Refractory article, coating composition for preventing redox reaction, and method of manufacturing a refractory article

A method of fabricating a mixing vessel, the method comprising:

• applying a slurry coating layer on at least a portion of an inner wall surface of a vessel body of the mixing vessel, the inner wall surface comprising platinum or a platinum alloy, wherein the slurry coating layer is only applied to portions of the inner wall surface above an upper interface of a glass melt with the inner wall surface, the slurry coating layer comprising a first refractory material, a second refractory material, and a third refractory material, the first refractory material comprising on an oxide basis:
• SiO2 in an amount of 60 wt % to 70 wt %;
• Al2O3 in an amount of 20 wt % to 30 wt %;
• B2O3 in an amount of 3 wt % to 6 wt %;
• and
• CaO in an amount of 2.4 wt % to 4.8 wt %, the second refractory material containing SiO2 as a main component, and the third refractory material containing alumina as a main component;
• and
• heat treating the slurry coating layer, thereby forming the refractory article, wherein the refractory article comprises a coating layer comprising whiskers distributed in a silica matrix, and the whiskers comprise a mullite crystalline phase;
• wherein:
• the mixing vessel comprises a stirrer comprising a shaft, one or more impellers attached to the shaft, and a catcher plate provide at the shaft;
• and
• the method further comprises applying the slurry coating layer to a lower surface of the catcher plate.