Carbon Chemist

Tag: Methane

  • COP29: Satellites spot methane leaks – but ‘super-emitters’ don’t fix them

    COP29: Satellites spot methane leaks – but ‘super-emitters’ don’t fix them

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    A methane plume at least 4.8 kilometres long billows into the atmosphere south of Tehran, Iran

    NASA/JPL-Caltech

    The world has more ways than ever to spot the invisible methane emissions responsible for a third of global warming so far. But according to a report released at the COP29 climate summit, methane “super-emitters” rarely take action when alerted that they are leaking large amounts of the potent greenhouse gas.

    “We’re not seeing the transparency and the sense of urgency that we require,” says Manfredi Caltagirone, director of the United Nations Environment Programme’s International Methane Emissions Observatory, which recently launched a system that uses satellite data to alert methane emitters about leaks.

    Methane is the second most important greenhouse gas to address, behind carbon dioxide, and a rising number of countries have promised to slash methane emissions in order to avoid near-term warming. At last year’s COP28 climate summit, many of the world’s largest oil and gas companies also pledged to “eliminate” methane emissions from their operations.

    Today, a growing number of satellites are beginning to detect methane leaks from the biggest sources of such emissions: oil and gas infrastructure, coal mines, landfill and agriculture. That data is critical to holding emitters to account, says Mark Brownstein at the Environmental Defense Fund, an environmental advocacy group that recently launched its own methane-sensing satellite. “But data by itself doesn’t solve the problem,” he says.

    The first year of the UN methane alert system illustrates the yawning gap between data and action. Over the past year, the programme issued 1225 alerts to governments and companies when it identified plumes of methane from oil and gas infrastructure large enough to be detected from space. It now reports that emitters only took steps to control those leaks 15 times, a response rate of about 1 per cent.

    There are a number of possible reasons for this, says Caltagirone. Emitters might lack technical or financial resources and some sources of methane can be difficult to cut off, although emissions from oil and gas infrastructure are widely seen to be the easiest to deal with. “It’s plumbing. It’s not rocket science,” he says.

    Another explanation might be that emitters are still getting used to the new alert system. However, other methane monitors have reported a similar lack of response. “Our success rate is not much better,” says Jean-Francois Gauthier at GHGSat, a Canadian company that has issued similar satellite alerts for years. “It’s on the order of 2 or 3 per cent.”

    Methane super-emitter plumes detected in 2021

    ESA/SRON

    There have been some successes. For instance, the UN issued several alerts this year to the Algerian government about a methane source that had been continuously leaking since at least 1999, with a global warming effect equivalent to half a million cars driven for a year. By October, satellite data showed it had disappeared.

    But the overall picture suggests monitoring isn’t yet translating into emission reductions. “Simply showing methane plumes is not enough to generate action,” says Rob Jackson at Stanford University in California. A core problem he sees is that satellites rarely reveal who owns the leaky pipeline or the methane-emitting well, making accountability difficult.

    Methane is a major topic of discussion at the COP29 meeting, now under way in Baku, Azerbaijan. A summit this week on “non-CO2 greenhouse gases”, convened by the US and China, saw countries announce several actions on methane emissions. They include a fee on methane in the US, which is aimed at oil and gas emitters – although many expect the incoming Trump administration to undo that rule.

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  • Rising methane emissions from wetlands may undermine climate targets

    Rising methane emissions from wetlands may undermine climate targets

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    Countries are starting to take steps to cut human sources of methane emissions, but climate change is increasing emissions of the potent greenhouse gas from wetlands

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  • New Catalysts Turn the Greenhouse Gas Methane Into Valuable Chemicals

    New Catalysts Turn the Greenhouse Gas Methane Into Valuable Chemicals

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    Methane or Ammonium Molecules

    In a recent study, researchers from the Tokyo Institute of Technology developed a new bifunctional zeolite catalyst that efficiently converts methane and nitrous oxide into valuable chemicals, offering a more sustainable and energy-efficient method than traditional processes. The catalyst’s unique ability to optimize the spatial distribution of Cu and acid sites enables it to effectively reduce greenhouse gas emissions while producing useful hydrocarbons, potentially guiding future decarbonization efforts in the chemical industry.

    Researchers developed a novel catalyst that converts methane into valuable chemicals more sustainably, potentially advancing efforts to decarbonize the chemical industry.

