VI. DATA PENGAMATAN PEMBUATAN METIL ESTERNoPerlakuan Pengamatan

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VI. PERHITUNGAN

a. Densitas metil ester (a) labu piknometer kosong + termometer = 31 gr (b) labu piknometer + termometer + sampel = 52,7 gr Berat sampel (b-a) = 21,7 gr Vair = Vsampel = = = 25 ml

sampel( praktek) = = = 0,868 gr/ml % kesalahan = = x 100% = 0,64 %b. Kadar asam lemak bebas NaOH = = = 2 gr NNaOH = 0,1 N VNaOH = 0,7 ml BM ALB = 256 gr/mol

Kadar ALB = x 100% = = 0,0896 %

c. Perhitungan reaksi Mol minyakminyak = 0,928 gr/mlvminyak = 200 mlBM minyak = 806 gr/mol

m = x V = 0,928 gr/ml x 200 ml = 184 gr nminyak = = = 0,228 mol Mol metanolCH3OH = 0,79 gr/mlVCH3OH = 41 mlBM CH3OH = 32,04 gr/mol

m = x V = 0,79 gr/ml x 41 ml = 32,39 gr n CH3OH = = = 1,01 mol

Persamaaan reaksi

Penentuan jumlah metil ester teoritis

Trigliserida + 3 metanol gliserol + 3 Biodiesel (dalam minyak)M : 0,228 mol 1,01 mol - -R : 0,228 mol 0,228 mol 0,228 mol 0,228 molA : - 0,782 mol 0,228 mol 0,228 mol

Berat metil ester teoritis = n x BM = 0,228 mol x 284 gr/mol = 64,75 gr

Metil ester praktek Metil ester = 0,868 gr/ml V Metil ester = 25 ml Berat metil ester = 0,868 gr/ml x 25 ml = 21,7 gr % konversi CH3OH = x 100% = = 22,57 % % yield metil ester = x 100% = x 100% = 33,51 %