Selection of Isomerization Process to Produce Upgraded Mogas Meeting EURO-IV Standards as per Government Regulations

Abstract

This project aims to select the most suitable isomerization process for producing motor gasoline of desired Research Octane Number (RON) meeting Euro IV standard. For this purpose, UOP Honeywell®’s Penex process is being used here. The whole process occurs in a H2 atmosphere and utilizes a metal-chloride catalyst. Plant is based on light straight run Naphtha feed of approx. 12500 bbl/day which is mixed with H2, perchloroethylene (a catalyst promoter) and recycle stream from DIH. Process operations can be categorized into three sections. The first section is reactor section, where two fixed bed reactors are installed. Following it is a stabilization section where impurities like H2S, NH3 and light hydrocarbons are removed. The third section is a de-isohexanizer/recycle section where unconverted hexanes and methyl pentanes are separated and recycled as they have low RON. Other than isomerization, the reactions occurring include benzene saturation, hydrocracking and ring opening. The final isomerate produced is blended with higher hydrocarbons to give a fuel of RON between 87 and 90. The target reduction in benzene (<1%), Sulphur (<50 ppm), aromatics (<35%) and lead(0.005 g/l) content has been achieved.