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

Hybrid Energy System Proposed for a Coal-Based Chemical Industry

Recently, a joint research team proposed a hybrid energy system which integrates nuclear/ renewable energy with coal for a coal-based chemical industry. The latest result was published in the famous scientific journal Joule.

　　Recently, a joint research team from CAS Key Laboratory of Low-Carbon Conversion Science & Engineering of Shanghai Advanced Research Institute (SARI) and SARI-ShanghaiTech University Joint Lab has proposed a hybrid energy system that integrates nuclear/ renewable energy with coal for a coal-based chemical industry. The latest result was published in the famous scientific journal Joule under Cell Press journals on March 14th 2018.
　　The coal to chemicals process by gasification is one of the major carbon conversion technologies, especially in coal- rich countries such as China and the United States. The conventional coal utilization pattern, however, causes a large amount of CO2 emission .
　　Nuclear/ renewable energy can supply heat and electricity for low/high temperature water electrolysis, then the hydrogen will be mixed with the syngas from the coal gasification unit to adjust the H/C ratio for downstream chemicals synthesis processes. In this case, the water- gas shift unit can be eliminated and then the system direct CO2 emission can be significantly reduced. Thus, the hybrid energy system is proposed as a way to mitigate the carbon emission as an effective solution to integrate nuclear/ renewable energy with coal for low-carbon fuel and chemicals production.
　　The hybrid energy system is feasible in most coal- intensive countries and will lead to significant carbon emission reduction potential in the coming 5~15 years. Moreover, with the sharp decline of power cost from renewable/ nuclear energy and the carbon tax introduction, the hybrid system shows potential to become economically competitive. It is estimated that in 2030, the reduction capacity of CO2 emission from hybrid systems is equivalent to 90% of the Japanese CO2 emission (1,345 Mt) in 2014 and 33% of the European CO2 emission (3,696 Mt) in 2014.
　　Figure: the proposed hybrid energy system (image by SARI)
　　In the past few years, the CAS Key Laboratory of Low-Carbon Conversion Science & Engineering has made a series of achievements in the low carbon hybrid energy strategy area. Following the related research results published in Science China, Angew Chem Int Ed , Applied Energy, and Energy Conversion and Management, this work, supported by Chinese Academy of Sciences and SARI’s strategic partner Shell, is another achievement of research and education integration between SARI and ShanghaiTech University, which is also a landmark for the construction of Zhangjiang Comprehensive National Science Center.
　　

2018-03-15 more+

Researchers Develop New Electrocatalysts to Convert CO2 into Value-added Chemicals

Conversion of carbon dioxide (CO2) into fuels and chemicals by electroreduction has attracted significant interest, although it suffers from a large overpotential and low selectivity. A Pd-Sn alloy electrocatalyst was developed for the exclusive conversion of CO2 into formic acid in an aqueous solution.

　　Greenhouse gas carbon dioxide (CO2) is widely considered to be responsible for the climate change, and its utilization as an alternative carbon feedstock may be a viable approach for its remedy. Consequently, electrochemical conversion of CO2into value-added chemicals or fuels has attracted significant interest, although it suffers from a large overpotential and low selectivity.
　　Recently, a joint research team from CAS Key Laboratory of Low-Carbon Conversion Science & Engineering of Shanghai Advanced Research Institute (SARI) and SARI-ShanghaiTech University Joint Lab has found a new electrocatalyst to exclusively convert CO2 to formic acid, a chemical widely used in medical, chemical and agricultural lines all over the world over the supported Pd-Sn alloy, and thereby realizing the utilization of CO2 as an affordable carbon resource. This is attributed to the tuning of surface electronic structures of supported Pd-Sn alloy NPs. The electrocataytic activity and selectivity are highly dependent on the surface configurations, in which formic acid with the faradaic efficiency of 99% at the lowest overpotential of -0.26 V was produced on the PdSn alloy surface with optimal surface Pd, Sn and O configuration.
　　On the other hand, the research team has developed a class of mesoporous nitrogen-doped carbon (N-Carbon) tailored with highly uniform cylindrical channel structures to dramatically boost C-C bond formation in CO2 electroreduction. The as-prepared metal-free N-carbon catalyst can convert CO2 into ethanol with the faradaic efficiency as high as 77% at the low potential of ？0.56 V (vs. RHE). As the competitive CO2 reduction into carbon monoxide or other products was completely suppressed, an almost 100% selectivity to ethanol was achieved. This work will open up an avenue for developing robust metal-free carbon-based electrocatalysts for converting CO2 into C2 compounds with high selectivity and efficiency.
　　The latest result was published in the famous scientific journal Angewandte Chemie International Edition (doi: 10.1002/anie.201707098; doi: 10.1002/ange.201706777).
　　Electrocatalytic conversion of CO2 into ethanol over nitrogen-doped carbon catalysts (Image by SARI)
　　This work was supported by the Hundred Talents Program of Chinese Academy of Sciences, the Ministry of Science and Technology, the SARI-ShanghaiTech Low-carbon Joint Lab, and the SARI Innovation Fund.

