The present invention concerns the use, for gas separation and/or gas drying, of at least one zeolite adsorbent material comprising at least one type A zeolite, said adsorbent having an external surface area greater than 20 m.sup.2.Math.g.sup.1, a non-zeolite phase (PNZ) content such that 0<PNZ30%, and an Si/Al atomic ratio of between 1.0 and 2.0. The invention also concerns a zeolite adsorbent material having an Si/Al ratio of between 1.0 and 2.0, a mesoporous volume of between 0.07 cm.sup.3.Math.g.sup.1 and 0.18 cm.sup.3.Math.g.sup.1, a (VmicroVmeso)/Vmicro ratio of between 3 and 1.0, non-inclusive, and a non-zeolite phase (PNZ) content such that 0<PNZ30%.

The present invention relates to novel microporous zirconium silicate compositions that are formulated to remove toxins, e.g. potassium ions, from the gastrointestinal tract at an elevated rate without causing undesirable side effects. The preferred formulations are designed avoid increase in pH of urine in patients and/or avoid potential entry of particles into the bloodstream of the patient. Also disclosed is a method for preparing high purity crystals of UZSi-9 exhibiting an enhanced level of potassium exchange capacity. These compositions are particularly useful in the therapeutic treatment of hyperkalemia.

The present invention relates to novel microporous zirconium silicate compositions that are formulated to remove toxins, e.g. potassium ions, from the gastrointestinal tract at an elevated rate without causing undesirable side effects. The preferred formulations are designed avoid increase in pH of urine in patients and/or avoid potential entry of particles into the bloodstream of the patient. Also disclosed is a method for preparing high purity crystals of UZSi-9 exhibiting an enhanced level of potassium exchange capacity. These compositions are particularly useful in the therapeutic treatment of hyperkalemia.

Methods for regenerating poisoned salt bath comprising providing a salt bath comprising at least one of KNO.sub.3 and NaNO.sub.3, providing an ion-exchangeable substrate comprising lithium cations, contacting at least a portion of the ion-exchangeable substrate with the salt bath, whereby lithium cations in the salt bath diffuse from the ion-exchangeable substrate and are dissolved in the salt bath, and selectively precipitating dissolved lithium cations from the salt bath using phosphate salt. The methods further include preventing or reducing the formation of surface defects in the ion-exchangeable substrate by preventing or reducing the formation of crystals on the surface of the ion-exchangeable substrate upon removal from the salt bath.

Methods for regenerating poisoned salt bath comprising providing a salt bath comprising at least one of KNO.sub.3 and NaNO.sub.3, providing an ion-exchangeable substrate comprising lithium cations, contacting at least a portion of the ion-exchangeable substrate with the salt bath, whereby lithium cations in the salt bath diffuse from the ion-exchangeable substrate and are dissolved in the salt bath, and selectively precipitating dissolved lithium cations from the salt bath using phosphate salt. The methods further include preventing or reducing the formation of surface defects in the ion-exchangeable substrate by preventing or reducing the formation of crystals on the surface of the ion-exchangeable substrate upon removal from the salt bath.

Provided is a composite material including a plurality of porous silicate particles having a glass phase structure, a first active metal adsorbed into the glass phase structure of the porous silicate particles, and a modified layer containing a second active metal formed on the surfaces of the porous silicate particles. The porous silicate particles have an average pore diameter of from 3 nm to 50 nm, and the first active metal includes at least one of sodium, potassium, calcium, and magnesium.

Provided is a composite material including a plurality of porous silicate particles having a glass phase structure, a first active metal adsorbed into the glass phase structure of the porous silicate particles, and a modified layer containing a second active metal formed on the surfaces of the porous silicate particles. The porous silicate particles have an average pore diameter of from 3 nm to 50 nm, and the first active metal includes at least one of sodium, potassium, calcium, and magnesium.

The present invention relates to an amorphous titanium stannate silicate with the general formula: M.sup.v+.sub.wTi.sub.xSi.sub.ySn.sub.zO.sub.2x+2y+2z+0.5vw, wherein M is proton, ammonium, a metal or a mixture of metals, wherein v is the valence of M being a positive integer, and wherein x, y, z and w are molar ratios: x is 1, y is from 0.01 to 99, z is from 0.01 to 99, and w is from 0.01 to 50. The described titanium stannate silicates are particularly useful in catalysis and adsorption.

The present invention relates to an amorphous titanium stannate silicate with the general formula: M.sup.v+.sub.wTi.sub.xSi.sub.ySn.sub.zO.sub.2x+2y+2z+0.5vw, wherein M is proton, ammonium, a metal or a mixture of metals, wherein v is the valence of M being a positive integer, and wherein x, y, z and w are molar ratios: x is 1, y is from 0.01 to 99, z is from 0.01 to 99, and w is from 0.01 to 50. The described titanium stannate silicates are particularly useful in catalysis and adsorption.

The present invention relates to zirconium silicate compositions having a lead content that is below 0.6 ppm and methods of manufacturing zirconium silicate at reactor volumes exceeding 200-L with a lead content below 1.1 ppm. The lead content of the zirconium silicate of this invention are within the levels that are considered acceptable for extended use given the dose requirements for zirconium silicate.