Zhang Yong, General Manager of KaiRui Environmental Technology Co., Ltd.

 

　　On September 13, 2017, the National Development and Reform Commission (NDRC) and 14 other ministries jointly issued a notice titled “Implementation Plan for Expanding Biofuel Ethanol Production and Promoting the Use of Ethanol-Blended Gasoline for Vehicles,” which stipulated that the use of ethanol-blended gasoline would be promoted in Northeast China and other provinces and cities starting in 2017, with the goal of achieving near-universal coverage of ethanol-blended gasoline nationwide by 2020. Nearly a year has passed since the policy was introduced. Currently, refineries are closely monitoring the release of follow-up policies and progress in C4 utilization technologies—particularly the highly sought-after selective polymerization technology—while also actively seeking better ways to utilize C4. Regarding the future prospects for C4 in gasoline blending, this publication’s reporter interviewed Zhang Yong, General Manager of KaiRui Environmental Technology Co., Ltd. (hereinafter referred to as “KaiRui Environmental”).

Reporter | Tang Yin

Interviewee | Zhang Yong

 

Selective Overlapping Gains Attention Under New Policy

 

 

 

　　[CCN] Since the introduction of the national ethanol-blended gasoline policy, selective overlapping technology has attracted significant attention from refining companies. What is the current status of this technology’s development in China?

 

　　【Zhang Yong】The GB18351-2017 standard for E10 ethanol gasoline for automotive use explicitly stipulates that “the volume fraction of ethanol shall be 10% ± 2%, and the intentional addition of other organic oxygenates is not permitted.” Therefore, in principle, no other oxygenates—such as methyl tert-butyl ether (MTBE)—may be intentionally added to the gasoline pool. Selective polymerization technology is a new method for producing high-octane, oxygen-free gasoline blending components from isobutylene. Since existing MTBE units can be retrofitted to produce selective polymerization oil, this technology has attracted significant attention from companies following the introduction of the ethanol gasoline policy. Following the introduction of the new policy, the Sinopec Petrochemical Research Institute (hereinafter referred to as “Petrochemical Research Institute”) swiftly applied its proprietary selective isomerization technology at the Shijiazhuang Refining and Chemical Branch. By retrofitting the original MTBE unit into a 120,000-metric-ton selective isomerization unit (based on C4 feedstock), the institute produced isomerized gasoline that met all expected specifications. It is reported that the Petrochemical Research Institute has already signed technology transfer agreements for selective isomerization with several companies.

 

　　The unit utilizes polymer resin catalysts from KaiRui Environmental Protection. The fact that these catalysts were successfully applied in China’s first selective polymerization unit is inextricably linked to KaiRui Environmental Protection’s more than a decade of research achievements in polymerization technology and polymer resin catalysts. As early as 2003, when the national ethanol-blended gasoline policy was implemented, and in 2004, when the United States began phasing out MTBE, KaiRui Environmental Protection began researching MTBE replacement technologies and catalysts. Ultimately, the company successfully developed polymerization and ethyl tert-butyl ether (ETBE) production technologies, along with supporting catalysts (including isobutylene polymerization resin catalysts, isooctene hydrogenation catalysts, and ETBE synthesis catalysts). Among these, the polymer catalyst has been used in multiple domestic plants in recent years; in 2016, it was exported to India and has been successfully applied in IOCL’s indirect alkylation unit to this day, achieving industrial-scale production. Orders for ETBE polymer catalysts in the European market have become a significant component of KaiRui Environmental Protection’s international trade.

 

　　【CCN】Does this mean that selective polymerization technology can completely replace MTBE plants?

 

　　【Zhang Yong】Selective polymerization technology is the only technical approach under China’s ethanol-blended gasoline policy that can replace MTBE technology and convert isobutene into oxygen-free, high-octane gasoline blending components.

 

　　However, selective polymerization technology still lags behind MTBE in terms of product octane rating, economic viability, and butene separation. MTBE has an octane rating of 115 (RON), which is significantly higher than the 100 (RON) of iso-octane, making it a superior gasoline blending component. Furthermore, the MTBE production process converts methanol into high-octane gasoline, thereby increasing corporate profits. MTBE technology is currently the most effective method for separating isobutene from 1-butene. Selective polymerization technology is not yet capable of replacing MTBE technology to achieve effective separation of isobutene and 1-butene, and the issue of 1-butene loss still persists.

 

 

 

Ethanol Addition to Gasoline: “Blazing a New Trail”

 

 

 

　　[CCN] China’s ethanol-blended gasoline policy was implemented in some regions as early as 2003, but many members of the public have reported that ethanol-blended gasoline still has some issues compared to regular unleaded gasoline. What is your view on this?

 

　　[Zhang Yong] Promoting ethanol-blended gasoline helps optimize the energy structure, improve the ecological environment, and regulate the grain market; it is also an effective way to dispose of grain that has exceeded its shelf life or failed to meet quality standards.

