Abstract: With application of a new self-developed collector QAS224，the reverse flotation de-silicatation tests on a bauxite in Henan with Al₂O₃ grade of 64%，Al-Si ratio of about 6.1 were made through a process of a roughing- two cleanings-two scavenging.The results showed that under grinding fineness of -0.074 mm 81.24% and pH 11，a concentrate with Al₂O₃ grade of 67.79%，Al₂O₃ recovery of 81.72% and Al-Si ratio of 9.67 can be obtained.Hence，QAS224 was an effective collector in reverse flotation de-silicatation of bauxite.  

Key words: New-type QAS224 collector, Bauxite, Reverse flotation de-silicatation