For one whole week starting 7 PM tomorrow night (AEST) I will be tweeting from the curated twitter account @realscientists. Real Scientists is a totally awesome rotational twitter account run by totally awesome twitter people which you can find out more about here. So far there have been loads of really interesting scientists and science-related people tweeting for Real Scientists, so I have some clown-sized shoes to fill.
The account currently has in excess of 2,600 followers, which is close to a bazillion more followers than I have on my regular twitter account, @reneewebs (eep!). If, perchance, you happen to follow me but not Real Scientists, consider this your first official warning.
I think I am the first chemist to have the honour of tweeting for Real Scientists, so twittersphere – prepared to be chemified! Follow my adventures in chromatography, from the dizzying highs of a time-of-flight mass spectrometer flight tube to the chillying lows of cryogenic modulation.
See you on the twit-side!
Here we go with another of the bloggy doggy’s great Chemistry-themed carnivals, and this time it’s the #ChemMovieCarnival.
Although it’s not really chemistry-related, I’ve chosen a scene from the 2001 Richard Kelly cult classic, Donnie Darko. This is possibly my most favourite movie ever, definitely top three, and I’ll even admit to enjoying the director’s cut more than the original film.
The really short (~20 s) scene in question involves the main character Donnie (Jake Gyllenhaal) walking home from school with the new kid Gretchen (Jena Malone) and they have a conversation about an assignment Gretchen has been set by the science teacher Professor Monnitoff (Noah Wyle).
Gretchen Ross: Look, I should go. For physics, Monnitoff is having me write this essay. Greatest invention ever to benefit mankind.
Donnie Darko: It’s Monnitoff. But that’s easy. Antiseptics. Like the whole sanitation thing. Joseph Lister, 1895. Before antiseptics, there was no sanitation, especially in medicine.
Gretchen Ross: You mean soap?
Leaving aside any factual errors in Donnie’s statement, you can see from the screencap below that Gretchen has this completely incredulous look on her face, awash with teenage attitude. I think part of the reason I was so drawn to this movie initially is that the interactions between the characters are so authentic and believable against the backdrop of some out-and-out batshit craziness.
I really like this scene, and the question it poses, because although I’d largely prefer to forget the bulk of my high school years, I was lucky enough to have had one or two passionate teachers like Monnitoff (although nowhere NEAR as good looking) who would set assignments or class discussions around these kind of ‘big questions’ topics. For me, it was these types of lessons, early introductions to philosophy of science, critical thinking and the scientific method which really propelled me towards science as a career.
The importance of a strong grounding in the sciences in school is something I feel can’t be overestimated. The science teacher in this movie is an ex-academic, and the students find him approachable and knowledgeable. He is happy to take Donnie’s questions after class, and also lends him a book which plays a critical part in the plot of the movie. In another scene with Donnie and Prof Monitoff, we see the portrayal of the unfortunate position of public school science teachers in the US. Donnie is a bright and curious young man looking for guidance from a teacher, but on the question of God and religion, Monitoff is forced to end the discussion for fear of being fired. It’s unlikely that Kelly’s intention was to demonstrate the importance of an enthusiastic science teach on young minds, rather it is a by-product of his careful character development in this film.
Another ‘big question’, and one of the main themes of the film is time travel. But I’ve already not talked about chemistry in this post, so I’m certainly not going to not talk about physics as well!
The latest research article to come out of my group is now available online in the American Chemical Society journal Energy and Fuels (paywalled). The title “Oxidation of neat synthetic paraffinic kerosene fuel and fuel surrogates: quantitation of dihydrofuranones” is probably more than enough to put off any non-specialist reader, but I think it is a reasonable summation of the entire paper. So in breaking down the title, I will explain what the paper is all about.
Oxidation: The word ‘oxidation’ can be used to describe lots of different chemical reactions, and will mean different things to people even within different disciplines of chemistry. In the context of this work, oxidation refers to the reaction of the molecules in fuel with oxygen from the atmosphere, or dissolved in solution, to incorporate the oxygen into the structure of the molecules.
Fig.1 An example of one type of oxidised fuel molecule.
