In this little write-up, I am questioning the largely misleading press coverage of a cell.com article by some MIT authors quoted below, which reports the production of hydrogen from seawater using elemental aluminium activated with some rare metals, which we are going to ignore (The rare metals, I mean). In all fairness, the title of the paper itself talks about the enhanced recovery of exactly those rare activation metals. But the press department of MIT already converted that into a revolutionary method to produce hydrogen from seawater.
Part of problem why popular press might misunderstand things is of course that they never read the primary article but just cite that press department statement. But in this case, the way the original authors talk about energy efficiency in their paper is also a problem. They write: “Estimations indicate that the energy inputs required for various subprocesses involved in treating aluminum for fuel production constitute approximately 2% of the total energy output from the reaction.” This is of course only true if you think that aluminium lies around on the street in elemental form, which indeed it does in the form of thrown away soda cans, which, as we all know, grow on soda can trees.
But here are some basics to reconsider what has been reported. Those “basics” are a result of some afternoon of googling and back-of-the-envelope calculations. There might be a major flaw and I am happy to stand corrected.
Aluminum is produced from bauxite using the Bayer Process. It is one of the most energy-intensive industrial processes on the planet.
55% of all aluminium is produced with coal as an energy source, 10% from gas, the rest is hydropower and other renewables..
The production of 1 Kg of Aluminum from bauxite needs at least 13 kWh electrical energy.
The energy density of 1 Kg of H2 is 33 kWh.
The atomic weight of Al is 13, the molecular weight of H2 is 2.
Here is the chemical equation of the reaction of elemental aluminium with water to produce hydrogen:
2 Al + 3 H2O -> Al2O3 + 3 H2
This means that 26 kg of aluminium produces 6 kg of hydrogen. In energetic terms, 338 kWh is needed to produce roughly 200 kWh worth of energy in the hydrogen synthesised, an efficiency of approximately 60%!
Conventional electrolysis systems that produce hydrogen from water have an efficiency of 60% – 85%. But then of course you need to compress, transport, etc, the H2.
If you recycle the aluminium, only 5% of the energy from the Bauxite process is needed – a far better energy efficiency than when burning (oxidising it to Al2O3 again) it.
This might all be fine. The aluminium could be produced using completely from renewable energy. Then the authors’ argument that “aluminum holds twice the energy density per unit volume of diesel and approximately 40 times that of lithium-ion batteries.” might be relevant.
Currently, a large amount of fossil energy would be invested to produce hydrogen with a moderate efficiency of 60%, which is then used to propel ships, presumably with a fuel cell with an efficiency of again 60%. This is clearly not what the authors of the many press items about this paper have understood and conveyed in their articles.
I have been working, very sporadically but for quite a while, on an ESP8266-based room climate logger with an BME280 sensor.
This sensor measures temperature, humidity and atmospheric pressure.
My current setup uses a Wemos D1 mini plus a Wemos battery shield as well as Waveshare 1.5 inch e-paper display. The display is updated once per minute and the data is logged to ThingSpeak at the same rate.
I had tremendous fun this weekend after my first 3D printer, a Wanhao Duplicator i3+ arrived.
The reason for getting a 3D printer was even more fun I am recently having with microcontrollers, especially the ESP8266, and I needed a way to printer perfectly fitting enclosures for my builds. Stay tuned for details.
My brand new WanHao i3+ 3D printer
Regarding the 3D printer, I originally wanted to go for an Anet A8 and then follow the upgrade instructions from Heise published in my favourite computer magazine more than a year ago, but then found the advice to circumvent all the hassle and buy the Wanhao or one of the many similar designs. The price is comparable to where you end up when you upgrade an A8. And I think the advice was correct. It took me 15 min to assemble the Wanhao i3+ and to get the first prints done. Within half a weekend, I had printed a filament guide, a case for the Raspberry Pi camera which mounts to the i3+ print bed and hooked the whole thing to a Raspberry Pi running the OctoPi operating system with OctoPrint. Of course PuTTY SSH session timeout , the Raspberry Pi will be in a printed case. As you can see from those links, none of the models that I printed this weekend were designed by myself. They are all downloaded from Thingiverse.com – an absolutely fantastic resource of 3D models, which were made available by makers around the planet.
We are thrilled to announce that the proposal “Balance of the Microverse” has been selected as a cluster of excellence by the Excellence Commission, consisting of the members of the international Committee of Experts and the research ministers of the federal and state governments of Germany. Group leader Prof. Christoph Steinbeck is one of the principle investigators of the proposal. The cluster will be funded with 50 mio Euros over 7 years. The mission of the Balance of the Microverse Cluster is to understand microbial balance from the molecular to the ecosystem level and to develop detection and manipulation technologies to create beneficial impact.
NMR spectroscopic data is a cornerstone in the structure elucidation and identification of organic molecules. In publications on newly synthesised compounds and their intermediates as well as in the characterisation of novel natural products, NMR data are indispensable components of experimental sections, albeit typically reported in ways which destroy information. This talk reports on two current community efforts to a) create an open, distributed and internationally adopted repository for raw NMR data (McAlpine2018) and b) the new NMReData format, a lightweight description of curated NMR data and their assignment to chemical structures (Pupier2018).
Raw NMR data only reaches its maximum potential usefulness if it is universally accessible. While molecular biology has paved the way through the establishment of open data repositories in many of its subfields, developments in areas overlapping with chemistry, such as metabolomics, have shown that the technology for a repository for open raw NMR data is at our fingertips and we will discuss aspects leading towards the creation of such an archive. Furthermore, here is no standard file for the NMR data relevant to structure elucidation. With NMReData, a file format is introduced and presented here, to associate the NMR parameters extracted from 1D and 2D spectra of organic compounds with the assigned chemical structure. NMReDATA descriptions include chemical shift values, signal integrals, intensities, multiplicities, scalar coupling constants, lists of 2D correlations, relaxation times and diffusion rates. This format is easily readable by humans and computers and provides a simple and efficient way for disseminating results of structural chemistry investigations, automating the verification of published result, and for assisting the constitution of open-access structural databases.
We believe that the combination of these two grassroots movements as well as a requirement from publishers to deposit the raw NMR data in open access repositories, as is customary and well accepted in genetics, crystallography and other fields, will have a substantial impact on the reproducibility of chemistry studies and aid the development of new and better tools for dereplication and structure verification.
Honoured to co-author the just-appeared piece on the value of universally available raw NMR data for transparency, reproducibility, and integrity in natural product research: https://dx.doi.org/10.1039/C7NP00064B
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