1.  Background

Ethylene glycol（EG）is the raw material for the production of PET polyester, which is used in textile and packaging，and China is a big user of PET polyester. China's ethylene glycol market has a huge gap. In recent years, the annual import of ethylene glycol is 8 ~ 10 million tons, and there is a rising trend.

At present, ethylene glycol production method is mainly the oil route: ethylene as raw materials, through ethylene oxide ethylene glycol production. The method of preparing syngas from coal and preparing ethylene glycol from syngas is very suitable for the situation of more coal and less oil in China, and has a great development prospect.

2.  R&D Course

Wuzheng Engineering (Shanghai) Co., Ltd. is one of the companies engaged in the research of syngas to ethylene glycol in China. In 2006, the low pressure carbonylation process for syngas to ethylene glycol (STEG-Ⅰ) was successfully developed. The whole process patent was applied for in 2008 and authorized in 2009.

STEG-Ⅰ technology was transferred to Shandong Hualu Hengsheng Group Co., Ltd., and a 50kton/year syngas to ethylene glycol plant was built. It started up in 2012, and so far, the device is producing at full capacity, and the 95% of the EG is used for polyester.

In 2014, on the basis of STEG-I technology, we successfully developed the technology of syngas to ethylene glycol adopting middle-high pressure carbonylation process（STEG-Ⅱ）. We have obtained 5 relevant invention patents, and obtained the full process invention patent authorization in the United States and Russia in 2018. In 2017, the STEG-Ⅱ technology was successfully transferred to Huabin Zhengkai Co., Ltd.

3.  Flow Sheet of STEG-Ⅱ

4.   Reaction Equation

5.  Process Parameters 

6.  Catalyst Performance

7.  Advantages of the Technology

（1）Significantly reduce CAPEX and OPEX;

（2）Reduce energy and material consumption;

（3）Increase the service life of catalysts;

（4）Enhance the production stability.