    Methane, a potent greenhouse gas, plays a crucial role both as an energy source and a vital chemical feedstock. Typically, methane undergoes conversion into methanol before being transformed into hydrocarbons. This process, however, demands elaborate industrial systems. Crucially, because methane is a highly stable molecule, converting it into methanol through traditional methods like steam methane reforming is highly energy-intensive.

    Against this backdrop, the catalytic conversion of methane into methanol or other chemicals has attracted much attention from scientists, who are eager to find more energy-efficient and sustainable solutions. Among recently reported catalysts, copper (Cu)-containing zeolites have shown promise for methane-to-methanol conversion at mild conditions. Unfortunately, the yield and selectivity of most reported catalysts have been low, meaning that large quantities of undesirable byproducts are generated alongside methanol.

    New Insights on Bifunctional Catalysts for Tandem Methane Conversion

    This study provides new ways to turn methane and nitrous oxide into value-added substances, contributing to the decarbonization of the chemical industry. Credit: Tokyo Tech

    In a recent study published in Nature Communications, a research team including Associate Professor Toshiyuki Yokoi from Tokyo Institute of Technology, Japan, investigated a new type of bifunctional zeolite catalyst. Interestingly, this Cu-containing, aluminosilicate-based zeolite is capable of converting methane and nitrous oxide, another greenhouse gas, directly into valuable compounds through a series of intermediate reactions.

    Optimizing Catalyst Structure for Enhanced Output

    One of the key questions the researchers addressed was how the spatial distribution of different active sites in the catalyst affected the output of the reactions. To this end, they prepared multiple catalysts using not only different concentrations of Cu and acid sites (proton) in aqueous solutions but also different physical mixing techniques for solid samples.

    Through various experimental and analytical techniques, the researchers found that the proximity between Cu and acid sites was crucial for determining the final products. More specifically, they reported that when Cu sites were near each other, the methanol produced in Cu sites from methane had a higher probability of being overoxidized by an adjacent Cu site, turning it into carbon dioxide. In contrast, when Cu sites and acid sites were close to each other, methanol reacted with nitrous oxide in an adjacent acid site instead to produce valuable hydrocarbons and harmless nitrogen gas.

    “We concluded that, for stable and efficient production of methanol and ultimately useful hydrocarbons from methane, it is necessary to uniformly distribute Cu sites and acid sites and have them be at an appropriate distance from each other,” explains Yokoi. “We also found that the distribution of products obtained is also influenced by the acid properties and pore structure of the zeolite catalyst.”

    One of the most notable advantages of the proposed catalyst is its ability to sustain tandem reactions, that is, a simple process that merges multiple steps into one and gets rid of two different harmful greenhouse gases simultaneously. This property will be key to making such catalytic systems attractive in an industrial setting. “Our work will hopefully guide future efforts to achieve methane oxidation to methanol and open avenues for promoting hydrocarbon synthesis using methanol as an intermediate,” concludes Yokoi.

    With any luck, this study will serve as a stepping stone toward the decarbonization of the chemical industry, contributing to the realization of a carbon-neutral society.

    Reference: “Understanding the effect of spatially separated Cu and acid sites in zeolite catalysts on oxidation of methane” by Peipei Xiao, Yong Wang, Lizhuo Wang, Hiroto Toyoda, Kengo Nakamura, Samya Bekhti, Yao Lu, Jun Huang, Hermann Gies and Toshiyuki Yokoi, 28 March 2024, Nature Communications.
    DOI: 10.1038/s41467-024-46924-2

    The study was funded by the Japan Society for the Promotion of Science.



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  • Electro-Fenton Magic Makes Methane the New Eco Fuel Hero

    Electro-Fenton Magic Makes Methane the New Eco Fuel Hero

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    Electrochemical Conversion of CH4 and O2 to HCOOH

    Researchers realize electrochemical conversion of CH4 and O2 to HCOOH at room temperature. Credit: JACS

    A team from the Dalian Institute of Chemical Physics made a breakthrough in converting methane to formic acid using oxygen at room temperature through a high-pressure electro-Fenton process, achieving significantly higher efficiency and productivity than traditional methods.

    Direct conversion of methane (CH4) and oxygen (O2) to value-added chemicals is important for natural gas industries. However, challenges remain due to the difficulty of O2 activation in forming active oxygen species for CH4 activation under mild conditions.