Fuels oxidise naturally over time, but generally get used up (burned in an engine) long before it could become a problem. However, oxidation, like most chemical reactions, happens much more quickly at high temperatures. A lot of modern aeroplane and ships are designed in such a way that the fuels are cycled through hot areas of the engine or fuel system before they get burned. This means that the fuels can become oxidised within the fuel system in a matter of minutes or hours. The oxidation reactions lead to the formation of solid deposits and gums which can damage engine parts, making it run less efficiently and require more maintenance.
Neat: ‘Neat’ is one of those weird words that means something completely different in the scientific vernacular to regular conversation. Rather than meaning ‘nifty, good, or tidy’, the scientific ‘neat’ refers to something being pure, unadulterated, or unblended.
It is quite common for fuels to be blended with other fuels or additives before use, for lots of different reasons (I will talk more about this in the next section). But the fuels that we used in this study were used ‘as is’ – unblended and more or less pure. This makes it a little easier for us to investigate, eliminating the introduction of possible unknown quantities into the fuel.
Synthetic Paraffinic Kerosene Fuel (SPK): SPK is a generic term for jet fuel which has been created from a non-crude oil source, usually via one of two processes; synthesis from carbon monoxide and hydrogen gases (Fischer-Tropsch process), or processed biological oils and fats.
- Synthetic: This really just refers to the fact that these fuels are not traditional fossil fuels, made from dead dinos and dug up out of the ground.
- Paraffinic: Paraffin is just another name for hydrocarbon, the molecules which make up fuels.
- Kerosene: Kerosene is a generic name for a mixture of hydrocarbons with characteristics which makes it suitable for use as an aviation fuel.
Fuel Surrogates: This is a term we use for mixtures that resemble a fuel in a particular way, but have been simplified in order to study them in more detail. Fuels can contain over a million different chemicals, so it’s often necessary to create ‘model fuels’ from a reduced selection of chemicals which are far less complex and easier to analyse.
In this study we’ve used two different fuel surrogates. One is a single component surrogate, one pure compound which we studied to determine if the oxidation was dependent on reaction with other molecules in the fuel. Turns out it’s not, all you need is one hydrocarbon, oxygen and heat. The other surrogate has nine components, representing the main classes of compounds found in real fuels. This was able to give us a better idea of the range of chemicals that are formed when a real fuel is oxidised.
Quantitation: Quantitation is just a fancy way of saying ‘measured with a known amount of accuracy and precision’. Generally, chemical analysis can be qualitative (what is it?), quantitative (how much is there?), or both. In this paper we have used some different techniques to try and quantify the compounds of interest
- Fourier Transform Infrared Spectroscopy (FTIR)
An FTIR instrument uses molecular vibrations to look at the different functional groups within molecules. Generally the functional groups that exist in oxidised compounds would be well suited to FTIR analysis, but in this case the complexity of the fuel mixture coupled with the very low concentrations of the compounds of interest makes it quite difficult to get accurate determinations. This is why the 2 separation techniques described below are more useful.
- High Performance Liquid Chromatography (HPLC)
A liquid chromatograph is often used for quantifying lots of different chemicals and has a huge range of applications across many industries. In this case the HPLC was used purely for its separating power, in order to facilitate quantitation with another technique (GC-MS, below). The interactions that occur between the fuel sample and the instrument allow the compounds of interest to be (mostly) separated from the fuel matrix.
- Gas Chromatography-Mass Spectrometry (GC-MS)
GC operates on the same principle as HPLC above – that is, interactions between the instrument and the sample allow for separations of mixtures to occur. Here, GC is really useful because the separations are very high quality and made even better by the rough separation already carried out by the HPLC. The coupling of a GC to another instrument (mass spectrometer, MS) increases the power even more as it allows for fast and simple identification of the molecules in the mixture.
Dihydrofuranones: Now, I’ve saved the most exciting part for last. A dihydrofuranone (or furanone for short), is a molecule which arises when a hydrocarbon becomes oxidised and eats its own tail, forming a cyclic molecule. In the example below, the yellow-coloured section could represent any hydrocarbon chain. These types of molecules have only been seen in fuels before where the oxidation temperature was much higher, or the oxidation time was much longer.
Fig. 2 Generic structure of a furanone molecule.
So what, I can hear you say, so what? There are two ‘so what’ aspects to this.
