This disclosure relates a method of reducing water production in a wellbore, which may include introducing an alkaline nanosilica dispersion to the wellbore such that it contacts a water producing zone of the wellbore, introducing a sodium bicarbonate activator to the wellbore such that it contacts the alkaline nanosilica dispersion in the water producing zone, and forming a gelled solid from the water shutoff material in the water producing zone, thereby reducing water production in the wellbore.

This disclosure relates a method of reducing water production in a wellbore, which may include introducing an alkaline nanosilica dispersion to the wellbore such that it contacts a water producing zone of the wellbore, introducing a sodium bicarbonate activator to the wellbore such that it contacts the alkaline nanosilica dispersion in the water producing zone, and forming a gelled solid from the water shutoff material in the water producing zone, thereby reducing water production in the wellbore.

Disclosed are cement compositions for applying to honeycomb bodies as a plugging cement composition, segment cement, or even as an after-applied artificial skin or coating. The cement compositions generally comprise an inorganic powder batch mixture; an organic binder; a liquid vehicle; and a gelled inorganic binder. Also disclosed are honeycomb bodies having the disclosed cement compositions applied thereto, and methods for making same.

Disclosed are cement compositions for applying to honeycomb bodies as a plugging cement composition, segment cement, or even as an after-applied artificial skin or coating. The cement compositions generally comprise an inorganic powder batch mixture; an organic binder; a liquid vehicle; and a gelled inorganic binder. Also disclosed are honeycomb bodies having the disclosed cement compositions applied thereto, and methods for making same.

Disclosed are cement compositions for applying to honeycomb bodies as a plugging cement composition, segment cement, or even as an after-applied artificial skin or coating. The cement compositions generally comprise an inorganic powder batch mixture; an organic binder; a liquid vehicle; and a gelled inorganic binder. Also disclosed are honeycomb bodies having the disclosed cement compositions applied thereto, and methods for making same.

Cementitious compositions comprising a hydraulic cementitious material, a compound selected from the group consisting of a polyhydroxy aromatic compound, a polycarboxylic acid-containing compound or a salt thereof, ascorbic acid or a salt thereof, or a combination thereof, and a particulate material or a water soluble silicate-containing material that interacts with the compound are described herein. The polyhydroxy aromatic compound can be a water soluble compound having from two to thirty hydroxyl groups. The particulate material can exhibit a particle size distribution, wherein at least about 90% by weight of the particles have a diameter of less than 2 mm. Suitable particulate materials include nanoparticles and microparticles. The cementitious compositions can be used to form building materials. The cementitious compositions are especially suited for inhibiting corrosion of reinforcing steel bars embedded in concrete mixtures. Methods of making and using the cementitious composition are also disclosed.

Cementitious compositions comprising a hydraulic cementitious material, a compound selected from the group consisting of a polyhydroxy aromatic compound, a polycarboxylic acid-containing compound or a salt thereof, ascorbic acid or a salt thereof, or a combination thereof, and a particulate material or a water soluble silicate-containing material that interacts with the compound are described herein. The polyhydroxy aromatic compound can be a water soluble compound having from two to thirty hydroxyl groups. The particulate material can exhibit a particle size distribution, wherein at least about 90% by weight of the particles have a diameter of less than 2 mm. Suitable particulate materials include nanoparticles and microparticles. The cementitious compositions can be used to form building materials. The cementitious compositions are especially suited for inhibiting corrosion of reinforcing steel bars embedded in concrete mixtures. Methods of making and using the cementitious composition are also disclosed.

A catalyst fibrous structure having a catalyst metal carried on a fibrous structure, wherein (a) a Log differential micropore volume distribution curve thereof obtained by measurement using a mercury intrusion technique has a peak having a maximum micropore diameter in the range of from 0.1 μm to 100 μm; (b) a Log differential micropore volume at the peak is 0.5 mL/g or more; and (c) an amount of a catalyst metal compound and a binder carried per unit volume is 0.05 g/mL or more. A production method for producing a catalyst fibrous structure having: (1) mixing a catalyst metal compound or a catalyst precursor, and an inorganic binder and a solvent; (2) grinding the mixture to obtain a coating material of the catalyst metal compound or the catalyst precursor having a median particle diameter of 2 μm or less and a viscosity of from 10 mPa.Math.s to 200 mPa.Math.s; (3) impregnating a fibrous structure with the coating material to fill up voids of the fibrous structure with the coating material of the catalyst metal compound or the catalyst precursor; (4) heating and drying the fibrous structure, directly as it is, at a temperature not lower than the boiling point of the solvent; and (5) heating and calcination the dried fibrous structure at a temperature not lower than the dehydration temperature of the inorganic binder to obtain a catalyst fibrous structure.

A catalyst fibrous structure having a catalyst metal carried on a fibrous structure, wherein (a) a Log differential micropore volume distribution curve thereof obtained by measurement using a mercury intrusion technique has a peak having a maximum micropore diameter in the range of from 0.1 μm to 100 μm; (b) a Log differential micropore volume at the peak is 0.5 mL/g or more; and (c) an amount of a catalyst metal compound and a binder carried per unit volume is 0.05 g/mL or more. A production method for producing a catalyst fibrous structure having: (1) mixing a catalyst metal compound or a catalyst precursor, and an inorganic binder and a solvent; (2) grinding the mixture to obtain a coating material of the catalyst metal compound or the catalyst precursor having a median particle diameter of 2 μm or less and a viscosity of from 10 mPa.Math.s to 200 mPa.Math.s; (3) impregnating a fibrous structure with the coating material to fill up voids of the fibrous structure with the coating material of the catalyst metal compound or the catalyst precursor; (4) heating and drying the fibrous structure, directly as it is, at a temperature not lower than the boiling point of the solvent; and (5) heating and calcination the dried fibrous structure at a temperature not lower than the dehydration temperature of the inorganic binder to obtain a catalyst fibrous structure.

A process for treating a tailings stream comprising water, solids, and optionally polyacrylamide. The process involves (a) contacting the tailings stream with a silicate source for a pre-determined period of time to form a mixture; b) after a pre-determined period of time of at least 5 minutes, contacting the mixture with an activator to initiate gel formation, wherein the gel entraps the solids within the gel; and c) allowing the gel to strengthen and solidify; wherein the gel formation is delayed compared with a non-delayed process.