Research Progress----Shanghai Advanced Research Institute,Chinese Academy of Sciences

Research Result on Direct Production of Lower Olefins from Syngas Published at Nature

CAS Key Laboratory of Low-Carbon Conversion Science and Engineering Shanghai Advanced Research Institute, now report that under mild reaction conditions (250 oC, 1~5 bar), Co2C nanoprisms catalyse the syngas conversion with high selectivity for the production of lower olefins (60.8 C%).

　　Lower olefins refer to ethylene, propylene and butylene, which are vital building block in the chemical industry. They are fundamental chemicals of the greatest consumption among the organic chemicals all over the world. Large amount of chemical products such as packing materials, cosmetics, synthetic rubber, coatings are the derivatives of lower olefins. In traditional petrochemical industry, lower olefins are mainly derived from oil-based feedstocks. With the rapid depletion of the limited petroleum, there is an urgent need for processes that can produce lower olefins from alternative feedstocks. The syngas, which is a promising alternative feedstock as it can be obtained from reforming of natural gas, gasification of coal or biomass, can be transformed into lower olefins through Fischer-Tropsch to olefins (FTO) process as an attractive alternative non-petroleum-based production route due to its process simplicity and low energy consumption. The primary aims of FTO are to maximize lower olefins selectivity while reduce methane production with high stability. However, the hydrocarbons obtained with the FTO process typically follow the so-called Anderson–Schulz–Flory distribution, which is characterized by a maximum C2-4 hydrocarbon fraction of about 56.7% and an undesired methane fraction of about 29.2%. It is necessary to develop new FTO catalyst which deviate from ASF distribution at mild reaction conditions. Metallic cobalt is the active phase with high FT activity for production of long-chain paraffin. Cobalt carbide is always considered as one of the main deactivation reasons for Co-based FT reaction and produces a large amount of unwanted methane. However, CAS Key Laboratory of Low-Carbon Conversion Science and Engineering Shanghai Advanced Research Institute, Chinese Academy of Sciences, now report that, under mild reaction conditions (250 oC, 1~5 bar), Co2C nanoprisms catalyse the syngas conversion with high selectivity for the production of lower olefins (60.8 C%), while generating little methane (about 5.0 C%), with the ratio of olefin/paraffin amongst the C2-4 products being as high as 30. The product distribution deviates markedly from the classical ASF distribution with the highest selectivity to propylene. Based on study of structure-performance relationship and DFT calculations, a strong facet effect was demonstrated for Co2C nanoparticles during syngas conversion. Specifically, the {101} and {020} facets of Co2C are beneficial for the production of olefins and inhibit the formation of methane (Figure 1).
　　The above research result is recently published at Nature. The high activity, selectivity and stability at mild reaction conditions suggest promising potential industrial application. As Prof. Michael Claeys (one of the reviewers) has said in the NEWS & VIEWS at Nature, “their potential impact cannot be overestimated: they might open up pathways for the development of greatly improved systems for producing valuable chemicals from a variety of carbon sources” and “this is a groundbreaking contribution that further unlocks the immense potential of the Fischer–Tropsch process for producing chemicals. Zhong et al. have thrown open the reaction’s treasure chest, and added fresh momentum to research into methods for making olefins from synthesis gas”.
　　This work has been supported by the Natural Science Foundation of China, the Shanghai Municipal Science and Technology Commission, Shanxi Lu’an Coal Corporation Limited, the Ministry of Science and Technology of China and the Chinese Academy of Sciences.
　　 Figure 1 TEM images of the CoMn catalysts after reaching steady state. (a, b) Low-resolution TEM images. (c-e) High-resolution images of Co2C nanoprisms with exposed facets of (101), (-101) and (020). d, distance (length) of the lattice fringes. (f) The Co2C nanoprism has a parallelepiped shape, with four rectangular faces and two rhomboid faces.
　　Figure 2. Cobalt carbide nanoprisms for direct production oflower olefins from syngas (Nature, 2016, 538, 84）

2016-10-11 more+

China's Carbon Emissions Have Been Overestimated for Over 10 Years

A new paper by a joint research team was published in the prestige science journal Nature on August 20. A press conference hosted by Dr. Nick Campbell, executive editor of Nature, was held on August 19 to announce the results.

