ENHANCED BULK HANDLING PROPERTIES OF POWDERS VIA DRY GRANULATION IN A CONTROLLED ATMOSPHERE

摘要

Powders such as pigmentary titanium dioxide (TiO2) often demonstrate poor bulk handling properties. It is very cohesive, often dusty, and many grades have loose bulk densities that are lower than desired by customers for their processes. The present invention relates to a process for manufacturing low-dusting, smoothly-discharging, easily dispersible, powders such as pigmentary titanium dioxide that resist compaction, aging, lumping, and/or caking. Particularly, the present invention relates to a process for treating powders such as pigmentary titanium dioxide with ammonia or a similarly basic substance prior to or during agglomeration to produce a powder with improved bulk handling properties. The present invention also relates to powders treated as such, including titanium dioxide.

主权项

1. A process for preparing powder with enhanced bulk handling property, comprising:
(A) contacting a powder with at least one gas in a controlled environment, wherein said at least one gas is capable of acting as a Lewis base in the aggregate to said powder; (B) optionally, tumbling said powder in said controlled environment simultaneously for at least a portion of the time during contacting of said at least one gas with said powder.