Nanoparticles and In-Situ Energy

advertisement
Alberta Ingenuity & CMASTE
“Nano”; A New Addition to Industry
Now sometimes it is great to be big but with the advancements in technology and industry small
is the desired attribute. There are many researchers and facilities at universities that are currently
working towards small devices such as microlasers (ultra-small semiconductor lasers), nanoparticles and
new readout heads known as magnetic multilayers for computer memory storage. Now how small of
devices are scientists working with? Nanoparticles are measured in d.nm which means diameter in
nanometer. The prefix for this measurement is “nano” which means 10-9 or a billionth of a meter.
In the Alberta Oil sands new techniques using nanoparticles are being created for oil recovery. In
the industry there are new methods called in situ which means in place. One of the in situ methods uses
nanoparticles that are deposited into the oil reservoir. The nanoparticles are catalysts that increase a
reaction down in the reservoir to allow the bitumen to be piped out of the reservoir. This is quite a
development as surface mining is where large construction equipment literally digs out the bitumen. But
they can only retrieve 20% of the bitumen. These in situ methods provide less environmental impacts to
the area, better bitumen recovery and are more efficient and economical.
To create these nanoparticles for bitumen recovery two micro-emulsions are combined. A
micro-emulsion is optically isotropic which means it appears to be one solution; a homogeneous
mixture. These are highly sensitive to temperature but they are stable at room temperature. In order to
create a micro-emulsion it requires a non polar, polar solution and surfactant. There are two main types
of micro-emulsions. The first type of oil in water (O/W) where there are tiny little drops of oil
surrounded by surfactant and in water. The second type is water in oil (W/O). In this micro-emulsion
there are tiny droplets of water surrounded by surfactant in oil. The surfactant is very important to allow
the oil and water to mix. One example of a micro-emulsion that has a nanoparticle as a product is found
by the following equation.
Co(CH3COO)2
(aq)
+ 2NaOH (aq)  Co(OH)2
(s)
+ 2NaCH3COO
(aq)
In this example equation above, heptane was the non polar solution, dioctyl sulfosuccinate sodium salt
was the surfactant and the polar portion was a salt solution.
To create the first micro-emulsion a cobalt acetate solution was added to the heptane and
dioctyl sulfosuccinate sodium salt. It is vitally important to ensure that the surfactant has completely
dissolved in the heptane otherwise the micro-emulsion will not occur. The second was a solution of
sodium hydroxide added to heptane and dioctyl sulfosuccinate sodium salt. The creation of
nanoparticles occurred when the sodium hydroxide micro-emulsion and the cobalt acetate solution are
mixed.
Document1
Alberta Ingenuity Centre for In-Situ Energy
1/6
Alberta Ingenuity & CMASTE
Once the two microemulsions are combined a reaction occurs
within the droplets so that Co(OH)2 is a product and which is the desired
nanoparticle. In order to use the particles they need to be very tiny.
Scientists are striving to create the nanoparticles as small as possible so that
there is more surface area for the reaction. To measure the size of the
particles an instrument called Zetasizer Nano Series is used. Zetasizer Nano
Series determines the size by first measuring the Brownian motion of the
particles in a sample using Dynamic Light Scattering (DLS). It then interprets
a size from the Brownian Motion Theory. In any liquid particles that are
Zetasizer Nano Series,
Malvern Instruments Ltd.
suspended in it move around randomly. The Zetasizer system uses the
speed of their movement to determine the size of the particle; small particles move more quickly and
larger particles move less quickly. The Zetasizer takes many pictures of the samples at quick succession
to see how much the particle has moved and then uses the theory to determine the size of the particle.
Zetasizer method for measuring size of a particle (Zetasizer User Manual, Malvern Instruments Ltd.)
Document1
Alberta Ingenuity Centre for In-Situ Energy
2/6
Alberta Ingenuity & CMASTE
To prepare the samples for the machine a small amount of the micro-emulsion is
deposited into a cuvette. The sample size is about 0.75 mL. A lid is put on the cuvette and
placed into the Zetasizer. The machine runs three analyses of each sample and multiple
“pictures” in each analysis. Once all the analyses are complete a computer program
creates a graph of the size of the particles. For this analysis 3 measurements were taken;
cobalt micro-emulsion, sodium hydroxide micro-emulsion and the combined microCuvette filled with emulsion.
sample for testing
in Zetasizer Nano
Series
So through new technology scientists are able to create objects and devices that
are a billionth of a meter in size. These new materials have revolutionized many
industries for more efficient, economical operations and have even made things
possible. Nano sized objects have many industry uses that range from computer storage, medical
interventions and bitumen recovery. It is a direction that the science community is now embracing. A
common saying is that “size does not matter” and it is very true. These tiny objects have allowed never
before practices to emerge and be highly successful.
Graphs of the Size of Particles using the Zetasizer Nano Series:
Document1
Alberta Ingenuity Centre for In-Situ Energy
3/6
Alberta Ingenuity & CMASTE
Document1
Alberta Ingenuity Centre for In-Situ Energy
4/6
Alberta Ingenuity & CMASTE
Student Questions:
1. If a nanoparticle was the size of a grain of rice how large would a school desk be.
2. Explain why are researchers are working towards nanoparticles in the Oil sands in Alberta and
give one example.
3. Below are the reactants for making some nanoparticles.
Co(CH3COO)2 (aq) + 2NaOH (aq) 
Emulsion 1
Emulsion 2
a) Predict the products and the type of reaction that occurred.
b) How does acetate behave in this reaction?
c) How could you verify what state the products would be?
d) What colour, if any, would the final solution appear to be?
4.
a) In your own words describe how to use a Zetasizer Nano Series machine.
b) Give two reasons that the Zetasizer machine runs more than one analysis.
c) In what units are the nanoparticles measured in the Zetasizer.
Document1
Alberta Ingenuity Centre for In-Situ Energy
5/6
Alberta Ingenuity & CMASTE
5. Using the Zetasizer graphs provided above.
a) Write a detailed summary to explain how to read the graphs.
b) Compare and contrast the size of the particles in the cobalt acetate and the sodium
hydroxide solution.
c) Analyze the final micro-emulsion which produced the nanoparticle.
6. Describe one area of your life that you think nanoparticles could be utilized.
Document1
Alberta Ingenuity Centre for In-Situ Energy
6/6
Download