Konversi Metana Menjadi Syngas Dengan Katalis Oksida Perovskit La₁₋ₓSrₓCo₁₋ᵧFeᵧO₃±δ Melalui Oksidasi Parsial - Methane Conversion To Syngas Over La₁₋ₓSrₓCo₁₋ᵧFeᵧO₃±δ Perovskite Oxide Catalysts Under Partial Oxidation Mechanism

Kedua seri senyawa La1-xSrxCo0,8Fe0,2O3±δ mulai dari x = 0 sampai dengan 0,4 dan senyawa La0,7Sr0,3Co1-yFeyO3δ mulai dari y = 0 sampai dengan 0,4 telah berhasil disintesis dengan metoda solid state. Karakterisasi senyawa pertama La1-xSrxCo0,8Fe0,2O3±δ menunjukkan semakin besar subtitusi Sr terhadap lantanum semakin besar persentase penyusutan, kekerasan, konduktivitas elektrik, fluks ion oksigen, volume kristal, oksigen nonstoikiometri (0,2≤x≤0,4), semakin tinggi koefisien ekspansi termal (0,2≤x≤0,4) dan semakin panjang rusuk sel kristal sedangkan ukuran partikel, kristalinitas, oksigen nonstoikiometri (x≤0,2) semakin kecil dan koefisien ekspansi termal (x≤0,2) semakin rendah. Karakterisasi senyawa kedua La0,7Sr0,3Co1-yFeyO3δ menunjukkan semakin besar substitusi ion Fe terhadap Co semakin besar konduktivitas elektrik, volume kristal, oksigen nonstoikiometri (0,2≤x≤0,4) dan semakin panjang rusuk sel kristal sedangkan persentase penyusutan, kekerasan, ukuran partikel, kristalinitas, fluks ion oksigen semakin kecil dan koefisien ekspansi termal semakin rendah. Uji aktivitas katalis dibuktikan melalui pembentukan syngas dari reaksi oksidasi parsial metana tanpa adanya gas oksigen pada suhu 950°C. Seri senyawa La1-xSrxCo0,8Fe0,2O3±δ menunjukkan semakin banyak lantanum yang tersubstitusi oleh strontium semakin besar selektivitas terhadap CO maupun H2 sedangkan konversi CH4, selektivitas terhadap CO2 dan rasio H2/CO semakin kecil. Seri senyawa kedua La0,7Sr0,3Co1-yFeyO3δ menunjukkan semakin besar kobalt yang tersubstitusi oleh besi semakin besar konversi metana dan selektivitas terhadap CO dan H2 sedangkan selektivitas CO2 dan rasio H2/CO semakin kecil. ============================================================Both series of compounds La1-xSrxCo0,8Fe0,2O3±δ ranging from x = 0 to 0.4 and compound La0,7Sr0,3Co1-yFeyO3δ ranging from y = 0 to 0.4 had been successfully synthesized by the method of solid state. Characterization of the first series compound showed the more the Sr substitution of La in the La1-xSrxCo0,8Fe0,2O3±δ the larger the shrinkage, the hardness, the electrical conductivity, the oxygen flux, the crystal cell volume, the oxygen nonstoichiometry (0,2≤x≤0,4), the higher the hardness and the thermal expansion coefficient (0,2≤x≤0,4), the smaller the particle size, the crystallinity, the oxygen nonstoichiometry (x≤0,2) and the coefficient of thermal expansion (x≤0,2). Also, Sr substitution for La increased the unit cell length. The characterization of the second compounds showed the more the Fe substitution of Co in the La0,7Sr0,3Co1-yFeyO3δ the greater the electrical conductivity, the crystal cell volume, the oxygen nonstoichiometry (0,2≤x≤0,4), the smaller the shrinkage, hardness, particle size, crystallinity, the oxygen flux and the lower the coefficient of thermal expansion. Besides, Fe substitution for Co led to the increase the unit cell length of La0,7Sr0,3Co1-yFeyO3δ. The catalyst activity test was evidenced by the formation of syngas from partial oxidation of methane in the absence of oxygen at a temperature of 950°C. The La1-xSrxCo0,8Fe0,2O3±δseries showed the more La partially substituted by Sr the greater the selectivity to CO and H2, the smaller the CH4 conversion, the selectivity to CO2 and the ratio of H2/CO. The La0,7Sr0,3Co1-yFeyO3δ series showed the more Co partially substituted by Fe the greater the conversion of methane, selectivity to CO and the smaller the selectivity to CO2 and the ratio of H2/CO