Frothers and modifiers

Flotation Reagents. Three types of chemical reagents are used during the froth flotation process collectors, frothers, and modifiers. 

Interaction of Solids With Flotation Reagents. For flotation to occur with the aid of reagents, such compounds must adsorb at the sohd—hquid interface unless the soHd to be floated is naturally hydrophobic. In this latter case only depression can be attempted by the use of additional ions or depressants that hinder bubble—particle adhesion. Frothers (typically long-chain alcohols) and/or modifying agents such as hydrocarbon oils can, however, be used to enhance the collection of naturally hydrophobic soflds such as M0S2, talc, or plastics. 

The newly developed modified alkyl hydroxamate reagents (from Cytec Industries) tested in this study include S-8704, S-8704D, S-8705, S-8706, S-8706D and S-8765, while the reference collectors used were Aero Promoter 6493 (also from Cytec) and tall oil. The crude clays were dispersed using sodium silicate while soda ash was used to adjust the pH. The frother used in the flotation tests was Aerofroth 70. 

Solution equilibria of flotation reagents. Solution equilibria of various surfactants such as collectors, frothers, modifiers, and flocculants, encompass acid-base equilibria, dissociation equilibria, association equilibria and polymer equilibria. Using these equilibria and also various parameters such as the pH of the solutions and the critical pH of the dissolution of insoluble flotagents, pA(a can be calculated and the state of active flotation reagent species in solution predicted. 

Reagents used in flotation, collectors, frothers, depressants, flocculants and inorganic modifiers can interact with each other in the flotation pulp and at the mineral-solution interface. The chemical equilibria involved in these interactions and the nature of the products will have a significant effect on their adsorption and the resultant flotation processes. 

Another category of reagents that is commonly used is known as frothers. Frothers are used to aid the formation of, and stabilize, the flotation froth. Generally, these reagents are organic heteropolar compounds. Pine oil, a widely used frother, contains aromatic alcohols. A wide range of synthetic frothers is also available. A conventional frother, MIBC (methylisobutyl carbinol), is used in potash flotation as a modifier to inhibit the formation of excessive amine froth [98]. 

Pine oil is the product that is distilled from pine stump or turpentine. Currently pine oil frothers (also called as 2 oil) are the modified products of turpentine. And the main functional component of pine oil frothers is terpenol. The general expression of terpenols is as follows ... 

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