- These furanones have two oxygen atoms very close to each other, incorporated into the molecule. Normal unoxidised fuel hydrocarbons have no oxygen molecules in them. The presence of oxygen atoms in the molecule like this tends to attract water into the fuel from the atmosphere, particularly in humid environments. When water gets all friendly with the furanone molecules and becomes incorporated into the fuel, this is really bad news. Water in fuel can form ice crystals, which block the fuel system, and has been known to cause crashes. It also increases wear and corrosion, so is generally a very undesirable thing to have in your fuel and you definitely don’t want stuff in your fuel which increases the susceptibility to take up water.
- The oxidation reactions don’t stop once the furanones are formed. The fuel keeps on reacting with itself and creating new molecules which then go on to form insoluble particles and gums in the fuel. This is another way that engine blockages and wear can occur. So if we can figure out the mechanism of how the gums and particles are formed, we can work out ways to stop it happening in the first place.
So there you go, a whole scientific paper explained using only the title. The next paper I’m working on is about trying to figure out faster and more accurate ways of measuring oxidation products in fuels.
Once again, SeeArrOh has started a chemblogo/twittersphere storm with the Up-goer Five Challenge for chemists. Using the online text editor, I had a couple of goes at this, one for twitter on the hashtag #upgoer140, which is my attempt at explaining chromatography in less than 140 characters;
And then another longer version in which I try to explain my work looking at the thermal degradation of fuels;
I use a box which takes stuff that was close together and makes them not be near to each other any more. Then I can see what each of the things are, when before it was hidden from me.
Usually I use the box for looking at stuff that makes cars and other things like flying and water cars go. When the flying cars are flying, this stuff can get too hot and then new stuff is formed, which can be bad and make the flying cars stop flying.
I use the box to look at the new stuff that is formed when it gets hot to try and find out things about the new stuff. I want to know what it is, where it came from and how to make it stop happening.
It’s actually pretty hard, but quite fun too. I recommend giving it a go.
Because we can just never get enough chemophobia, See Arr Oh from the Just Like Cooking blog has alerted the chemblogosphere to some more ridiculous scaremongering about the chemicals in our food. He has rightfully ridiculed the advertising and you should go there and read it (and about what the pseudonymous dog has for breakfast himself!).
However, the post made remember something I did ages ago (maybe 6-7 years?) which I had completely forgot about and I will share with you below:
The biscuits made from this recipe actually won me a baking competition at the place I worked at the time. Although of course they were tremendously delicious, I attribute my win to the fact that I displayed this recipe along with the cookies, and the judges all had chemistry degrees. A lesson in knowing your audience
Reader @markemer has pointed out that vanilla essence (reagent #7) is not pure vanillin, and usually is a solution containing a number of other compounds, including water, ethanol, and methyl carbinol. Thanks Mark, corrections always welcome.
Following on from my last post, I decided to email Baccarat, the company selling the ‘chemical free’ cookware range, Bio+. My email is reproduced below. I tried my darnedest not to be snarky, but I fear I am a self-confessed, born smart-alec and I find it impossible to fully suppress.
I recently came across some advertising for the new Baccarat cookware range named Bio+, and there were a couple of things about the product marketing that I found a little confusing.
1. The products are marketed as ‘chemical free’.
I recall from my primary school science classes that all matter in the universe is made from chemicals. I’m fairly certain that the materials that your cookware is made from are also chemicals (perhaps iron or aluminium, carbon, oxygen, hydrogen and others). If what you are trying to say is that the cookware is free of Teflon or other fluorinated molecules, I think it would be more appropriate, and importantly, more accurate, to say this instead. To claim the products are ‘chemical free’, is simply untrue and chemophobic.
2. The use of the prefix ‘Bio’.
I am curious as to the reasoning behind the use of ‘bio’ in the product name. Is there anything in particular about the manufacture of the cookware that is biological? Perhaps biologically (plant, algal) derived source materials? Biorefined metals? I do hope that there is a basis for using this prefix and would be very interested to know what it is, and that it is not just greenwashing.
Thank you for reading and I look forward to your reply.
And the reply I received today:
Good Morning Renee,
Thank you for your enquiry.
I believe you would be referring to matter being a chemical element is a pure chemical substance consisting of one type of atom distinguished by its atomic number, which is the number of protons in its nucleus. This is different from this, which is a natural occurrence, and the traditionally used term ‘chemical’ which is a compound or substance that has been purified or prepared, esp. artificially.