2017-08-29 more+

A Big Step Forward in Greenhouse Gas Conversion

A demonstration project of producing syngas from carbon dioxide has passed an industrial demonstration in north China’s Shanxi Province recently. It’s the world’s largest production test plant of Mnm3/h scale CO2-CH4 reforming.

　　A demonstration project of producing syngas from carbon dioxide has passed an industrial demonstration in north China’s Shanxi Province recently. The demonstration plant, which is co-launched by Shanghai Advanced Research Institute, Chinese Academy of Sciences (SARI-CAS), Shanxi Lu’an Coal Corporation Limited and Shell Global Solutions International, can produce more than 200,000 normal cubic meters of the syngas and convert 60 tons of carbon dioxide daily. It’s the world’s largest production test plant of Mnm3/h scale CO2-CH4 reforming. As of last Sunday, it had been operating stably for more than 1,000 hours.
　　Carbon dioxide and methane are typical greenhouse gases and key carbon resources. Converting the greenhouse gases to syngas of carbon monoxide and hydrogen, known as "drying reforming of methane," is receiving increasing attention because its "great incentives" in environment protection.
　　"Compared with traditional steam reforming, the dry reforming almost does not consume water, but uses the greenhouse gases," said Dr. Zhang Jun, a leading researcher of the project.
　　However, two of the biggest challenges to apply the dry reforming at an industrial scale lie in the catalyst that can resist severe carbon deposition and its special reactor. The issues were resolved through a "highly stable nanocomposite catalyst" developed by the research team, which could not only resist carbon deposition and agglomeration but also in perfect match with the special reactor. The technology can be applied on offshore natural gas, shale gas that contains large amount of carbon dioxide, as well as in traditional coal chemical industry.
　　 “We have independent intellectual property rights of “dry reforming”, said Prof. Sun Yuhan, Project Leader of the project. “The stable operation of the demonstration is a successful example for cooperation between three parties from basic research to engineering demonstration. The technology not only lays an important technical foundation for large-scale utilization of natural gas, but also contributes to the low-carbon development of Shanxi coal chemical industry.”
　　The three parties are planning to promote the technology’s commercialization worldwide.
　　 dry reforming demonstration plant in Shanxi Province (image by SARI)

2017-08-15 more+

CO2-to-Acrylate: a Dream Reaction for 40 years

A new review article on the subject of converting CO2 and ethylene to acrylic acid and derivatives was published in chemistry journal Chem, a new Chemistry journal from Cell Press by researchers from CAS Key Laboratory of Low-Carbon Conversion Science and Engineering, Shanghai Advanced Research Institute (SARI).

