Value Maximization of C4 Stream in Petrochemicals Production: Introductions to C4AC and Ole-SIV

Butadiene is extracted from naphtha cracked C₄ to be used in automobiles and appliances. Trouble is, 1~2% of acetylenes are present in the feed and they are impurities in many downstream products. Removal of these acetylenes is costly as they must be diluted for safety concerns. In many applications, butadiene is used as diluent and its loss is inevitable. In addition, acetylenes cause fouling, resulting in a periodic shutdown. To solve such problems, C4AC(C₄ Acetylene Converter) was developed to convert acetylenes to butadiene and raffinate. With C4AC process, the diluent loss is prevented and yield increase can be attained. 

Butanes and various butylenes comprise remaining half of a naphtha C₄ stream. Although they are valuable, most butylenes are blended to mogas due to difficulties in separating them. Ole-SIV is a new adsorption process that effectively separates butylenes from paraffins by adsorption. The proprietary adsorbent traps C₄ olefins while C₄ paraffins pass through. As a result, the Ole-SIV process can significantly reduce total investment cost (up to 30%) and energy consumption (by 20-40%) over conventional distillation processes.