Hiroki YAMAUCHI
Development of solid acid catalyst for production of liquid fuel from deproteinized natural rubber
Kazunori SATO
In aiming at developing catalysts for the efficient production of gasoline-like liquid fuel from deproteinized natural rubber being a polymer with isoprene structure, the effects of solid acid catalysts were studied. Three kinds of acid catalysts such as SiO2-Al2O3, SO4/ZrO2 and SiO2 were used. SiO2-Al2O3, SO4/ZrO2 were prepared by a sol- gel method. Furthermore, Pd, Pt or Ni -deposited acid catalysts were used. The catalytic activity of converting deproteinized natural rubber to liquid fuel was investigated in a nitrogen gas atmosphere of 1 MPa in a batch type reaction system using an autoclave. The reaction was carried out in a reaction mixture of catalysts and natural rubber without solvents. The catalytic cracking of deproteinized natural rubber at 573 K produced a yellow-color liquid. The main products were alkyl aromatic hydrocarbons including toluene, p-xylene and 1-methyl-4-[1-methylethyl]-benzene. The comparison of catalytic activity among the acid catalysts showed that SiO2-Al2O3 had the highest activity for the total conversion of natural rubber and also high efficiency with the production of liquid phase products. The effects of metal addition on SiO2-Al2O3 showed that Pd and Pt provided higher catalytic activities than did Ni. In the NH3 temperature programmed desorption (TPD), SiO2-Al2O3 exhibited a NH3 desorption peak at a high temperature, indicating that SiO2-Al2O3 involved strong acid sites which was responsible for high catalytic activity. For Pd supporting SiO2-Al2O3, the TPD results showed that the acid strength of SiO2-Al2O3 was weakened slightly, whereas the promotion of dehydrogenation and hydrogenation by the presence of the Pd metal occurred. It was proposed that the catalytic activity was improved by two functional roles of metal and acid sites, and Pd supporting SiO2-Al2O3 is concluded to be a catalyst suitable for efficient conversion of deprotenized natural rubber into liquid fuel
Please use "previous botton" to return the previous page