 

　　However, ethanol-blended gasoline also has obvious drawbacks: First, it increases fuel consumption. Data shows that the calorific value of gasoline is 43.03 MJ/kg, that of diesel is 46.04 MJ/kg, while that of pure ethanol is only 26 MJ/kg. Even though ethanol-blended gasoline is not pure ethanol, its calorific value is still lower than that of regular gasoline, at only 39.82 MJ/kg. To maintain the desired power output, the Engine Control Unit (ECU) injects more fuel, leading to increased fuel consumption. Field tests show that using ethanol-blended gasoline increases a vehicle’s fuel consumption by approximately 3.5%. Second, it causes difficulty starting at low temperatures: Ethanol-blended gasoline has a high latent heat of vaporization and absorbs a significant amount of heat, which lowers the operating temperature inside the engine block and makes starting difficult in cold weather. Third, it is more prone to carbon buildup: Due to the high heat of vaporization of ethanol-blended gasoline, when it is injected through the fuel injector onto the back of the intake valve, the temperature there drops. As a result, the gasoline cannot atomize fully, and large molecules form a gummy substance, leading to carbon buildup on the back of the intake valve. Fourth, it is prone to phase separation, making storage and transportation inconvenient: Ethanol is a polar substance. When blended with non-polar hydrocarbons, even trace amounts of water can cause phase separation between the ethanol and gasoline. Furthermore, ethanol gasoline has a shorter shelf life than regular gasoline and is prone to phase separation once it exceeds its shelf life. Due to the tendency of ethanol-blended gasoline to separate, ethanol-blended gasoline blending centers would need to be established in various locations to blend and sell the fuel on-site, thereby increasing transportation and management costs.

 

　　【CCN】Given that ethanol-blended gasoline has so many drawbacks and selective coupling technology cannot completely replace MTBE plants, is there a better technology that can both utilize ethanol and resolve the issues associated with ethanol-blended gasoline and selective coupling?

 

　　【Zhang Yong】Looking at the development of gasoline abroad, ethanol-blended gasoline is not the only way to add ethanol to gasoline. Since 2004, when the United States and European countries discovered that MTBE caused groundwater contamination, they have gradually begun to phase out MTBE and vigorously develop ethanol-blended gasoline and alkylated gasoline. The development of ethanol-blended gasoline in these regions has followed two paths: one is direct addition, as in China, and the other is the use of ETBE. ETBE is produced by reacting ethanol with isobutylene under the action of an acidic catalyst. Compared to MTBE, ETBE has only a slightly lower oxygen content, while all other performance indicators are superior to those of MTBE. In particular, its Reid vapor pressure is lower, making it more miscible with gasoline than MTBE; its solubility in water is less than one-third that of MTBE, resulting in minimal groundwater contamination. The maximum blending level of ETBE in gasoline is 17V%, and ethanol accounts for 45.1 wt% of ETBE. This means that blending ethanol into gasoline in the form of ETBE allows for the addition of approximately 8% ethanol, which is slightly lower than the ethanol blending level of (10±2)V% currently mandated by China’s ethanol-blended gasoline standards. However, utilizing ethanol in the form of ETBE can resolve the issues associated with ethanol-blended gasoline—such as increased fuel consumption, carbon deposits, and phase separation—while also effectively separating isobutene from 1-butene. Furthermore, retrofitting existing MTBE facilities would be simpler and require lower investment costs, making it a solution that achieves multiple benefits at once.

 

 

 

Mature Technology Exported Overseas

 

 

 

　　[CCN] ETBE technology has already been applied in the United States, Europe, and other countries. Are there any industrial-scale facilities in China?

 

　　[Zhang Yong] Due to the relatively high price of ethanol in China, there are currently no industrial-scale facilities, but the technology is mature. China began implementing ethanol-blended gasoline policies in certain regions in 2003, while the United States banned MTBE in 2004. At the time, this represented very unfavorable market news for a company like KaiRui Environmental Protection, which specialized in MTBE process technology transfer and MTBE catalyst production. Kairui Environmental remained highly vigilant in response, actively developing new technologies and catalysts to address the post-MTBE ban era. As early as 2009, the company completed the R&D of ETBE process technology and catalysts and actively participated in numerous international process technology tenders. Currently, Kairui Environmental’s ETBE resin catalysts have been successfully implemented in multiple industrial applications in overseas markets, with satisfactory operational results, and the company has established long-term cooperative relationships with many European enterprises.

 

　　[CCN] In which countries and regions overseas have the company’s ETBE resin catalysts been successfully applied?

 

　　[Zhang Yong] KaiRui Environmental Protection began R&D on ETBE technology and catalysts relatively early. As early as 2010, the company’s ETBE catalysts were already being exported. Currently, they are primarily used in European markets, such as Spain, Germany, and Italy. It is particularly worth noting that KaiRui Environmental Protection has established a long-term partnership with Spain’s REPSOL, and all four of its subsidiaries use KaiRui Environmental Protection’s ETBE resin catalysts.

 

　　Source: *China Chemical Industry Information* magazine