Modified amine-aldehyde resins and uses thereof in separation processes

A method for purifying bitumen, comprising:

• a. providing an aqueous slurry comprising bitumen and one or more soluble or insoluble impurities;
• b. contacting the aqueous slurry with an amine-aldehyde resin comprising a silane coupling agent, and
• c. during or after the treating step, separating the bitumen from the aqueous slurry by froth flotation;
• wherein the froth comprises a lower concentration of at least one or more soluble or insoluble impurities relative to the aqueous slurry;
• and
• wherein the amine-aldehyde resin comprises a urea-formaldehyde resin prepared by:
• mixing formaldehyde, urea, triethanolamine and optionally ammonia reactants at an alkaline pH, heating the mixture to an elevated temperature for a time sufficient to obtain complete metholylation of the urea, the reactants being present in an amount of about 1.50 to 4.0 moles of formaldehyde, about 0.001 to 0.1 mole of triethanolamine, and about 0.0 to 0.5 mole ammonia, per mole of urea;
• and
• adding acid to lower the pH to within the range of about 4.9 to about 5.2 and adding urea until the molar formaldehyde to urea ratio is within the range of about 1, 5:1 to about 2.5:1 and reacting for a time sufficient to reduce free formaldehyde to less than 2%.

A method of beneficiation of an ore, comprising

• a. providing an ore comprising a value mineral and one or more impurities;
• b. treating an aqueous slurry of the ore with an amine-aldehyde resin comprising a silane coupling agent, and
• c. during or after the treating step, separating the value material from the aqueous slurry by froth flotation;
• wherein the amine-aldehyde resin comprises a urea-formaldehyde resin prepared by:
• mixing formaldehyde, urea, triethanolamine and optionally ammonia reactants at an alkaline pH, heating the mixture to an elevated temperature for a time sufficient to obtain complete metholylation of the urea, the reactants being present in an amount of about 1.50 to 4.0 moles of formaldehyde, about 0.001 to 0.1 mole of triethanolamine, and about 0.0 to 0.5 mole ammonia, per mole of urea;
• and
• adding acid to lower the pH to within the range of about 4.9 to about 5.2 and adding urea until the molar formaldehyde to urea ratio is within the range of about 1.5:1 to about 2.5:1 and reacting for a time sufficient to reduce free formaldehyde to less than 2%.