Collophanite column type reverse floating collecting agent

The invention relates to a collophanite column type reverse floating collecting agent. The processes comprises steps of 1) using mixed aliphatic acid with 0.3-1 parts of saturated aliphatic acid and 0.7-0 parts of unsaturated fatty acid as raw materials, wherein control temperature is 30-50 DEG C, and using nitrogen to bring in 0.5-1.5 parts of SO2 and 0.5-1.5 parts of C12 from the bottom of a reaction device in a stirring condition, wherein reaction time is 3-4 hours, so as to obtain required raw materials; 2) adding sodium hydroxide or potassium hydroxide potassium hydroxide into the obtained raw materials for reaction for 1-2 hours at a temperature of 70-80 DEG C so as to obtain aliphatic acid sodium salt or sylvite; 3) adding a compound, methy isobutyl methanol, which accounts for 5-20% by mass of dry base substance of the sodium fatty acid salt or the potassium fatty acid salt so as to obtain the collophanite column type reverse floating collecting agent; and 4) mixing the obtained collophanite column type reverse floating collecting agent with water in the proportion of 1:10-200. The collecting agent is advantaged by more than 30% reduction on use; high de-magging efficiency; high recycling rate of concentrate; high concentration ration of flotation; low cost of flotation reagents; and capability of obtaining qualified phosphate concentrate for middle-low grade carbonate type collophanite wherein selected raw ore accounts 15-18%.