　　A new review article on the subject of converting CO2 and ethylene to acrylic acid and derivatives was published in chemistry journal Chem, a new Chemistry journal from Cell Press by researchers from CAS Key Laboratory of Low-Carbon Conversion Science and Engineering, Shanghai Advanced Research Institute (SARI).
　　As one of the most important classes of fine chemical products, acrylate serves as the key building block for a variety of crucial polymeric materials. As of 2013, the world capacity for acrylic acid alone was 6 million tons. Traditional manufacturing of acrylates has been done by the oxidation of propylene via a two-step sequence. In the late 1970s, chemists discovered the addition reaction between CO2 and alkene, mediated by transition-metal complexes. Since then, a large amount of time and resources have been invested in seeking an effective catalyst for this transformation, with the emphasis on the addition of CO2 and ethylene.
　　This new review summarizes critical findings in the development of this industrially relevant process and discusses mechanistic insights. The featured reaction is believed to be a perfect example for Carbon Capture and Utilization (CCU) that produces value-added chemicals, and will inspire potential solutions to other CCU transformations that involve the reduction of CO2.
　　“The conversion of CO2 and ethylene to acrylate has been a dream reaction in the realm of catalysis and carbon dioxide utilization, with tremendous efforts from scientists during the past four decades,” said WANG Xiao, adjunct professor at SARI and instructor at Harvard Medical School. “Although conventional synthesis may be largely sufficient to meet the current need, the CO2/ethylene route is definitely the state of art that spins straw into gold. Currently, the major limitations include low turnover number and harsh reaction conditions. Nevertheless, we are not to be deterred, and I strongly believe that an efficient catalytic system will eventually be realized. ”
　　

2017-08-14 more+

Researchers Find New Approach to Convert CO2 Directly into Gasoline

A paper by a joint research team was published in the leading scientific journal Nature Chemistry on June 12, 2017.The research team has found a new approach to convert carbon dioxide directly into gasoline by using a bifunctional catalyst contained a reducible oxide (In2O3) and a zeolite (HZSM-5).

　　A paper by a joint research team from CAS Key Laboratory of Low-Carbon Conversion Science and Engineering of Shanghai Advanced Research Institute (SARI) and SARI-ShanghaiTech University Joint Lab was published in the leading scientific journal Nature Chemistry on June 12, 2017.
　　The research team has found a new approach to convert carbon dioxide directly into gasoline by using a bifunctional catalyst contained a reducible oxide (In2O3) and a zeolite (HZSM-5), which will not only help to alleviate the global warming caused by increasing atmospheric CO2 concentration, but also offer a solution to replace dwindling fossil fuels.
　　“Because carbon dioxide is extremely inert, previous recycling was mainly on converting it to chemicals like methanol. But our findings are able to convert the greenhouse gas into value-added chemicals with two or more carbons like gasoline directly. And the conversion is of very high efficiency due to the newly developed catalyst.” said ZHONG Liangshu, one of the project researchers.
　　Currently, CO2-based Fischer–Tropsch synthesis (FTS) route over modified Fe-based catalysts can be used for the production of hydrocarbons. According to Anderson–Schulz–Flory distribution, however, the chain growth probability of FTS limits the proportion of desired C5–C11 hydrocarbons only with 48% at maximum of C5–C11 selectivity. In addition, the degree of hydrogenation of surface-adsorbed intermediates in CO2-based FTS is higher due to the slower adsorption rate of CO2 when compared to CO hydrogenation, leading to more readily formation of methane with a decrease in chain growth. In the present work, the bifunctional catalyst exhibits excellent performance for the direct production of long-chain hydrocarbons from CO2 hydrogenation with high selectivity. The C5+ selectivity in hydrocarbons distribution (carbon atom-based) reached up to 78.6% with only 1% CH4 at a CO2 conversion of 13.1% (Figure). There was no obvious catalyst deactivation over 150 h, and much better performance was observed with internal gas recycling. Such results suggest a promising potential for its industrial application.
　　Figure: Direct conversion of CO2 into liquid fuels with high selectivity over a bifunctional catalyst （Image by GAO Peng）
　　China is the world's biggest carbon emitter and much attention has been paid to cut emissions. Chinese President Xi Jinping made the pledge that China would peak CO2 emissions by around 2030 in his speech at the United Nations Conference on Climate Change in Paris. If CO2 can be directly and efficiently converted into liquid fuels, the dream toward cycling carbon by mimicking nature will come true. Thanks to the support from the National Natural Science Foundation of China (NSFC), the Ministry of Science and Technology (MOST), the Shanghai Science and Technology Committee (STCSM) and Chinese Academy of Sciences (CAS), the research team has published the results on direct production of lower olefins from syngas in Nature last year. The results are highlights for the integration of research and education between SARI and ShanghaiTech and have laid a solid foundation for the development of Zhangjiang Comprehensive National Science and Technology Center.

2017-06-14 more+

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+