Science in my pocket.

It seems that I can be fairly accused of not keeping up with what's going on out there. A few months ago, I posted on the slowly developing trend to taking advantage of the advantages that smart mobile phones offered in being able to be used as highly portable scientific instruments. Recently, a friend alerted me to a Kickstarter funding project which is set to take this concept to a much higher level. An Israeli company called Consumer Physics has been working away on a miniature NIR (Near Infra Red) analyzer for the past couple of years, and has targeted the beginning of 2015 for release of their SCIO instrument. 

The ultimate idea is that you would point it at an object, and it will give you its chemical analysis. Of course, nothing in life is easy, and NIR is no exception. NIR has been around for decades, but the availability of cheap, powerful computers to run the software to process the complex signals coming from NIR instrumentation (and thereby yield useful results) has increased popularity in recent years. 

When NIR light is directed at an object, chemical components of that object reflect or absorb various wavelengths of that light in varying amounts. That reflected light comprises a spectrum, which is analyzed by a spectrometer contained in the handpiece. The signal from the spectrometer is sent via Bluetooth to the smart phone, where the software compares the spectrum to those analyzed previously from similar samples for which the chemical analysis is known. The accuracy of NIR analysis is dependent on a number of factors which include:

- the accuracy of the chemical analysis of the components contained in the calibration samples

- the condition of the calibration samples (how they were prepared and presented for NIR analysis)

- the similarity of the samples under test to those used for the calibration

- the condition and similarity of the surface of the object, compared to those used for the calibration

- sophistication and relevance of the algorithms used to deconstruct and quantify the spectra.

So the SCIO NIR instrument doesn't yet rival the "Tricorder" used to analyze absolutely everything in Star Trek episodes, but if the project is realized as conceived by the developer, it will (in my opinion) represent the greatest advance to date in the development of portable chemical analyzers.

Aside from the brilliance in condensing a laboratory-sized instrument to a device seeming no larger than modern electronic car "keys", to me, the stand out features are the complete liberation of the sensor and the inspired use of the Cloud to refine computation algorithms as new data is logged. No longer is the sensor attached to the signal conversion and display device by a restricting cable. It is now truly and completely wireless. Every dedicated analyzer with a sensor bound to it by a length of cable is now obsolete.

As I've said before, exciting times ahead!

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Smart pHone?

I got my iPhone 4 over three years ago. Yes, I know, by today's standards it's ancient, but I come from a generation which was taught to use things up and wear them out - it's still working nicely. I realized shortly after getting it I had a computer in my pocket, and since then I have been looking for sensors, adaptors and apps which could turn my phone into a portable scientific instrument.

With built-in location services and a clock, the time and place of the measurement can be absolutely pinpointed, and transmitted by email or SMS to remote locations. A photo of the measurement location can also be taken and transmitted. Just the thing for the roving chemist.

The trouble is, until fairly recently, there's been nothing available on offer. There are lots of handy apps for the analytical chemist, and I've got them on my phone. Periodic tables, molecular mass calculators, and regression analysis calculators for preparing calibration curves. They're good and they're handy, and they've come to my rescue when I've been at a customer's and couldn't boot up my notebook to the internet, but somehow, I felt a lack....of, well, something better...until I found the Sensorex PH-1 pH meter for Apple mobile products a couple of years ago. It was cool, and I had to have one. It plugs into the connector of my iPhone, and a pH probe with a BNC connector plugs into it. The software is free from iTunes, and it all works very nicely. There's multi-point calibration, and you can save the calibration. You can email the readings, and you can name the location of your reading either however you like or with its GPS location.

So it all works very nicely. There's a couple of  problems chief of which is the fact that the iPhone 5 and later models use a different connector. That is easily solved with an adaptor, but you'll need a Lightning > 18-pin adaptor. However, I'm still very happy with this little device.
It seems that Sensorex have now resolved this problem with their new SAM-1 Smart Aqua Meter, which now connects to smartphones (Apple and Android devices) through the headphone socket. The new meter also performs conductivity and ORP measurements as well. Reportedly, shipments start mid-March 2014 on this product. Another thing that I like is that you can buy online, and that PayPal is accepted as payment.

