Raw and pure NaHCO3 were modified mech. by milling or chem. by adding Na2CO3 center dot 1.5H(2)O(2) (10% by mass), CaO2 (10% by mass) or urea (0.5% by mass) and introduced into the exhaust gas channel. The fired coal contained S 1.28% and Hg 120.1 ng/g. The mercury contents in the fuel and sorbent, and mercury mass emitted to the atm. for the processes conducted with and without use of the sorbent were detd. The assays were performed for Na/S mass ratios 0.75 or 3. The best efficiency of the Hg removal from flue gases was achieved for the mech. modified raw NaHCO3 and pure NaHCO3 (61% and 70%, resp.) both for the Na/S mass ratio 3.