Abstract: In order to effectively solve the problem that the traditional phosphate rock reverse flota⁃ tion to remove potassium feldspar cationic collector must be used in conjunction with the adjustment agent， in view of the problem of difficult flotation separation of a medium and low grade siliceous calcium phos⁃ phate rock in Hubei，the reverse flotation test of coarse-grained phosphate rock and fine-grained phos⁃ phate rock is carried out.The results show that when Z-1 is used as collector to remove potassium feldspar， the phosphate concentrate with P2O5 grade of 31.15%，Al2O3 content of 1.74% and P2O5 recovery of 82.21% can be obtained by reverse flotation of coarse-grained phosphate rock without using any acid and alkali.The phosphate concentrate with P2O5 grade of 30.82%，Al2O3 content of 1.80% and P2O5 recovery of 57.79% can be obtained by reverse flotation of fine-grained phosphate rock. The collector Z-1 has excel⁃ lent selective collecting ability for potassium feldspar，and the reagent cost is 7.9 yuan/t lower than that of the traditional reagent，which can provide reference for the efficient separation of similar refractory phos⁃ phate rock and the removal of potassium feldspar.

Key words: refractory collophanite, potassium feldspar, reagent selection, collector Z-1