I note that Sensorex are promoting their "smart" probes, which are auto-recognized by the SAM-1. Great, but they're probably not the first in this area. Way back in 2000, our Multitrator thermometric titration system went to market with our Intelligent Probe thermometric sensors. The probes contained a chip which stored the probe's manufacturing data as well as the calibration data which converted mV to temperature. There was also the capability for storing your own calibration data if you wanted to do some really accurate enthalpimetric measurements.

There is a remaining niggle with the SAM-1. You still have to connect a probe directly to the meter. Wouldn't it be nice if you could be free of those tangly, interference-prone analog wire connections, and make your pH, conductivity, ORP (and maybe even ISE) measurements wirelessly and digitally?
It seems that there are moves in this direction. A company called Sensorcon has brought out a multi-sensor device called Sensordrone, which connects via Bluetooth to Android devices. 

Out of the box, it does all sorts of things ....

... and you can buy add-ons, such as a pH measurement module ....

as well as a dissolved oxygen sensor extension. The makers are promoting as a platform for third-party hardware devices. 

I can see interesting days ahead in the smartphone/portable lab. area. It's always fun to see what the future brings.

A salty tale ....

Way back in 2007, I wrote a piece on a simple chemical reaction which is now proving to be highly useful in chemical analysis for process and quality control. To save you having to scroll down to the bottom of the blog, here it is again:

You can use this reaction to determine by thermometric endpoint titration (TET) sodium, aluminium and fluoride (but not potassium), because the reaction is exothermic. I'm going to stick my neck out here, and say that this reaction offers the first viable titration method for analyzing sodium. Sure, there's been others, but none have proven to be successful. A titration based on the insolubility of zinc uranyl acetate has been around since 1931, and a complexometric procedure was reported in 1970, but my argument is that if they were of any real practical use, you would in fact see them being used. You don't. And yet titration is a great technique for routine process and quality control. Automated titration instruments don't take up much bench space, infrastructure is minimal, and lower-skilled operators can be used, providing they are well trained and well supervised.

In the case of TET, frequently it is unnecessary to filter sample solutions prior to titration. Further, the sensor is really just a fast-responding electronic thermometer. The probe doesn't need calibrating and requires little maintenance, the titrations take place in regular vessels (no insulation required), you don't need a reference electrode, the probe is always 24/7 ready - what could be easier? 

Thermoprobe thermometric titration sensor

"But wait a minute", I hear you say, "we're already titrating for sodium in food - we use silver nitrate as the titrant. That's all we need to do, isn't it?"

Well, no. It isn't good enough any more. The silver nitrate titration assumes that all sodium present is in the form of sodium chloride, common salt. You actually titrate chloride (and other halides) with the silver nitrate, and assume that all chloride is present as sodium chloride. The trouble is, that not all sodium in food comes from added sodium chloride. Lots of other sodium salts are added to processed foods; some are preservatives, some are flavour enhancers, and then there's emulsifiers and also stabilizers; all sorts of different sodium salts are used in foods. There's something else to consider: some manufacturers are seeking to reduce the sodium content of the food, while minimizing the impact of the "saltiness" of the food. They're doing this by substituting potassium chloride for some of the sodium chloride that's normally added. Look at this label from a container of margarine:
Potassium chloride is also being used as a sodium chloride replacement in snack foods as well. Check for the food code E508 on the label, if potassium chloride isn't mentioned by name.

The titration itself is quite straightforward. However, as in every analysis involving food, you have to pay attention to the sample preparation. The main aims are to liberate all the sodium from the food matrix, and to obtain a solution that is suitable for titration - not too viscous, and no lumps. Fortunately, you don't have to worry about turbidity or fine particulates, because there's no sensitive sensor membrane to foul or reference junction to clog. Even fatty foods can be handled with the appropriate sample preparattion. When you're considering the determination of sodium by TET in a food for the first time, there is a need to think carefully about the sample preparation options you need to consider.

