It depends on the reagent. Carbon, being naturally hydrophobic, will float easily, with a frother this could cause unwanted foam and floating of the carbon. Fuel oil based collectors will coat the carbon and this may inhibit gold collection.

A couple of publications from Research Gate that might be of pique:

The effect of flotation reagents on cyanidation, loading capacity and sorption kinetics of gold onto activated carbon

Mohammad Mehdi Salarirad • Ali Behnamfard

Department of Mining and Metallurgical Engineering, Amirkabir University of Technology (Tehran Polytechnic), Tehran, Iran

Hydrometallurgy (Impact Factor: 1.93). 12/2010; 105(1):47-53. DOI: 10.1016/j.hydromet.2010.07.009
Fouling effect of different flotation and dewatering reagents on activated carbon and sorption kinetics of gold.

I have worked on projects in the past where we were trying to regenerate activated carbon from a gold processing plant leaching a float tail. The short answer is yes; organics can and do foul up the carbon and significantly reduce its activity towards gold adsorption. This can lead to gold in solution losses in the tails, large carbon inventories in the circuit, and other issues.

The key findings from the work were that you should not overdose reagent in the float circuit upstream (this wastes reagent and also fouls carbon downstream). Plus you need to do a good carbon regen (we found with N2 and steam gave the best results) to reactivate the carbon fouled with organics.

In short, most probably residual float reagents in the float tails will cause fouling of the activated carbon. This is what I saw in the float plants where I worked. Regeneration requirements for a carbon fouled with float reagents will be more demanding (for example higher regen temp requirement). If not regenerated properly, gold in solution in the plant tails will possibly be higher (lost $$$). You also need to make sure VOC (volatile organic compound) concentrations in the kiln off gasses do not exceed environmental threshold limits that apply to your pla

Search for work done in the mid to late 80's by AMIRA in Australia, they did a mountain of work on all the different types of fouling agents for carbon, including all types of flotation collector, frothers, depressants, natural organics in the upper levels of open pits, calcium, other metals, even oils from the mine etc.