Rekayasa pembuatan faktis gelap dari minyak jarak (Castor Oil)

Abstract

Factice is one of processing aid used in rubber finish product manufacturing. Dark factice made by vulcanization of saturated vegetable oil with adding sulfur in high temperature. Dark factice is added in rubber compound that will be extruded and printed. Castor oil has the characteristics that qualify as a raw material of dark factice. The aim of this study was to get the valid information regarding: (1). the characteristics of castor oil as a raw material of dark factice, (2). optimum process conditions (sulfur concentration and temperature) to make dark factice from castor oil, (3). quantitative description of cross-linking formation in the dark factice making from castor oil and application of dark factice that used in LPG tube making, (4). pre-feasibility study (technical and financial) of establishment dark factice-castor oil based production unit. The results showed castor oil having iodine numbers of 85.9 g iod /100 g oil that qualifies to be processed into a dark factice. The optimization used response surface method showed the optimum concentration of sulfur was 27.5 pho (part per hundred oil) and temperature was 165oC. Dark factice made from optimum treatment showed the following characteristics : extract of petroleum ether 11.5 %, free sulfur content 1.83%, ash content 4.25%, and pH 7.36. Based on those characteristics, the dark factice made could be categorized as first grade dark factice. The analys is of FTIR spectrum and cross-link density of dark factice, suppo rt the allegation of cross-linking formation during the formation of dark factice. The application of dark factice to make LPG tube reduced the compounding time and increased the extrusion rate. Based on the production capacity of 5 000 kg castor oil/da y, production unit of dark factice derived from castor oil was feasible to be established with IRR and B/C respectively 57.07% and 5.95. The investment of dark factice-production unit establishment was expected to be returned after 21 months.

Fakt is gelap merupakan salah satu bahan oleh karet yang berupa bahan padat dan bertekstur elastis. Faktis gelap dibuat dari minyak yang ba nyak mengandung asam lemak tidak jenuh melalui reaksi vulkanisasi dengan sulfur pada suhu tinggi. Faktis gelap digunakan pada pembuatan kompo n untuk barang jadi karet berwarna. Faktis gelap umumnya ditambahkan pada kompon karet yang aka n dieks trusi ataupun dicetak. Tujuan da ri pe nelitian ini ada lah untuk mendapatka n informasi yang valid tentang : (1) : karakteristik minyak jarak sebagai bahan baku pembuatan faktis gelap, (2) kombinasi konsentrasi sulfur dan suhu optimum untuk pembuatan faktis gelap dari minyak jarak serta karakteristik faktis gelap yang dihasilkan, (3) gambaran kuantitatif terjadinya ikatan silang pada reaksi pembentukan faktis gelap dari minyak jarak dan aplikasi faktis gelap yang dihasilkan dalam pembuatan selang gas LPG, dan (4) gambaran kelayakan teknis dan finansial pengembangan unit produksi faktis gelap berbahan baku minyak jarak.