Diamine flotation of quartz

Adsorption of N-Tallow 1,3-Propanediamine–Dioleate Collector on Albite and Quartz Minerals, and Selective Flotation of Albite from Greek Stefania Feldspar Ore

“…The solubility of molecular species decreases about 1 3 for each additional CH 2 group in the alkyl chain. Thus, a pK sol value of 8.39 was considered as the solubility for C 12 -diaminopropane was reported to be 3.6 × 10 −7 kmol/m 3 (23). It is presumed that the solution chemistry of the diamine-dioleate molecule will be similar to the hydrolysis of oleic acid and the ionization of amines in aqueous solutions.…”

“…However, at pH 4 the charge reversal for albite occurs at a collector concentration of 5 × 10 equilibrium constants for C 16 -diaminopropane (23) and sodium oleate (24) were used in the calculation of the respective ionic and molecular species concentrations of the collector at various pH values. The average alkyl chain of the diamine part of the molecule is about C 16 , and the pK a1 and pK a2 values of 6.8 and 9.3, respectively, for C 12 -diaminopropane were used since the pK a values reportedly change very little with chain length (23). The solubility of molecular species decreases about 1 3 for each additional CH 2 group in the alkyl chain.…”

Mechanisms of Amine–Quartz Interaction in the Absence and Presence of Alcohols Studied by Spectroscopic Methods

“…The presence of molecular amine at higher concentrations of C 16 amine acetate might be related to its low solubility in comparison to dodecyl amine acetate. The solubility of dodecyl amine was 2 × 10 −5 M and the solubility decreases about one-third for each additional hydrocarbon group added to the alkyl chain (34).…”

Role of Water Structure-Making/Breaking Ions in the Cationic Flotation of Kaolinite: Implications for Iron Ore Processing

“…Ether monoamine and ether diamine are both used as the collectors of silicate gangue minerals in the iron ore industry. It is known that diamines are stronger collectors for quartz, in comparison to monoamines with comparable chain length [7,[17][18][19][20][21], because of the more acidic pKa values of diamines in comparison to monoamines and the doubly charged amine species of the diamines which promote stronger flotation of quartz [21]. However, for the flotation of kaolinite, whose flotation mechanism is different from that of quartz, ether diamine does not induce any flotation recovery of kaolinite particles at all.…”