Abstract: In order to study the effect of the number of carbon atoms in the hydrophobic carbon chain on the performance of the amine collector foaming ability， the aeration method was used to capture the foam volume of dodecylamine， tetradecylamine and hexadecylamine. The parameters such as foam half-life and foam size distribution were also measured. The results show that the order of the agents has biggest foam volume at pH=6.0 from high to low is tetradecylamine>hexadecylamine>dodecylamine. As the number of carbon atoms in the hydrophobic carbon chain increases， the interaction between the molecules increases， and the viscosity of the solution increases， so that the half-life of the foam is also greatly increased. The order of t1/2 from large to small is hexadecylamine>tetradecylamine>dodecylamine. When the foam Sauter diameter reach the minimum number， the dosage of agents from low to high is tetradecylamine

Key words: Carbon chain length, Foam properties, Amino group-containing collectors, Surface tension, Viscosity