Judul: Process design in the production of isoeugenol and vanillin from eugenol of clove leaf oil
Abstrak: Eugenol merupakan komponen utama minyak cengkeh yang kandungannya dapat mencapai 70−95 % tergantung dari bahan baku yang digunakan (bunga, tangkai, dan daun). Dengan kandungan eugenol yang tinggi, minyak cengkeh merupakan sumber bahan baku isoeugenol dan vanilin yang potensial. Tujuan umum penelitian ini adalah menghasilkan rancangan proses produksi vanilin yang berbasis eugenol minyak daun cengkeh yang memiliki kalayakan teknis maupun finansial. Adapun tujuan khusus dari penelitian ini adalah 1) identifikasi isoeugenol dan vanilin hasil sintesis, 2) simulasi rancangan proses industri isoeugenol dan vanilin, 3) kelayakan finansial dan nilai tambah. Adanya penelitian ini diharapkan potensi ekonomis eugenol minyak daun cengkeh (MDC) secara maksimal dapat diusahakan, sehingga dapat memberikan nilai tambah minyak daun cengkeh.
Keyword: clove leaf oil, eugenol, isoeugenol, vanillin, process design, potential raw material

Judul: Process design in the production of isoeugenol and vanillin from eugenol of clove leaf oil
Abstrak: Clove leaf oil contains a high amount of eugenol (70-95%) and hence it has been considered as a potential raw material for production of isoeugenol and vanillin, which have high economic value. This study was aimed at designing production of isoeugenol and vanillin from eugenol of clove leaf oil and analyzing the potential product development financially.The specific objectives of this research work are 1) Identify the isoeugenol and vanillin, 2) Model simulation of process design of isoeugenol and vanillin, 3) Study on financial feasibility and added value. This research is expected to provide maximum economic potential of eugenol to enhance the added value of clove leaf oil. The results showed that the FTIR and NMR products confirmed that isoeugenol and vanillin present in the synthesized product were identical to the reference standards. Model simulation of process design suggested that isomerization reaction of eugenol to produce isoeugenol occurred at temperatures of 25-200oC and 1 atm pressure, with the average conversion and isoeugenol of 90% and product purity of 89,6%. Meanwhile, oxydation of isoeugenol which then produced vanillin took place at temperatures of 19.22-150oC and 1 atm pressure resulting in the average conversion of 90% and product purity of 98%. Financial analysis on isoeugenol and vanillin industries showed feasible at production capacities of 1,157,280 kg/year and 853,929 kg/year respectively, with total investment of Rp. 3,795,050,000 and 3,795,050,000 as well as working capital of Rp. 127,487,726,119 and Rp. 154,794,595,559 respectively. At an interest rate of 12% and 10 years project lifetime showed the NPV of Rp. 645,341,441,970 and Rp. 779,561,530,094 respectively. Furthermore, the IRR were 47,40% and 47,43%; net B/C ratio 3.90 and 3.91; BEP 8,178 and 5,063 products unit; PBP 1.27 and 1.25 years. Value added of eugenol to isoeugenol and vanillin industry were Rp. 145,193 and Rp 175,651/kg respectively, while labor incomes were Rp. 447.0 and Rp. 2.190/kg, processor profits Rp. 144.476 and Rp. 173.461/kg. It is concluded that designing industrial production of isoeugenol and vanillin from eugenol of clove leaf oil is financially feasible.
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Judul: Metrik Einstein (Anti-) Self-Dual Berdimensi Empat dengan Metode Cartan
Abstrak: Gravitational field equation can be formulated in differential forms (differential geometry), which describes gravity as a manifestation of the curvature of space-time. Curvature of space-time is characterized by a metric that satisfies the gravitational field equation. With differential forms it can be formulated the (anti-) self-dual Einstein equation, which is a modification of the Cartan structure in (anti-) self-dual basis. Calculation of (anti-) self-dual metric with (anti-) self-dual Einstein equation is simpler than the calculation using Christoffel symbols.
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