Recently, I wrote a paper which gives some examples of the determination of sodium in various foods. You can download a PDF copy of the paper "Novel method for determination of sodium in foods by thermometric endpoint titrimetry (TET)" by clicking on the link. It was published in the January 2014 edition (Volume 3, Number 1B) of the open-access Journal of Agricultural Chemistry and Environment. If you don't have much time, there's a condensed version as a presentation-style PDF which can be downloaded from here. 

Goodbye to Gove (Part 2)

"Part 1" of my "Goodbye to Gove" dealt with one of the more significant technical challenges we faced in the laboratory during the early years of the Gove alumina refinery, which Rio Tinto Alcan is now in the process of closing down. This second part deals with the most critical challenge to the still young refinery, in which the lab. played an important part.

I've mentioned the word "fun" in Part One of these reminiscences of my technical life at Gove. Fortunately, there was more fun to come after we got the Bayer liquor analysis problem sorted out, which fortuitously put us in good shape for the next challenge. A few years after start-up, we were put in the position of changing the type of alumina that the company produced. If we didn't change the alumina product, the Gove refinery would go out of business.

A short explanation. Aluminium metal is smelted from alumina, Al2O3, That alumina is produced by decomposing aluminium hydroxide, Al(OH)3 at high temperatures.

In the illustration above, the red stuff is the bauxite, from which the aluminium hydroxide is refined (the white stuff). The white stuff is smelted to produce aluminium metal.

To produce aluminium, the alumina is put into a large carbon-lined electrolysis cell (a "pot"). The alumina is dissolved in molten cryolite, Na3AlF6, and lots of electricity is used to reduce the alumina to aluminium metal. You can read a description of the process here. The type of alumina the Gove refinery was designed to make was called "floury" alumina, which was a good descriptor. If you pinched a bit of this alumina between your fingers, it made little peaks, just like finely milled baking flour. It comprised mainly alpha-alumina (corundum), and was made by calcining Al(OH)3 along with a trace of AlF3 as a catalyst at very high temperatures, about 1200 deg. C.

There were process advantages in making floury alumina. Plants making floury alumina could be highly productive, making a lot of alumina per cubic metre of the recirculating aluminate liquor in the plant. There were manufacturing advantages to the smelters as well. However, there was one overwhelming disadvantage - these smelters were highly polluting. When the carbon anodes in the smelting pots burnt, the off-gases which also contained fluoride-containing gases and particulates polluted the surrounding countryside. Many of the smelters would scrub these off-gases with water, but they weren't very efficient. The solution was to employ a property of alumina to contain the fluoride in the smelting pots, and not release it into the environment.

If you don't calcine the alumina all the way through to corundum, you have a product which possesses a high adsorption affinity for all sorts of gases and gas-entrained fine particulates. The smelter design could be changed first to put lids on the pots, and then to lead the off-gases over the incoming alumina feed to the pots. Thus the potentially polluting fluoride could be recycled back to the pots, instead of escaping into the atmosphere. Modern aluminium smelters are highly efficient and essentially non-polluting. Trouble was, we weren't making the right kind of alumina. It wasn't just a case of calcining our product less, we would also have to make the particles coarse and able to withstand the rigours of the new dry gas scrubbing process. 

The scanning electron micrographs at left illustrate a coarse particle of agglomerated aluminium hydroxide, and below it, a particle of the coarse "sandy" alumina which is produced by calcining the aluminium hydroxide.
We didn't know how to make this product. Our parent company Alusuisse approached companies who did know how, but they held the technology very tightly. The technology could be purchased at a crippling price, but it would also result in a considerable reduction in the production capacity. The company faced a stark choice: either pay the exorbitant asking price and suffer a loss of production as well, or be eventually obliged to close down due to market pressure. Alusuisse did neither, thanks to their brilliant chemist and engineer, Dr Otto Tschamper. Dr Tschamper invented a process which held the promise of maintaining plant productivity while manufacturing a grade suitable for use in modern smelters. It was a massive improvement over the technology being used by our competitors. Dr Tschamper told me later that when he first announced the new technology at a technical meeting in the USA, he was laughed at. It's nice when you eventually get the last laugh, isn't it?

