1. FLOTATION frothers

2. when  = 0 o, cos  = 1,  G flotation = 0, no flotation when  = 90 o, cos  = 0,  G = -  lg. full flotation Thus, flotation reagents can be classified into a)collector (decreases  G) b)frother (no or negligable change of  G) c)depressor (increases  G)  G flotation = G final - G initial = [  sg - (  sl +  lg )] A  sg =  sl +  lg cos 

3. Role of frother 1. Gas dispersion 2. Froth formation 3. Speeding up flotation 4. Improving selectivity of flotation (by interaction with collector)

4. frother structure with depth

5. frother structure H. Khoshdast, A. Sam, Flotation Frothers: Review of Their Classifications, Properties and Preparation, The Open Mineral Processing Journal, 2011, 4, 25-44 25, 1874-8414/11 2011

6. Other classifications of frothers H. Khoshdast, A. Sam, Flotation Frothers: Review of Their Classifications, Properties and Preparation, The Open Mineral Processing Journal, 2011, 4, 25-44 25, 1874-8414/11 2011

7. Neutral frothers applied in flotation Laskowski, 1988 (with some modifications)

8. Other classifications of frothers Class Property of aqueous solution Liquid-gas interactions at flotation concentrations Froth/foam Surface active Form colloidal solutions (fatty acids amine, sulfonates, sulfates) Stronly reduce water surface tension Form two (foam) and three (froths) phase systems Form true solutions (alcoholes) Change aqueous surface tension Form two (foam) and three (froths) phase systems Surface inactive Organic compounds forming true solutions (ethyl acetal, ethyl diacetone) Do not change aqueous surface tension Form only three phase system (froth) Inorganic electrolyties Increase surface tension of water Form weak foams and strong froths with hydrophobic particles Frothers classification (Lekki and Laskowski, 1974)

9. CMC – critical micellization concentration MIBC – metyloizobutylokarbinol Properties of frothers CMC Collector ions can be present in aqueous solution as free ions(a), premicellar species, (b) spherical micelles (c). Structures appear with increasing surfactant concentration in aqueous solution. Symbol o denotes ion appositively charged to surfactant ion

10. Properties of frothers CCC Data of Finch, J.A., Nesset, J., Acuna, C., 2008, Role of frother on bubble production and behaviour in flotation, Miner. Eng., 21, 949–957. CCC 95 denotes 95% in Sauter mean bubble size reduction compared to mean bubble size in water only. Plotted by Kowalczuk, Ind. Eng.Chem. Res., 2013 DF250

11. Atrafi et al., 2012, Mineral Eng., vol. 36-38, 138-144 in flotation important is dynamic surface tension

12. Relationship between flotation selectivity coefficient a and concentration of C x P y frother. ppm = g/dm. Note location of CCC. Kowalczuk, Ind. Eng.Chem. Res., 2013 CCC vs frother dose

13. HLB (Hydrophobic - Lipophilic balanse) HLB = 7 + hydrophilic groups – lipophylic groups Hydrophilic groups -O- 1.3 -OH (free) 1.9 -OH (sorbitan ring) 0.5 -SO 4 Na 38.7 -COOK 21.1 -COONa 19.1 -COOH 2.1 -SO 3 (H) (sulfonate) ~11 -tertiary amin 9.4 -ester (free) 2.4 Lipophilic groups -CH, –CH 2 –, CH 3 –, =CH– 0.475 -(CH 2 -CH 2 -CH 2 -O–) 0.15

14. HLB Application 1.5-3 Antifoaming reagents 3,5-6 Emulsification reagents 4-10 Frothers 7-9 Wetting reagent s 8-18 Emulsifikation reagents (oil in water) 13-15 Detergents 15-18 Solubilization reagents Application of surfactants depending on their HLB

15. CCC vs HLB Kowalczuk, Ind. Eng.Chem. Res., 2013

16. DFI and other Comparison of different frothers properties (DI, CCC, J w ) and ability to mechanical flotation  max. They are similar (Szyszka et al., 2008)

17. Quartz flotation in the presence of different frothers (Szyszka et al., 2008)

18. Drzymala, unpublished, 2013

19. a – selectivity coefficient of flotation  – useful component recovery in concentrate  r – non-useful components recovery in tailing Drzymala, unpublished, 2013

20. Frother familyTypenmHLBMW g/mol CCC 95, mmol/dm 3 Aliphatic alcohols C n 1-Propanol37.48603.933 1-Butanol47740.851 1-Pentanol56.53880.284 1-Hexanol66.051020.108 1-Heptanol75.581160.069 1-Octanol85.11300.062 2-Propanol37.48605.117 2-Butanol47741.041 2-Pentanol56.53880.341 2-Hexanol66.051020.108 2-Heptanol75.581160.078 2-Octanol85.11300.062 3-Pentanol56.53880.466 3-Hexanol66.051020.127 Propylene glycol ethers C n P m Propylene glycol methyl ether118.28900.489 Propylene glycol propyl ether317.331180.246 Propylene glycol butyl ether416.851320.159 Di(propylene glycol) methyl ether128.131480.176 Di(propylene glycol) propyl ether327.181760.091 Di(propylene glycol) butyl ether426.71900.063 Tri(propylene glycol) methyl ether137.982060.073 Tri(propylene glycol) propyl ether337.032340.047 Tri(propylene glycol) butyl ether436.552480.028 Polypropylene glycols P m Di propylene glycol29.251340.396 Tri propylene glycol39.1251920.172 Tetra propylene glycol492500.088 Poly propylene glycol 42578.6254250.014 Poly propylene glycol 7251287250.010 Poly propylene glycol 1000177.37510000.008 Commercial FX120-0166.051020.108 DowFroth 250 DF250147.832640.038 DowFroth 1021 DF102116.77.484200.014 FX160-0532.57.112070.072 FX160-0113.87.862510.048 F15078.6254250.014 F16042.56.632170.037 Frother properties Zhang, W., Nesset, J.E., Rao, R., Finch, J.A., 2012, Minerals, 2, 208–227.