Removal of Formaldehyde from Air Using Modified Bone Char

Formaldehyde (CH2O) is one of the toxic volatile organic compounds which must be removed from polluted air. One of the techniques available to remove is by use of adsorbents. The aim of this study was to evaluate the characteristics and adsorption capacity of modified black bone char (BBC) on CH2O vapor. Subjects and

In this experimental research two types of BBC adsorbents (nomal and modified) were produced. Specific surface area and pore volume of the adsorbent materials were determined using the Brunauer-Emmett-Teller (BET) surface area. The adsorbents structures were analyzed using scanning electron microscopy. The composition of BBC and modified BBC were analyzed by energy dispersive X-ray (EDX) measurement. To investigate breakthrough characteristics and adsorption capacity according to inlet concentration of CH2O on bone chars، adsorption experiments were carried out at 25±1oC under the same conditions.

The specific surface area and pore volume for modified BBC (118. 58m2/g and 0. 374 cm 3/g) were higher than for BBC (105. 24m2/g and 0. 367 cm3/g). The EDX analysis showed that amount of calcium of the modified BBC was less than that of BBC. The results also showed that mean value of equilibrium time of modified BBC was longer than that of BBC (P<0. 05). Moreover، the mean value of adsorption capacity of modified BBC was higher than that of BBC (P<0. 05).

The modification of black bone char promotes porosity and adsorption capacity and can increase the removal efficiency of CH2O in air.