    Recently, a research group led by Prof. Dehui Deng, Assoc. Prof. Xiaoju Cui and Liang Yu from the Dalian Institute of Chemical Physics (DICP) of the Chinese Academy of Sciences (CAS) realized the electrochemical conversion of CH4 by O2 to formic acid (HCOOH) at room temperature. This study was published in the Journal of the American Chemical Society.

    The researchers developed a high-pressure electro-Fenton strategy to establish a hetero-homogeneous process for electro-catalytic conversion of CH4 by O2 at room temperature. They revealed that CH4 was efficiently activated by ·OH, which was produced via a heterogeneous electroreduction of O2 to H2O2 on the Ag foil cathode, followed by a homogeneous Fe2+-facilitated H2O2 decomposition.

    Besides, the researchers found that the elevated pressure not only improved the productivity of H2O2 from O2 electro-reduction but also boosted the reaction collision probability between CH4 and active ·OH in-situ generated from Fe2+-facilitated decomposition of H2O2.

    Compared with the traditional electro-catalytic CH4 conversion process with high overpotential (>0.9 V) and low Faradaic efficiency (< 60%), the high-pressure electro-Fenton process achieved an HCOOH Faradaic efficiency of 81.4% with an ultra-low cathodic overpotential of 0.38 V. The HCOOH productivity was 11.5 mmol h-1 gFe-1, which was 220 times that of ambient pressure.

    “This work provides a new way for energy-efficient and sustainable conversion of CH4 by directly using O2 under mild conditions,” said Prof. Deng.

    Reference: “High-Pressure Electro-Fenton Driving CH4 Conversion by O2 at Room Temperature” by Yao Song, Xiao Yang, Huan Liu, Suxia Liang, Yafeng Cai, Wenqiang Yang, Kaixin Zhu, Liang Yu, Xiaoju Cui and Dehui Deng, 26 January 2024, Journal of the American Chemical Society.
    DOI: 10.1021/jacs.3c10825



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  • Methane leaks from US oil and gas are triple government estimates

    Methane leaks from US oil and gas are triple government estimates

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    A methane plume detected by NASA's AVIRIS-NG in summer 2020 indicates a leaking gas line in oil field in California

    A methane plume in California detected by an airborne spectrometer

    NASA/JPL-Caltech

    Major oil and gas-producing regions in the US are leaking much more methane than current estimates suggest, according to nearly a million aerial measurements of the potent greenhouse gas.

    “Our study used the largest such dataset that’s ever been assembled,” says Evan Sherwin at Lawrence Berkeley National Laboratory in California, who conducted the research while at Stanford University.

    He and his colleagues combined data from numerous aerial surveys that used infrared sensors to measure methane leaking from wells, pipelines…

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  • Satellite launched to track down leaks of potent greenhouse gas

    Satellite launched to track down leaks of potent greenhouse gas

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    methaneSAT

    An artist’s impression of MethaneSAT

    Environmental Defense Fund/NASA

    A satellite expected to transform our view of planet-warming methane emissions from oil and gas production has launched from the Vandenburg Space Force Base in California. Called MethaneSAT, the satellite will orbit the planet 15 times per day, using infrared sensors to measure methane leaking from all of the world’s major production centres.

    “We designed MethaneSAT explicitly to serve one goal,” says Steven Hamburg at the Environmental Defense Fund (EDF), the non-profit advocacy group that developed the satellite along with a consortium of universities and aerospace firms. “To produce policy-relevant data to track methane emissions from the oil and gas industry, globally.”

    Methane is the most significant greenhouse gas behind carbon dioxide. And oil, gas and coal production are among the largest sources of anthropogenic methane emissions. Many governments have set targets to slash methane emissions by 30 per cent by 2030, and at the COP28 climate summit last year, a number of large oil and gas companies pledged to zero out all methane emissions from their operations by 2050.

    But assessing progress towards those pledges is difficult. Current methane emissions remain poorly quantified, leaks are challenging to track and aerial surveys and on-the-ground monitoring are expensive – and some countries don’t allow them. MethaneSAT joins a growing constellation of methane-sensing instruments in orbit aiming to provide a better view. Existing satellites, like the European Space Agency’s TROPOMI, sense methane emissions across large regions. Others, like the 11 methane-sensing instruments run by Canadian company GHGSat, focus on identifying specific point sources of methane.

    In contrast, MethaneSAT will regularly monitor methane at high resolution in between these scales, enabling researchers to quantify emissions across the areas relevant to oil and gas production as well as map their probable sources. “We needed to be able to see all the emissions and resolve them in space,” says Hamburg.

