| dc.description.abstract | The effect of MgO on the impregnation of mesoporous silica and its application
as a catalyst in castor oil transesterification by varying the mass of catalyst used has
been studied. Mesoporous silica was synthesized from tetraethylorthosilicate (TEOS)
as a silica source and ricinoleate methyl ester as a template. In the impregnation
process, mesoporous silica was mixed with Mg(NQ3)2.6H20 solution (as MgO 30%)
and stirred for 8 hours at room temperature then dried in an oven and calcined at
65D°C for 8 hours. The resulting product was then applied as a catalyst in the
transesterification of castor oil with variations in the mass of catalyst used, namely
I%, 2%, 3% of the mass of castor oil. The reaction lasted for 4 hours at 65°C using
methanol. The impregnated product was characterized by FT-IR, XRD, SEM-EDX and
BET. FT-IR data showed the presence of silanol (Si-OH) and siloxane (Si-0-Si) groups
which are characteristic of silica material and the appearance of absorption at wave
number 408,91 cm-1 which is the peak of Mg-0 group. XRD data showed that the
material was amorphous and had decreased intensity and shifted the main peak of the
diffractogram towards a smaller 20 diffraction angle and the appearance of a typical
peak of MgO at a 20 angle of 30,34°. SEM-EDX results supported the presence of
MgO metal oxide formed. BET results showed a type IV isotherm curve and a type H3
hysteresis loop. The dominant pore size in silica material before and after
impregnation was 14,27 nm and 15,4536 nm which belongs to the mesopore size of
silica. Based on the data above, it can be concluded that the impregnation of MgO on
silica material has been successful. The product of castor oil transesterification was
characterized by FT-IR and GC-MS. The FT-IR spectrum showed the formation of
ricinoleate methyl ester which was indicated by the appearance of stretching
vibrations of the C-0-C group at wavenumber 1237,5 cm·1
, 1162,9 cm·1 and 1028,7
cm-1
. Based on the GC-MS results of the three variations, the best results were
obtained on the MgO/MS 2% catalyst with ricinoleate methyl ester conversion of
83.09%. | en_US |
