide compounds of the general formula are prepared: Li.sub.m D.sub.d T(OH).sub.(m+2d+3+na) A.sub.a.sup.n, where m is an amount from zero to 1; D is a divalent metal; d is the amount of D ions of from zero to 4; T is a trivalent metal; A represents anions or negative-valence radicals of valence n; na is from zero to -3; (m+d) is greater than zero; and (m+2d+3+na) is equal to or greater than 3. The D metal is preferably Mg and the T metal is preferably Al. These compounds are useful as gelling agents which impart beneficial thixotropic properties to various fluids, such as drilling fluids, especially when employed along with fluid loss agents.
Claims44
Monodispersed crystalline monolayer mixed metal hydroxide compounds conforming essentially to empirical formula
- Li.sub.m D.sub.d T(OH).sub.(m+2d+3+na) A.sub.a.sup.n, where
- D represents divalent metal ions,
- T represents trivalent metal ions,
- A represents monovalent or polyvalent anions or negative-valence radicals other than OH.sup.- ions,
- m is from about zero to about 1, representing the amount of Li ion,
- d is from about zero to about 4,
- (m+d) is greater than zero,
- na is from about zero to about -3,
- a is an amount of A ions of valence n,
- and where (m+2+3+na) is equal to or greater than 3,
- said compounds being characterized as being substantially monolayer unit cell crystals having a thickness in the range of about 8 to about 16 angstroms.
A gelled liquid agent for thickening process fluids, characterized by its thixotropicity and resistance to fluid loss, said gelled liquid agent comprising,
- a major proportion of a liquid which is compatible or miscible with said process fluid, and
- a minor proportion of monodispersed crystalline monolayer mixed metal hydroxide gellant which conforms substantially to the empirical formula
- Li.sub.m D.sub.d T(OH).sub.(m+2d+3+na) A.sub.a.sup.n, where
- m is the number of Li ions in the formula,
- D represents divalent metals and d is the number of D ions in the formula,
- T represents trivalent metal ions,
- A represents monovalent or polyvalent anions or negative-valence radicals other than OH.sup.- ions, and a represents the number of A ions in the formula, with n representing a valence of 1 or more,
- where m is from about zero to about 1,
- d is from about zero to about 4,
- (m+d) is greater than zero,
- na is from zero to -3,
- where (m+2d+3+na) is equal to or greater than 3, and
- where said mixed metal hydroxides are characterized as being substantially monolayer unit cell crystals having a thickness in the range of about 8 to about 16 angstroms.
The gelled liquid agent of claim 30 wherein the value of a in the formula is in the range of about 0.1 to about 1.0.
A method for producing dispersed flocs of monolayer metal hydroxide compounds conforming essentially to the formula
- Li.sub.m D.sub.d T.sub.t (OH).sub.(m+2d+3+na) A.sub.a.sup.n, where
- m represents a quantity of from zero to 1,
- D represents divalent metal
- d represents a quantity of from zero to 4,
- T represents trivalent metal cations,
- t represents a quantity of from zero to 1,
- A represents monovalent or polyvalent anions or negative-valence radicals other than OH.sup.- ions,
- a is the amount of A ions of valence n,
- na is a quantity of from zero to -3,
- (d+t) is greater than zero,
- (m+2d+3t+na) is equal to, or greater than equal to, 3t or 2d, whichever is greater,
- said compounds being formed by merging, in a reaction zone, a measured or metered quantity of a metal cation-containing feed solution with a predetermined quantity of a hydroxyl ion-containing feed solution in a manner whereby rapid, intimate mixing is achieved in the reaction zone, while substantially avoiding shearing agitation which would break up the flocs which form during said mixing as a result of the reaction which occurs therein,
- removing the so-formed reaction mixture from the reaction zone ahead of subsequent measured or metered quantities of the feed solutions, thereby substantially avoiding the mixing, in the reaction zone, of the subsequent quantities of feed solutions with prior quantities of feed solutions,
- said method being carried out under substantially steady-state carried, using substantially constant conditions, in the reaction zone, of temperature, pH, and ratio of reactants,
- whereby the monolayer metal hydroxide compounds produced are characterized as being substantially monolayer unit cell crystals having a thickness in the range of about 8 to about 16 angstroms.
A composition for use as a drilling fluid component, said composition comprising a liquid having dispersed therein at least one monodispersed monolayer crystalline metal hydroxide conforming essentially to the empirical formula
- Li.sub.m D.sub.d T(OH).sub.(m+2d+3+na) A.sub.a.sup.n, where
- D represents divalent metal ions,
- T represents trivalent metal ions,
- A represents monovalent or polyvalent anions or negative-valence radicals other than OH.sup.- ions,
- m is from about zero to about 1, representing the amount of Li ion,
- d is from about zero to about 4,
- (m+d) is greater than zero, and
- na is from about zero to about -3;
- and
- a is an amount of A ions of valence n,
- where (m+2d+3+na) is equal to or greater than 3 wherein said drilling fluid also contains at least one fluid loss control agent.
Dependencies are inferred from the claim text.