　　A new paper by a joint research team comprising scientists from the Shanghai Advanced Research Institute of the Chinese Academy of Sciences (SARI-CAS), Harvard University, Tsinghua University and 21 other research institutions at home and abroad was published in the prestige science journal Nature (Z. Liu, DB. Guan, W. Wei. et al Nature 524, 335–338; 2015) on August 20. A press conference hosted by Dr. Nick Campbell, executive editor of Nature, was held on August 19 to announce the results.
　　In the paper entitled “Reduced carbon emission estimates from fossil fuel combustion and cement production in China,” the joint team reevaluated China’s carbon emissions using updated energy consumption and clinker production data and two new comprehensive sets of measured emission factors for Chinese coal. The “apparent consumption approach” adopted by the team calculates consumption from a mass balance of domestic fuel production, international trade and international fuelling instead of depending upon energy consumption data, which previous studies have shown to be not very reliable. The results are surprising. They show that Chinese CO2 emissions have been substantially overestimated in recent years: In fact, they are 14 percent less than the estimate in the Emissions Database for Global Atmospheric Research (EDGAR) version 4.2 for 2013. (Note that EDGAR has been adopted by the Intergovernmental Panel on Climate Change as the emission baseline.) In addition, over the period from 2000 to 2013, revised estimates are 2.9 gigatonnes of carbon less than previous estimates of China’s cumulative carbon emissions.
　　“At the beginning of the project we thought that the emissions might be higher than existing estimates,” said Zhu Liu, an ecologist at Harvard University and lead author of the study. “We were very surprised,” said Dr. Liu. He noted that according to various emission scenarios intended to limit the global temperature increase by 2？C within this century, China’s room to increase emissions is 25-70 percent more than previously estimated.
　　China is the world's biggest carbon emitter and its emissions account for 25 percent of the entire global amount. However, global CO2 emissions data is mainly provided by various international organizations and databases (e.g., IEA, EDGAR, CDIAC, EIA and CAIT) and China has little influence on these databases. “This is probably the best available estimate of emissions from coal burning in China and that is an important contribution,” said Gregg Marland, a geologist at Appalachian State University and a co-author of the study. The study, funded by Climate Change: Carbon Budget and Relevant Issues, a CAS Strategic Priority Program, will help China to voice its opinions in global energy, economic and environmental policy-making and in international negotiations. In the mean time, the results provide valuable basic data China can use to further carry out carbon emissions reduction and air pollution treatment. Based on the paper, the estimate of how much CO2 will be produced by burning Chinese coal is around 40 percent less per unit than the figures adopted by the Intergovernmental Panel on Climate Change (IPCC). The coal measurements were collected from mine reports and from a project sponsored by the Chinese Academy of Sciences that assesses the country’s cumulative carbon emissions and carbon uptake by ecosystems across China. “All the data is based on real measurement and analysis of more than 700 coal samples from different places in China, which accounts for 97 percent of the national coal emission categories,” said Professor Wei Wei of SARI-CAS. “The lower heating value of Chinese coal reflects its generally low quality and high ash content, and the carbon contained is much lower compared with developed countries and the average world level, which implies that there is not that much CO2 emission in China’s coal.”

2015-08-20 more+

Dr. Lv Min from SARI Awarded GII funding

U.S. and U.K. Governments announced winners of Global Innovation Initiative (GII) recently. Dr. Lv Min from CAS Key Laboratory of Low-Carbon Conversion and Engineering of SARI is one of the awardees. In the following three years, SARI will work closely with Yale University and Heriot-Watt University on the research of high-efficiency reactor and its 3D printing.

2015-07-23 more+

Prof. Mi Xianqiang’s Team Publishes New Findings in Biosensors and Bioelectronics

Biosensor is an important tool for clinical detection, genetic analysis, environmental monitoring, biological terror and national security defense. Recently, researchers have developed a new type of Electrochemical DNA (E-DNA) sensor, which can achieve sensitive detection of target DNA. The result has been published in Biosensors and Bioelectronics

2015-05-27 more+

SARI’s First Key Laboratory Passed Acceptance

On April 8 2015, CAS Key Laboratory of Low-Carbon Conversion and Engineering based in SARI passed the acceptance review organized by Bureau of Frontier Sciences and Education CAS (the Frontier Bureau).

2015-04-20 more+

Joint Lab Established between SARI and Anji Microelectronics

Launching Ceremony of the Joint Lab established between SARI and Anji Microelectronics (Shanghai) Co., Ltd was held on February 9th, 2015.

2015-02-10 more+