Thermal Oxidative Stability of Biodiesel/Petrodiesel Blends by Pressurized Differential Scanning Calorimetry and Its Calculated Cetane Index

Diesel fuel mixtures with high concentrations of biodiesel have been investigated to analyze the technical feasibility of their use in diesel cycle engines regarding thermal and oxidative properties. The results of combined techniques of oxidative stability, high Pressurized Differential Scanning Calorimetry (P-DSC), Calculated Cetane Index (CCI), and calorific power were used to verify the effect of the thermal-oxidative stability as a function of the percentage of biodiesel in the mixtures. The obtained results evidenced that the thermal and oxidative stability decreased with the addition of biodiesel from 50 to 5% v/v. Low stability fuels require rapid use as the oxidation compounds degrade the product and impair vehicle performance, as well as lead to corrosion and clogging problems in various mechanical systems.

Evaluation of Diethyl Ether (DEE) as a Renewable Transport Fuel in Sudan

This study was conducted to investigate physicochemical properties, copper corrosion test and test the diesel engine performance of diethyl ether diesel blend fuel. With aid of distillation characteristic, the blends percentage were selected as DEE5%, DEE10, DEE15 and DEE20%. Stabinger Viscometer apparatus was used to determine the Kinematic viscosities, Digital Density Analyzer was used to determine the densities. ASTM D 4737 – 03 Test Method are used to determined calculated Cetane index. Copper strip corrosion device was used to determine corrosiveness of copper from diesel and DEE diesel blends. A single cylinder, four stroke diesel engines, mounted on a moving frame was used to conduct the engine test. From the study result we found that that blends physicochemical properties improved with diethyl ether ratio increased in the blends. While Cetane Index increased with diethyl ether ratio increased. At the higher load, the best result of Break thermal efficiency found at DEE10%, where at the low load, the best mechanical efficiency found at DEE5%, DEE15% and DEE20 and at the higher load, the best mechanical efficiency found at DEE20%, on other hand at the low load, the best specific fuel consumption found at DEE15%, While at the higher load the best specific fuel consumption found at DEE10%. Due to availability of diethyl ether in Sudan, diethyl ether can be used up to 10% in diesel blend with no further changed in diesel engine design, and this can be contributed to overcome the diesel fuel crisis in Sudan, but further information and studies are needed for diethyl ether transportation and blending facilities, beside study the effect the addition of diethyl ether on diesel price.

A ANALISA KUALITAS AUTOMOTIVE DIESEL OIL (ADO) SESUAI DENGAN BAKU MUTU YANG BEREDAR DI MASYARAKAT

Automotif Diesel Oil (ADO) adalah bahan bakar jenis distilat berwarna kuning kecoklatan yang jernih, sedikit lebih kental dari pada minyak tanah atau kerosine, dengan trayek didih berkisar antara 180 oC sampai 370 oC, digunakan sebagai bahan bakar untuk mesin diesel berkecepatan tinggi (lebih besar dari 1000 rpm), seperti : kendaraan umum, truk, trailer, alat-alat penggusur tanah, traktor, kereta api, dll. Automotif Diesel Oil (ADO) disebut juga gasoil atau HSD (High Speed Diesel Oil). Tujuan dari evaluasi kualitas Automotif Diesel Oil (ADO) ini yaitu untuk tahu apakah Automotif Diesel Oil (ADO) yang beredar di masyarakat memenuhi syarat pemasaran terutama peruntukan automotif atau mesin diesel. Beberapa parameter uji yang dilakukan, yaitu berupa : Berat Jenis (spesific gravity), Sifat Pembakaran (ignation quality), dan Sifat Penguapan (volatility). Hasil pegujian bahan bakar ADO dari berbagai SPBU memberikan gambaran bahwa sifat atau karakteristik minyak ADO yang diteliti umumnya masih memenuhi spesifikasi baik digunakan sebagai bahan bakar mesin diesel maupun persyaratan transaksi dan transportasi. Dari hasil analisa Spesific Gravity berada di range 0,820 - 0,870, yaitu 0,850 sampai dengan 0,852. Untuk Analisa Sifat Pembakaran dengan Metode Calculated Cetane Index (CCI) ASTM D-976 dimana rata-rata cetane index berkisar 47 - 48 yaitu diatas spesifikasi (min 45). Analisa Sifat Penguapan dengan metode distilasi ASTM D-86 menunjukkan bahwa temperatur FBP memenuhi spesifikasi yaitu < 370oC.