    Once running full bore, the satellite will deliver up to 30 different 40,000 square kilometre “scenes” of measured methane flux per day, according to Hamburg. He says they will prioritise monitoring oil and gas production regions – such as the Permian basin in west Texas – but will also be able to measure methane from other major sources like agriculture, wetlands and landfills. “Methane is methane,” he says.

    Along with developing the satellite, Hamburg and his colleagues have produced a pipeline to rapidly turn the raw data it generates into publicly available estimates of the amount of methane emissions, and the probable sources of plumes. This includes a global database of oil and gas infrastructure created in partnership with Google to help link detections of methane with their sources.

    “We’re mapping the whole thing,” says Hamburg. He says the satellite will generate more data on methane emissions from oil and gas in its first year of operation than was collected over the past 50 years. Full data collection is expected to begin in early 2025.

    “The data is here, and the technology is here to start taking action,” says Jean-Francois Gauthier at GHGSat, who expects MethaneSAT will help identify sources of emissions that GHGSat’s focused satellites can then measure in more detail.

    Rob Jackson at Stanford University in California says the satellite will provide an independent check on emissions reported by companies and countries. “There will be nowhere to hide,” he says. The flood of data could also help explain the still-uncertain source of rising rates of methane since 2007, he adds.

    “The big question for me is how people will use the information,” says Jackson. “There’s an assumption out there that once we have all the information the emissions will go away somehow. But having information from aircraft and on-the-ground sources has not stopped those emissions.”

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  • Sunlight to Syngas: Revolutionizing Methane Reforming

    Sunlight to Syngas: Revolutionizing Methane Reforming

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    Energy Fuel Gas Production Concept Art

    Scientists have developed a novel photocatalyst system for efficient syngas production from methane steam reforming, using solar energy and operating under atmospheric pressure. This technology marks a significant step towards sustainable syngas production and a post-carbon energy future. Credit: SciTechDaily.com

    A new solar-driven photocatalysis method for syngas production from methane steam reforming promises a more sustainable and efficient approach to syngas generation.

    Recent research reveals a breakthrough in solar-driven syngas production, marking a potential transition to a post-carbon energy era. This innovative process involves the reforming of methane steam, a method that heats methane with steam in the presence of a catalyst to generate hydrogen and carbon monoxide, collectively known as syngas. Syngas is a valuable resource, serving as a versatile fuel.

    Challenges in Methane Steam Reforming

    Historically, achieving the necessary chemical reactions for methane steam reforming has been challenging. The process typically demands high temperatures between 700 and 1000 degrees Celsius and pressures exceeding 20 bar. These demanding conditions have limited its practicality and efficiency.

    Syngas Photocatalysis Made Easy

    Schematic for simultaneous adsorption/activation of CH4 and H2O by RhOx/GaN system based on density functional theory calculations. Credit: Li et al.

    Photocatalysis: A Novel Approach

    Baowen Zhou and his team introduce a pioneering photocatalysis platform that enables syngas production in a quartz chamber under atmospheric pressure illuminated by a 300 W Xenon lamp without any other energy inputs. The core of this technology is based on group III nitride nanowires enhanced with rhodium nanoclusters.

    Mechanism of the Photocatalytic Process

    Detailed theoretical calculations, microscopic examinations, and in situ spectroscopic measurements have demonstrated that the RhOx/GaN@InGaN nanowires are capable of activating both methane and water molecules under light exposure. Just add light, and methane is split into methyl anions and hydrogen species, while water is split into hydrogen species and hydroxide. Subsequent reactions, facilitated by rhodium and gallium nitride, lead to the formation of syngas.

    Efficiency and Stability of the New System

    The effectiveness of this new method is evident, with a production rate of 8.1 mol syngas per gram of hydrogen and 10493 mol syngas per mol rhodium oxides observed over a 300-minute stability test. This represents a significant advancement in syngas production technology.

    Reference: “A semiconducting hybrid of RhOx/GaN@InGaN for simultaneous activation of methane and water toward syngas by photocatalysis” by Dongke Li, Zewen Wu, Yixin Li, Xiaoxing Fan, S M Najib Hasan, Shamsul Arafin, Md Afjalur Rahman, Jinglin Li, Zhouzhou Wang, Tianqi Yu, Xianghua Kong, Lei Zhu, Sharif Md Sadaf and Baowen Zhou, 21 November 2023, PNAS Nexus.
    DOI: 10.1093/pnasnexus/pgad347



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