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A more cost-effective hydrogenation technology for light cycle oil http://www.oilnews.com.cn/bk/images/070821/A012007011.jpg China Petroleum News Center. It is reported that to date, light cycle oil (LCO), which is produced as a by-product of the desulfurization process of vacuum gas oil, has been used mainly as a component of heavy oil or mixed with straight-run crude diesel (SGO). However, as the demand for heavy oil decreases, the disadvantages associated with using it in combination with LCO – such as its low cetane number – result in a low level of utilization in the market. Furthermore, the existing technologies for hydrogenating LCO are energy-intensive and require a large amount of hydrogen; 1000 L of light cycle oil necessitates 1500 m3 of H2. To address the aforementioned shortcomings, Kawasaki Catalyst Manufacturing Co., Ltd. of Japan developed a new energy-efficient LCO hydrogenation process with the support of the Japan Petroleum Energy Center (JPEC). This process consists of 2 reactors and a fluidized catalytic cracking (FCC) system. The first reactor is used to remove sulfur and nitrogen compounds from LCO at temperatures of 350–400°C, using hydrogen at 10 MPa, in the presence of two catalyst beds – the upper catalyst bed containing Ni and Mo supported on a silica-alumina carrier, and the lower catalyst bed containing Ni and Mo supported on an aluminum-zirconia carrier – as well as to decompose aromatic compounds. H2S is removed in the stripping tower, and then the purified gas stream is fed into the second reactor. In the second reactor, the product obtained from the first reactor is subjected to a hydrogenation reaction at 280–320°C and under 5 MPa of hydrogen pressure, in the presence of a Pt-Pd catalyst supported on USY zeolite; the combination of cracking and hydrogenation improves the cetane number of LCO. In the pilot plant, with a relatively low hydrogen consumption (around 400 m3/kL), the overall yield of this process was 98%. The cetane number of the product was greater than 40, the sulfur and nitrogen contents were below 10 μg/g, and the volume fraction of aromatics was less than 5%.