The technology had been successfully trialled in Europe, now the confirmatory work had to be done at Gove. Fortunately, our lab. was up to the challenge. Although Alusuisse wasn't originally keen on the idea, we had built up some considerable expertise in modelling plant processes at the lab. scale in order to service the demands of our process engineering colleagues of the technical department. We also had the new thermometric titration liquor analysis, which played a critical role in accurately measuring the mass balances required in evaluating the new process.

I was also fortunate to have a staff of excellent graduate chemists, among them Hans-Peter Breu, who would take a leading role in solving the many problems involved in adapting the new process to the Gove plant through clever experimental design and execution. Cut off from the mainstream of the then highly secretive world of alumina R&D, we had to teach ourselves. Firstly, we had to learn how to make coarse, strong gibbsite particles, then we had to learn how to do this in Gove plant aluminate liquor which was heavily contaminated with organic carbon compounds whose source was the Gove bauxite itself. The process which had worked in Europe didn't work with the organic-laden Gove liquor. It was an exciting time as we gradually learned how to make it work in laboratory-scale reactors. We had no access to the American laboratory test technology, so we had to learn everything from scratch. It wasn't just exciting, it was fun. 

I left Gove around the time of the successful pilot plant tests, firstly to work for Dr Tschamper in Zurich, then later to lead a laboratory supporting Alusuisse' alumina operations around the world in their research institute in Neuhausen, Switzerland. Hans-Peter Breu kept on developing his expertise in the highly successful new process, seeing it implemented and adapted in alumina refineries around the world. 

I heard the other day that after the refinery is shut down, the lab. staff will be reduced to just three, as activities at Gove will comprise just the mining and export of bauxite. 

A sensor-ble solution

A confession: I like cool stuff. I like products which solve problems. Being an analytical chemist, I particularly like products which solve problems in analytical chemistry. Not so long ago, I was shown a new development from Metrohm which I regard as just straight out, simply cool. It's an ion selective probe for calcium determinations, which uses replaceable, thick-film technology sensor tips.


 Now, as you will note from previous posts, my niche speciality is thermometric endpoint titrimetry (TET). In comparison with TET, I don't know all that much about measurement with potentiometric sensors outside of pH electrodes, and previous experiences with ISE's haven't been all that positive. However, this new approach by Metrohm seems to be a most pragmatic approach to the problem of limited service lives of polymer membrane ISE probes, and that is, simply replace just the sensing tip rather than the entire probe.

I guess that following through on this pragmatic approach, they've chosen a Ca-selective probe, as this could have considerable market appeal in the titrimetric analysis of water hardness. It will be interesting to see how the market accepts it, and if they follow this with tips which are selective for other ions. 

Goodbye to Gove (Part 1)

Late in 2013, Rio Tinto Alcan announced it would close down it's alumina refinery on the Gove peninsula of Australia's Northern Territory. I felt sad at this decision, although I understand the business decisions behind this. The reason for my sadness (as well as that of my wife) is that the years that we spent at Gove were some of the happiest of our lives.

Some background: alumina is the oxide of aluminium from which aluminium metal is smelted. The alumina is isolated as a pure compound from its chief ore, bauxite. Although alumina can be made from other aluminium sources such as clay, extraction from bauxite offers the easiest and most economical route. Bauxite can be thought of as what's left from a rock which contains aluminium after it has been subject to weathering over very long geological time periods under certain conditions of rainfall and temperature. The most economical bauxites to process tend to be found in tropical regions. Bauxites which contain the highest proportions of gibbsite, gamma-Al(OH)3 are the most highly prized, because they require less energy to process. The Gove peninsula is located only 11 degrees south of the equator, and the bauxite there has a high proportion of gibbsite.

