Hydrogenation of coconut oil into Biofuel (bio-jet fuel and high-value low molecule hydrocarbons)

Abstract

The performance of Ni/HZSM-5, HZSM-5, and without a catalyst have been investigated for the hydrogen pressure range of 10-40bar hydrocracking of coconut oil in a packed-bed tubular reactor between 300-450°C. This study concentrates on the effect of the operating parameters (reaction pressure, type of catalyst and reaction temperature) on the yield of transportation fuel carbon range (C5-C22) using the One-Variable-At-A-Time approach. The objectives of this study are to evaluate the effect of process conditions which includes: temperature, pressure, and presence of a catalyst, and to compare the activity of Ni/HZSM-5, HZSM-5 and without catalysts. All tested catalysts were effective in attaining biofuel range in the liquid product. The highest yield and performance of gasoline liquid composition 83.03% was obtained from the reaction pressure at constant temperature of 450 ͦC in 40bar where HZSM-5 catalysts was used, the yield of gasoline liquid composition 82.25% was also produced at constant pressure of 40 bar in 300 ͦC where promoted catalyst(Ni/HZSM-5) was used. Hydrocracking coconut oil under Ni/HZSM-5 catalysts produced the highest yield of jet fuel liquid compositions 78.73% at constant temperature 300°C, and pressure of 10 bar, this was due to less coke that was formed within a reactor and less temperature of 300°C. The highest yield of jet fuel liquid composition 75.67% was also produced at constant pressure of 10 bar at muximum temperature of 450 ͦ C, this was also due to less coke that was formed within a reactor where HZSM-5 was used because of less pressure applied. For the highest yield of diesel liquid composition 24.04%, constant temperature at 400 ͦC of 20 bar where Ni/HZSM-5 was used in figure:5-9 and the highest yield of diesel liquid composition 25.15% was also produced at constant pressure of 20 bar in 450 ͦC where HZSM-5 was used. X-Ray Diffraction (XRD), Scanning Electron Microscope (SEM) coupled with Energy- dispersive X-ray spectroscopy (EDS) analyses were employed for catalyst characterization. XRD patterns confirm the success of metal doping on ZSM-5. Major peaks at 9.1° and 22.9° corresponding to ZSM-5 crystals were observed in ZSM-5. Impregnation with metals reduced the crystallinity of ZSM-5 supported catalysts.