Tobacco dust is by-product of cigarette factory. The existence of impurities on tobacco dust in the form of iron sand (magnetite) and silica for about 10 – 20% (wt%) makes tobacco dust belong to hazardous material. The threshold of sand impurities concentration on Tobacco dust is less than 5% (wt%). One of the methods able to reduce the impurities of tobacco dust is separation process using fluidized fixed bed. Tobacco dusts before and after fluidized were analyzed with gravimetric method to find out the effect of separation process on the sand impurities concentration. The sand impurities concentrations on raw material of tobacco dusts are 28.47; 32.38; and 35.32% (wt%). Further, the optimum gas flow velocity for separation process using fluidized fixed bed was achieved at 0.61 m/s. That velocity generated tobacco dust with the smallest sand impurities at 4% (wt%) in 120 minutes time operation. The subtraction of FTIR wavenumber after separation process (497 cm-1 to 493 cm-1 and 939 cm-1 to 925 cm-1) was denoted as the decrement of sand impurities concentration. Moreover, the loss of Fe-O-Si interaction indicated that the sand impurities concentration was successful to be reduced from the tobacco dust.