Here's where Gove is located, relative to the rest of Australia:


It's a remote place. The original majority owner and technical manager of the mine and refinery Swiss Aluminium Ltd (or Alusuisse) made a documentary for their shareholders entitled "Keine Strasse Fuehrt Nach Gove" or "No Roads Lead to Gove", which was the truth. Everything that came into Gove came by sea via coastal freighter or barge or by air. The 4WD track out to Katherine was used by adventurous spirits travelling in convoy during the "dry" season (June to September).

For nearly six years, we called this place home, and we came to love it. My wife recalls that feeling of coming home as our plane bringing us back from leave flew over the bauxite mine, a hematite-red gash in the tropical woodlands.



As an amateur photographer, I loved the intensity of colour that the "wet" (monsoon) season brought, and I recall waiting for the bus to work in the mornings, gazing eastwards over the Arafura sea as the sun rose as a glowing orange ball, tingeing the gathering clouds which would later dump their cargo of rain in near-solid masses of water.

For me, there was fun to be had on two levels in Gove. There was the social aspect, where lots of mainly young people with young families came together. There were barbecues, dinner parties, and a lot of sport. In those early days at Gove, we made our own fun.

The second type of fun for me were the technical challenges. Although by profession I am a chemist, for the duration of the start-up of the plant I worked as a process engineer, responsible for starting up one of the unit processes of the plant. After a couple of years, I was asked to take over management of the process control laboratory. 

So, how can you have fun in a place like this?

The first real challenge had to do with analytical chemistry, more specifically the analysis of the process liquor circulating in the plant. Let me explain the significance. The process used in alumina refineries around the world is called the Bayer Process, name after the Austrian chemist Karl Josef Bayer, who invented the alkaline route to the production of alumina in 1888. It's really a very simple process in principle. Bauxite is an ore containing mainly aluminium hydroxide and oxiyhydroxides, iron and titanium oxides, and silica in the form of kaolinite and quartz (fellow ex- and present alumina workers, please forgive this and following over-simplifications). The alumina values are separated from the other minerals by dissolving them with caustic alkali to form a supersaturated aluminate solution. After separation from the "red mud" gangue, the clear supersaturated aluminate solution is cooled and seeded with Al(OH)3. This causes some of the aluminate content of the liquor to decompose to Al(OH)3, which is then filtered, washed, and calcined at high temperature to alumina, Al2O3. The aluminate-depleted liquor is then recycled to dissolve more aluminium values from incoming bauxite. I'll talk about this in more detail in a later post. Essentially, the Bayer Process can be described in the reversible reaction:

Al(OH)3 + OH(-) <> Al(OH)4(-)

Our problem was in the manual, indicator-based titration method gifted us by the technology provider of the plant. Every operator-analyst saw the endpoint differently, and to add to the misery, the reaction behind the titration wasn't stoichiometric. The net effect that the production department didn't trust the results the lab. was issuing, and wouldn't run the risk of driving the process to the point where it was most efficient and where the profits are made.

A predecessor of mine had purchased, but never put the effort into implementing an early type of thermometric titrator. I saw it as our last best hope of solving the problem. Given that all my lab. supervisors were flat out with their daily tasks, it fell to me to do the development work necessary. Being a stubborn fellow, I kept at it until I felt I had a viable method. Then came the really difficult bit. We had to prove that it would actually control the process. We did lab. experiments on mass balances, and then tracked the process in parallel with the existing liquor analysis procedure. We proved we could predict the bauxite charge to within 1 tonne in 150, while the existing procedure couldn't close mass balances, and couldn't predict anything worthwhile. Still, we had to overcome opposition and even some hostility from the production and process engineers. I was later reminded of something the great Italian management advisor Niccolo Machiavelli wrote in his work "The Prince": "It should be borne in mind that there is nothing more difficult to handle, more doubtful of success and more dangerous to carry out than initiating changes (in a state's constitution). The innovator makes enemies of all those who prospered under the old order, and only lukewarm support is forthcoming from those who would prosper under the new". Substitute "analytical method" for "state's constitution" and you get my drift.

We persevered, and unwittingly at the time, provided the analytical tool that would permit the successful implementation of a radical change in the process necessitated by the world demand for a change in the type of alumina required by modern smelters. I'll talk about the laboratory's role in this new process in a later blog. 

