Methods of making honeycomb bodies having inorganic filtration deposits

A method for applying a surface treatment to a honeycomb body comprising porous walls, comprising:

• mixing an atomizing gas with a liquid-particulate-binder-adhesion promoter stream, the liquid-particulate-binder-adhesion promoter stream comprising particles of an inorganic material, an aqueous vehicle, an alkyltrialkoxysilane binder, and an alkoxysilane adhesion promoter;
• directing the liquid-particulate-binder-adhesion promoter stream and an atomizing gas through an atomizing nozzle, thereby aerosolizing the particles into liquid-particulate-binder-adhesion promoter droplets comprising the aqueous vehicle, the binder, the adhesion promoter, and the particles;
• conveying the droplets toward the honeycomb body by a gaseous carrier stream through a duct having an outlet end proximate the honeycomb body, the gaseous carrier stream comprising a carrier gas and the atomizing gas, the carrier gas delivered to a chamber of the duct in an annular flow surrounding the nozzle in a co-flow around the droplets at the end of the nozzle;
• evaporating substantially all the aqueous vehicle from the droplets to form agglomerates comprising the particles, the binder, and the adhesion promoter;
• depositing the agglomerates onto the honeycomb body, the deposited agglomerates disposed on, or in, or both on and in, the porous walls;
• and
• wherein during the depositing the duct is in sealed fluid communication with a deposition zone housing the honeycomb body.

A method for applying a surface treatment to a honeycomb body comprising porous walls, the method comprising:

• mixing particles of an inorganic material with an aqueous vehicle, a binder having the formula (C2H4O)R1OR2Si(OR3)3, where R1 and R2 independently comprise a C1-C12 substituted or unsubstituted alkyl, and R3 comprises a C1-C5 unsubstituted alkyl, and an adhesion promoter comprising an alkoxysilane to form a liquid-particulate-binder-adhesion promoter stream;
• mixing the liquid-particulate-binder-adhesion promoter stream with an atomizing gas;
• directing the liquid-particulate-binder-adhesion promoter stream and an atomizing gas into an atomizing nozzle to aerosolize the particles into liquid-particulate-binder-adhesion promoter droplets comprising the aqueous vehicle, the binder, the adhesion promoter, and the particles;
• conveying the droplets toward the honeycomb body by a gaseous carrier stream through a duct having an outlet end proximate the honeycomb body, the gaseous carrier stream comprising a carrier gas and the atomizing gas;
• evaporating substantially all the aqueous vehicle from the droplets to form agglomerates comprising the particles, the binder, and the adhesion promoter;
• and
• depositing the agglomerates onto the honeycomb body, the deposited agglomerates disposed on, or in, or both on and in, the porous walls.