The Bio+ range is simply a name that was chosen for this range due to its chemical free ceramic interior (PFOA and PTFE free), making it a healthier choice. Ceramic coatings are environment friendly, pollution free. The body provides effective and even heat distribution reducing cooking times and saving energy fuel. Non stick, easy clean and chemical free.
I would like to take this time to thank you for your comments, I have passed them on for review.
The person who replied to me has helpfully provided a number of Wikipedia links, to help me understand what constitutes an atom. Of course, they weren’t to know that I have a reasonable grasp of this area, mainly thanks to my double major in chemistry which funnily enough, did actually go over this stuff a little bit.
I will have to concede that this person has a basis for saying that the colloquial meaning of ‘chemical’ is generally something which has been processed or refined in some manner, and I guess I wasn’t clear enough in my email in trying to get across my point that *everything* is made from chemicals. This is really the crux of the problem; even though they have (I hope) thought a little bit about what I wrote in my email, and at least looked at some pertinent Wikipedia entries, the false delineation of natural=good=element/artificial=bad=chemical, still stands in their mind.
The second point was, I feel, addressed in a more flippant manner. It seems that the use of ‘Bio’ in the product name is indeed greenwashing, and they may have been better off using ‘enviro’ or something like that. Their claim that ceramic coatings are more environmentally friendly seems plausible to me, and I think the argument could be made that their manufacture is less energy and resource intensive (although definitely not ‘pollution free’ as they claim) than that of fluoropolymers. Although my knowledge in the area is really limited, and I would be happy if an industrial chemist could correct me.
It’s not all bad though, I am very grateful that someone took the time to respond to my query and I am really glad that my comments have been ‘passed on for review’ (I can only take it in good faith that they have been). The fight against chemophobia goes on!
On a recent stroll down a shopping strip while I was away from home for a conference, I came across this startling advertisement:
You can imagine my shock and amazement that the cookware company Baccarat had not only come up with a chemical-free ceramic material, but then also managed to construct a frying pan from it. I quite enjoy cooking, and tend to covet expensive and unnecessary kitchenware items, however I’m not sure this one will be making it on to my post-Christmas sale shopping list this year seeing as I can only assume is made primarily from photons, and I already have plenty of those lying around.
Curiously, the Bio+ range seems to be absent from the Baccarat website, but several online retailers are flogging these frying pans and offer a little more insight into what they are actually trying to say when they claim the ’chemical free’ label. The use of the prefix ‘Bio’ is total greenwashing, because there is absolutely nothing about the use or manufacture of these items that is in any way biological. These frying pans, like many others, are actually made of aluminium (an element and chemical, gasp!), with a Bakelite handle (a polymer resin made primarily from the chemicals phenol and formaldehyde*) and a ceramic (usually a crystalline oxide, made from… you guessed it – chemicals!) cooking surface. What they are actually trying to get at when they say ‘chemical free’, is that these pans are not coated with PTFE (Teflon), the fluorinated polymer we associate with non-stick cooking surfaces. Whilst there have been concerns about the safety of these products, if you follow the manufacturer’s instructions in terms of the temperature you use them at, and use an exhaust fan or rangehood while you’re cooking, then they don’t pose a health risk. There are plenty of Teflon-free cookware items available on the market if you prefer not to use them for whatever reason. Most chefs don’t use Teflon pans, and instead favour cookware made from cast iron, stainless steel, copper and aluminium. The reasons being that these materials develop a better fond when cooking, are more hard-wearing for increased longevity, tolerate much higher temperatures and can be used with metal utensils.
As a side note, I also found it a quite hilarious coincidence (or maybe not), that celebrity chef Pete Evans of ‘activated almonds and alkalised water’ fame, is one of the faces of Baccarat cookware. Clearly, a man who thinks water containing vinegar is alkaline has much to learn about basic (pun intended), primary school level chemistry and is an excellent choice for ambassador of this company.
*phenol and formaldehyde are two chemicals that you certainly want to take care with on their own, in my laboratory these are both stored in special poison/carcinogen cabinets. However, once incorporated into the Bakelite resin they have reacted together to form a new, non-hazardous chemical structure and are effectively permanently trapped in that form within the resin.