Prarancangan Pabrik Etilen Oksida dari Etilen dan Udara dengan Kapasitas 100.000 Ton per Tahun

Satrio Samuel Priambodo, Ir. Sutijan, M.T., Ph.D.

2026 | Skripsi | TEKNIK KIMIA

Etilen Oksida merupakan senyawa intermediat kimia yang sangat strategis dalam industri petrokimia, khususnya sebagai bahan baku utama pembuatan etilen glikol, surfaktan non-ionik, etanolamina, dan berbagai produk turunan hilir lainnya. Pabrik Etilen Oksida dari etilen dan udara ini dirancang dengan kapasitas 100.000 ton/tahun dan direncanakan beroperasi secara kontinu selama 330 hari dalam setahun. Pabrik ini berlokasi di Kawasan Industri Krakatau (KIEC), Cilegon, Banten, dengan pertimbangan kedekatan logistik dengan produsen utama bahan baku etilen domestik seperti PT Chandra Asri Petrochemical dan PT Lotte Chemical Indonesia, serta ketersediaan infrastruktur utilitas dan sarana transportasi laut yang memadai melalui Pelabuhan Merak.

Proses produksi yang digunakan adalah metode oksidasi parsial langsung etilen fase gas menggunakan udara bebas sebagai agen pengoksidasi dengan bantuan katalis berbasis perak. Reaksi dilangsungkan di dalam Reaktor Fixed-Bed Multitube yang beroperasi secara eksotermis pada suhu 250 C dan tekanan 25 atm. Untuk mengendalikan panas reaksi yang tinggi dan mencegah terbentuknya titik panas (hotspot) yang dapat menonaktifkan katalis, digunakan fluida pendingin Dowtherm A pada sisi shell reaktor. Campuran gas panas keluaran reaktor didinginkan dan dialirkan ke menara Absorber untuk menyerap etilen oksida secara counter-current dengan pelarut air proses, menghasilkan aliran cairan kaya etilen oksida (Rich Cycle Water). Larutan tersebut kemudian dialirkan ke menara Stripper (Desorber) yang beroperasi pada tekanan rendah (1,5–2 atm) untuk memisahkan etilen oksida dari air sirkulasi. Tahap pemurnian akhir dilakukan di Menara Distilasi utama yang beroperasi pada tekanan 4–5 atm guna memisahkan air sisa dan gas ringan, menghasilkan produk Etilen Oksida cair murni dengan kemurnian komersial minimal 99,5%. Untuk memenuhi kapasitas rancangan, diperlukan laju alir massa bahan baku etilen sebesar 9.528,94 kg/jam dan udara sebesar 40.504,16 kg/jam. Pendirian pabrik ini diharapkan secara nyata dapat mereduksi ketergantungan Indonesia terhadap impor etilen oksida, menghemat devisa negara, serta memperkuat pohon industri petrokimia nasional. 

Ethylene Oxide is a highly strategic chemical intermediate in the petrochemical sector, serving as the essential raw material for manufacturing ethylene glycol, non-ionic surfactants, ethanolamines, and various other downstream derivatives. This preliminary design of an Ethylene Oxide plant from ethylene and air is projected with a production capacity of 100,000 tons/year and is scheduled to operate continuously for 330 days a year. The plant is strategically located in the Krakatau Industrial Estate Cilegon (KIEC), Banten, considering its close logistical proximity to major domestic ethylene suppliers, namely PT Chandra Asri Petrochemical and PT Lotte Chemical Indonesia, as well as the availability of robust utility infrastructure and maritime transport links via Merak Port. 

The production process employs the direct partial oxidation of gas-phase ethylene using atmospheric air as the oxidizing agent over a supported silver-based catalyst . The highly exothermic reaction is carried out inside a Fixed-Bed Multitube Reactor operating at 250oC and 25 atm. To effectively manage the reaction heat and prevent the formation of localized hotspots that could deactivate the catalyst, Dowtherm A is circulated as a coolant on the shell side of the reactor. The effluent gas mixture from the reactor is cooled and directed to an Absorber column, where ethylene oxide is absorbed counter-currently using process water as a solvent, yielding an ethylene oxide-rich stream (Rich Cycle Water). This solution is subsequently transferred to a Stripper (Desorber) column operating at low pressure (1.5–2 atm) to separate ethylene oxide from the recycled water. The final purification stage is conducted in a primary Distillation Column operating at 4–5 atm to remove residual water and light gases, successfully delivering liquid Ethylene Oxide with a minimum commercial purity of 99.5% by weight. To meet the specified design capacity, the plant requires a mass flow rate of 9,528.94 kg/hour for ethylene and 40,504.16 kg/hour for air. The establishment of this plant is expected to significantly reduce Indonesia's reliance on ethylene oxide imports, preserve foreign exchange reserves, and promote the structural integration of the national petrochemical industry from upstream to downstream. 

Kata Kunci : Etilen Oksida, Etilen, Oksidasi Langsung, Udara, Reaktor Fixed-Bed Multitube/Ethylene Oxide, Ethylene, Direct Oxidation, Air, Fixed-Bed Multitube Reactor, Cilegon