There are a couple of footnotes. Firstly, I was told some years later that the change in the analysis procedure had been responsible for the production of an extra 50,000 tonnes of alumina per annum with no additional process costs. At a then price per tonne of approximately US$ 200, I'll let you do the math on the positive benefit to the bottom line of the company. Secondly, this positive experience with thermometric titrimetry led me years later to co-develop a modern, computer-driven automated thermometric titration system, whose enabling technology is now incorporated in the Metrohm 859 Titrotherm.

Where have all the chemists gone?

A long while ago, the folk singer Pete Seeger wrote a song "Where have all the flowers gone?" It was a favourite of the pretty, soulful girls with ironed-straight long hair who sang in the coffee houses of my youth.  In my work with industry over the past years, I could almost sing to the same tune "where have all the chemists gone?". Where indeed, for they seem to be few and far between in many quality control laboratories these days.

For those of us at the pointy end of customer contact in the analytical instrumentation game, it's becoming increasingly difficult to find people who have the technical knowledge to understand and successfully operate relatively simple instruments. I have personal experience of a large food company with a factory in my home city where there is no analytical chemist on the staff. I was involved in the installation of a titration system and training when it was sold two years ago. Our point of contact is the "technician" who is supposed to provide in-house support to the factory workers who do the actual analyses. The "technician" is actually a terribly nice bloke, but with absolutely no background in chemistry whatsoever. Over the past two years, he has been in frequent contact with the sales staff, expecting them to sort out simple problems which are principally of his own making. In another case, I did the installation of another system in a chemical packaging company where there are no chemists on the staff. They thought that it was perfectly reasonable to expect that included in the purchasing price was an ongoing commitment to sort out their problems as they occur. I stress that overwhelmingly, these problems stem not from equipment or component failure, but purely from a lack of understanding as to what they are doing. I feel a suitable analogy would be walking into a car dealership and expecting the salesperson to teach you how to drive as part of the purchase price of the car. A colleague recounted a similar experience of his, where the previous job of the laboratory supervisor of a factory belonging to his customer (a large chemical concern) was  as a pastry cook. His unqualified laboratory staff have reportedly appallingly bad analytical habits, and resolutely refused to listen to any advice as to how do things properly. It is a fact that unqualified persons can be trained to push the buttons on modern automated analytical instrumentation, but there has to be someone somewhere in the company with the requisite qualifications, experience and knowledge to fix the problems when and if they occur.

Is it reasonable to expect that companies outsource their technical expertise to instrument companies who may have little knowledge of the processes or products? There was a time when development chemists were common in analytical laboratories. There was a realization that improvements in analytical methods lead to better process control, better raw material utilization, and less wastage, all activities which drive profits to the bottom line of a company. So what has happened to bring us to this point? Your comments, please.

Here I am again....

It has been a long while between posts. More than six years, actually. I started this blog with the intention of promoting the little-known technique of thermometric titrimetry. However, instead of just talking about it, I have been involved in getting it installed in process and quality control labs around the world. After my company sold our technology to Metrohm AG, I have been supporting their marketing and sales efforts to make it a part of that company's palette of titration techniques. It's been a struggle, but I think that Metrohm is eventually getting there. In itself, that's quite an achievement. A number of companies have tried, but until now, none have succeeded in making the technique a commercial reality. 

Along the way, I've developed a range of applications for thermometric titrimetry across many industries, and even some which are novel to the industry. I've written nearly 130 application notes and countless customer reports; as well as replying to countless emails from customers, applications chemists and salespeople. I've installed instruments and trained customers and Metrohm applications and sales staff all around the world. Sometimes it's been frustrating, and often there's been a lot of hard work, but when a method comes together and you've solved a customer's problem, there's a lot of satisfaction. In most cases, it's also been fun.

Now it's time to kick back a little, and take it a little easier. I'm still working on new applications, but at the moment confining myself to helping local colleagues. I've also got a little time to think about other things, and perhaps post some of these ramblings here. Let's see what develops.