Activated coke for desulfurization & denitrification 

Activated coke is an excellent adsorbent, which can adsorb the SO2 and SO3 from industrial boilers’ flue gas emissions at the window temperature (120 ℃ ~ 180 ℃) without heating the flue gas; Meanwhile, activated coke is also a excellent catalyst, it can restore the NOx into N2 and H2O with the conditions of adding the reductant NH3. so the performance of activated coke is the core of flue gas purification effect.

 Iodine is used to indirectly measure the performance of the desulphurization, because test
 time of desulphurization needs around 1day.

Activated coke’s production process & facilities are similar as those for pellet activated carbons, but the specific conditions of the production process, raw material ratio, the main structure of the production equipments have some variations.

Principle of activated coke purification technology

1. Principle of flue gas purification

According to the adsorption characteristics and catalytic properties of activated coke, SO2, O2, and water vapor in the flue gas are adsorbed on the surface of activated coke, then the H2SO4 is generated through reaction on surface and is adsorbed into the micropore of activated coke, so as to achieve the effect of flue gas desulfurization.

2SO2 + O2 + 2H2O → 2H2SO4

The catalytic properties of activated coke is used for selective catalytic reduction (SCR) to denitrate, the NOx is restored to N2 by using NH3 as the reductant

4NO + 4NH3 + O2  → 4N2 + 6H2O
2NO2 + 4NH3 + O2  → 3N2 + 6H2O

2. Mechanism of activated coke’s regeneration

Heat the SO2 saturated activated coke to 400 ℃ -500 ℃, the sulfuric acid or sulfate in the activated coke are decomposed and desorbed, the main decomposition products generated are SO2, N2, CO2, H2O, the physical form is high concentration of SO2 gas, the main reaction is between activated coke and sulfuric acid:

2H2SO4 + C → 2SO2 + CO2 + 2H2O

The activity of activated coke can be restored after regeneration, after regeneration, the adsorption and catalytic ability of activated coke not only do not reduce, but will be improved, but after several times of regenerations, those properties will decrease