Get to know us: Postdoctoral Researcher Sipi Seisko

Why did you choose the academic work field?

Me getting into the academic work field happened by accident. I was not planning on it. I can still remember that during my master’s thesis I told everyone that I was never going to continue to doctoral studies. Mari Lundström, who was my foreman (and still is) tried to convince me to continue with my studies. And when I gave it more thought, it became clear to me that I still wanted to know more. When I got my master’s degree, I thought to myself, that I had a basic understanding of everything, but I wanted to really focus on just one subject. So, I decided to continue as a doctoral student and now I work as a postdoctoral researcher in the research group of Hydrometallurgy and Corrosion.

What does your typical workday look like?

It is hard to say as a researcher does not clock in and out, finishing everything in eight hours and the next day doing the second step in some process sheet. It is more of working on different parts of the research, be it designing or conducting experiments, analyzing data, writing an article, with each part possibly taking months. But usually the day starts by having a cup of coffee, checking my email and notes, which I have left for myself to remind what has been accomplished and what should be done next. It is important so that I can stay focused, even if the notes just say “Hey Sipi, do this and check this.” It can be dangerous to get sucked into reading about something interesting, and in the end of the day realizing it was not relevant for my research in the big picture.

Right now, I´m doing scientific writing which also includes literature review to find references and learning more about the topic. Usually before this I have collected raw data through the experiments. The data must be analyzed, usually with Excel, to be able to make conclusions about the results. Each part teaches me something new which is nice, so to me the work does not feel boring or repetitive. It is kind of like using the same Lego blocks but putting them together differently each day.

What is your research subject?

My research topic is chloride leaching of gold. So, when we are manufacturing gold from the ore that is rich in gold, we must enrich the gold concentration. The ore contains very little gold even though it is considered to be a profitable amount. Leaching is the process of dissolving the target metals from the larger particulates, leaving impurities undissolved. The new concentrate is then processed further down the line. My research focuses on finding the optimal conditions for the chloride leaching by changing the pH, temperature and initial concentrations of chemicals.

In the gold process there are many unit processes that lead to the pure gold product. One of the unit processes is the leaching process. Nowadays the predominant procedure is cyanide leaching.  The procedure targets the dissolved gold ions which are then complexed with a cyanide ion.

Since there have occurred some spills of cyanide in some plants back in the days, many countries are now starting to ban the cyanidation via their legislation. Therefore, there is a need for a replacement method, one that would be more environmentally friendly. Our solution is to use chlorides to complex the dissolved gold ions. In the future, we can hopefully use sea water and get chlorides from the nature. Then we would not have to add any chlorides as chemicals but utilize the nature's own resources.

Why is chloride leaching not the mainstream method?

The problem is that while chloride leaching is possible, it is not as commercially profitable as cyanide leaching. This is because chlorides are very corrosive substances and the usual stainless-steel reactors and piping cannot be used. More expensive titanium apparatus makes the initial cost of the factory much higher. In addition, the method uses large amounts of chlorides and oxidants. There has not been any commercialized process using the chloride leaching so there might be some other factors to consider as well. By finding the optimal conditions for the process, we can save in heating and materials costs.

How international is your work?

All scientific research is international, as we rely on peer-reviewed research from other scientists for reference and to review our findings. In our laboratory, I would say half of our staff are from abroad, so I am always talking in English at work. During my doctoral studies, I got to travel to conferences around the world where I introduced myself to people from other universities and companies. They helped me to hone my presentation and English skills. My favorite trip was Copper 2016 in Kobe, Japan. The people were so nice and going to a Japanese karaoke room with fellow scientists while everything and everyone spoke in Japanese was an experience!

What are the most and least interesting parts of your work?

I think the most interesting part is learning and figuring out some new results. Especially if the results are similar or conflicting with old data. But, new results in general always feel great. However, because this is not a new topic (it has been researched for over 100 years), there is always a bit of a worry that if you find out something totally new. Have you misunderstood something, or have you done an error in your work? But the most satisfying thing is getting to a conclusion by yourself about why something is happening or what correlates with something else.

Then the least interesting part of my work is maybe the mechanical work involved. For example, inserting thousands of rows of data into Excel and doing the calculations. That is the least interesting part. On the other hand, it can lead to the most interesting part if you can figure out something new with your calculations.

What has been the weirdest thing you have done in your research?

One of the prohibiting factors in chloride leaching is that large amounts of chlorides are needed. This could be offset if we could get the chlorides from sea water. However, we do not have access to normal sea water in the Southern Finland. My colleague gave me the idea to contact Sea Life, which works in cooperation with the Linnanmäki amusement park, and got a sea water sample from chubby seahorses’ pool. The intendent of Sea Life was so nice! This kind of outside the box thinking is very important in research work. While the sample is not that scientific – the ­­­­­­­­­­­­seahorses’ pool water is not easily reproducible around the world – but will work fine for a case study to test our hypothesis.

This interview is conducted by Aleksanteri Kupi and Mikaela Kumlin who have been working during the summer at the School of Chemical Engineering.