การพัฒนาถ่านกัมมันต์จากขี้เลื่อยโรงงานไม้ยางพาราแปรรูปโดยใช้การกระตุ้นด้วยกรดฟอสฟอริกร่วมกับไมโครเวฟในการดูดซับสารอินทรีย์ระเหยภายในอาคาร

Abstract

Development of activated carbon from sawdust obtained parawood manufacture using microwave and phosphoric acid activation for removal of volatile organic compounds include of benzene and toluene was studied in this research. The carbonization temperature of 400, 600 and 800 °C at 1 hour were studied. In this result found that, the temperature for carbonization is 600 °C. The fixed carbon of 76.43% and the yield of charcoal of 18.91% were found. The microwave activation, microwave power at 600, 800 and 1000 watts were studied. 1000 watts is the optimum condition for activation. For the study of phosphoric acid activation, phosphoric concentration of 40, 60 and 80%, microwave power at 1000 watts, and carbonization at 600 °C were studied. The results found that, using 40% of phosphoric acid is suitable for carbonization. In conclusion, the optimum conditions for synthesis of activated carbon from sawdust obtained parawood manufacture for benzene and toluene removal is activation using 40% of phosphoric acid, 1000 watts of microwave, and carbonization at 600 °C. In this condition, BET surface area of 908.59 m2/g, average pore size of 1.67 nm, pore volume of 0.14 cm3/g, and iodine number of 677.89 mg/g were found. The adsorption kinetic of benzene and toluene on activated carbon produced from rubber wood sawdust was conducted at initial concentration of benzene and toluene of 22.93 and 41.15 mg/m3. The equilibrium time of benzene and toluene of 20 hours was found with the adsorption capacity of 0.29 and 0.43 mg/g. The adsorption kinetic of benzene and toluene were found to fit well with pseudo-second order kinetic model. Adsorption efficiency of benzene and toluene are 62.74 and 51.67%. Adsorption isotherms of benzene and toluene were well described by the Freundlich isotherm model. The Freundlich constants of 12.25 and 3.59 mg/g and the empirical constants of 0.27 and 0.64 mg/g were found for benzene and toluene. It is concluded that the adsorption capacity at the surface of the activated carbon was limited. However, this research found that activated carbon that produced from sawdust obtained parawood manufacture by using microwave and phosphoric acid activation can be applied as an alternative forreducing waste from the furniture industry and It can be used effectively for removal benzene and toluene generated in indoor.