Light Naphtha Isomerization by JSC SIE Neftehim IsoMalk-2™ Process

Published October 2012

This review presents a technoeconomic assessment of a refinery light naphtha isomerization process based on technical data extracted from the patents of JSC SIE Neftehim. Although we have used the best possible engineering judgment in the conceptualization and design of the process, a commercial JSC SIE Neftehim plant may or may not have the same construct as presented in this review. However, we strongly believe that the presented process design and economic evaluation are a reasonably good assessment of the actual process, and the two should be within the marginal boundaries of error. 

The process involves isomerization of the light naphtha stream from a crude unit in the presence of a heterogeneous catalyst system. The reaction conditions are 130°C and 3 MPa. The catalyst system consists of a proprietary sulfated metal oxide catalyst. The yield of isomerate based on the overall unit is over 98% by weight with light gases as a by-product. The selectivity of the catalyst toward formation of branched-chain isoparaffins is high. The reactant mixture is sent to a series of distillation columns where unconverted material is recycled and the isomerate is obtained by combining isoparaffins-rich streams from various columns. 

Our cost analysis is based upon a 400,000 t/yr plant (11,107 B/SD). We estimate that a plant of that capacity will require a capital investment of about $53.1 million at a US Gulf Coast location. Product value (as defined in the text) is about 16.25¢/lb and the production cost is 14.87¢/lb. Cost details and relevant assumptions are given in the process description section of this review.