Marieska Verawaty
Department of Biology, Faculty of Mathematic and Natural Sciences, Sriwijaya University

Published : 2 Documents

Found 2 Documents

Calcium Oxide Decomposed From Chicken’s and Goat’s Bones as Catalyst For Converting Discarded Cooking Oil to be Biodiesel Lesbani, Aldes; Susi, Yosine; Verawaty, Marieska; Mohadi, Risfidian
Aceh International Journal of Science and Technology Vol 4, No 1 (2015): April 2015
Publisher : Graduate School of Syiah Kuala University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.13170/aijst.4.1.2124


Thermal decomposition of calcium oxide from chicken’s (Gallus gallus domesticus) and goat’s (Capra Hircus Aegragus) bones was prepared at temperature variations of 400, 500, 800, 900, 1000, and 1100 oC respectively. X-ray diffractometer (XRD), FT-IR and SEM were used for calcium oxide characterization. XRD diffraction pattern of the bone’s after thermal decomposition at 1100oC has similarity to the XRD standard diffraction pattern from Joint Committee on Powder Diffraction Standard (JCPDS). Diffractions of 2q values being used are 34.2o, 37.3o, 58.3o, 64.1o, and 67.3 o.  Ca-O presence in the samples was detected by FT-IR characterization at wavenumber of 354,90 cm-1. SEM profile show reducing size of bones after decomposition in both chicken’s and goat’s bones. Furthermore, the prepared calcium oxide was applied for biodiesel synthesis from discarded cooking oil through transesterification reaction. By applying the catalysts decomposed from chicken’s and goat’s bones, the biodiesel product showed characteristics as follows: biodiesel applied the chicken’s bone catalyst has fatty acid number of 0.56 mg/KOH, iod number of 22.41 g I2/100 g KOH, density of 0.88 g/cm3 and viscosity of 5.91 mm2/s, while biodiesel applied the goat’s bone catalyst has 0.56 mg/KOH, iod number of 21.57 g I2/100 g KOH, density of 0.88 g/cm3 and viscosity of 6.34 mm2/s. Those biodiesel’s characteristic values meet the National Standard of Indonesia (SNI) for biodiesel.
Catalytic Desulfurization of Benzothiophene Using Keggin Type Polyoxometalates as catalyst Lesbani, Aldes; Marpaung, Arianti; Verawaty, Marieska; Amalia, Hesti Rizki; Mohadi, Risfidian
The Journal of Pure and Applied Chemistry Research Vol 4, No 1 (2015)
Publisher : Chemistry Department, The University of Brawijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21776/ub.jpacr.2015.004.01.202


Performance of catalytic desulfurization of benzothiophen (BT) was studied using polyoxometalates as catalyst. Polyoxometalates H3[a-PW12O40] and  H4[a-SiW12O40], have different heteroatom in Keggin structure and catalytic activities. Polyoxometalates H3[a-PW12O40] and  H4[a-SiW12O40] have high crystallinity with homogeneous distribution particles. Desulfurization of BT using polyoxometalates H3[a-PW12O40] and H4[a-SiW12O40] resulted % conversion up to 99% for 3 h reaction time and at temperature 40 oC. Application of polyoxometalates H3[a-PW12O40] and H4[a-SiW12O40] for crude oil desulfurization showed % conversion of 4-88%. The main functional groups of polyoxometalates still retained after catalytic desulfurization indicated the stability of polyoxometalate compounds