Kokkola University Consortium Chydenius

Karleby, Finland

Kokkola University Consortium Chydenius

Karleby, Finland
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Pohjalainen E.,Aalto University | Rasanen S.,Kokkola University Consortium Chydenius | Jokinen M.,Aalto University | Yliniemi K.,Aalto University | And 7 more authors.
Journal of Power Sources | Year: 2013

Less expensive and greener aqueous electrode preparation processes are essential for the market penetration of lithium ion batteries to mid-scale applications. So far only carboxyl methyl cellulose (CMC) binder has been adopted for industrial use to fabricate carbon electrodes without harmful organic solvents but this process is prone to bacterial growth. In this study a new binder candidate, Acryl S020, is introduced for an aqueous preparation process that has been used for preparing Li4Ti5O 12 electrodes for lithium ion batteries. It is shown that with our water based process electrodes with capacities comparable to those electrodes fabricated with the conventional organic solvent based process with the PVDF binder are obtained. Moreover, our lithium titanate electrodes with the Acryl S020 binder show high capacity retention and they can be operated at sub-zero temperatures. Electrodes were also fabricated with pilot-scale gravure printing and slot-die coating methods and they showed stable cycles lives of 500 cycles. © 2012 Published by Elsevier B.V. All rights reserved.


Hernoux-Villiere A.,Kokkola University Consortium Chydenius | Hernoux-Villiere A.,University of Savoy | Lassi U.,Kokkola University Consortium Chydenius | Lassi U.,University of Oulu | Leveque J.-M.,University of Savoy
Ultrasonics Sonochemistry | Year: 2013

An advanced dual frequency ultrasonic coaxial reactor enabling simultaneously low and high frequencies irradiating in the same direction was developed to focus both mechanical and chemical effects on a concentrated area. The prototype was straightforward employed for the conversion of a starch-based industrial waste into sugars. © 2013 Elsevier B.V. All rights reserved.


Hernoux A.,University of Savoy | Hernoux A.,Kokkola University Consortium Chydenius | Leveque J.-M.,University of Savoy | Lassi U.,Kokkola University Consortium Chydenius | And 3 more authors.
Carbohydrate Polymers | Year: 2013

In this exploratory work, the comparison of the utilisation of different non-conventional technologies (ultrasound and microwave irradiations) for the depolymerisation of a complex industrial starch-based waste into reducing sugars was investigated. Reducing sugars could then be converted into higher value-added compounds such as higher alcohols. The experiments were performed on three different starting materials named as 'Potato flour', 'Wet potato sludge' and 'Dry potato sludge'. The conversion of 'Potato flour' into reducing sugars reached in acidic conditions 61% within an hour under microwave irradiation, 70% and 84% within 120 min under low and high frequency ultrasonic irradiation, respectively. © 2012 Elsevier Ltd.


Hernoux-Villiere A.,Kokkola University Consortium Chydenius | Hernoux-Villiere A.,University of Savoy | Leveque J.-M.,University of Savoy | Karkkainen J.,University of Oulu | And 4 more authors.
Catalysis Today | Year: 2014

Development of a simple route for the catalytic conversion of starch-based industrial waste (potato peels) and potato starch into reducing sugars was investigated in two ionic liquids for comparison - 1-allyl-3-methylimidazolium chloride [AMIM]Cl and 1-(4-sulfobutyl)-3-methylimidazolium chloride [SBMIM]Cl. Over a two hour period, a 20 wt% solution containing up to 43% and 98% of reducing sugars at low temperature in aqueous [SBMIM]Cl was achieved for the starch-based waste and the potato starch, respectively. In addition, the use of microwave and low frequency ultrasound to perform the depolymerisation of the raw starch-based material was explored and compared with conventional heating processes. © 2013 Elsevier B.V.


Kilpimaa S.,University of Oulu | Kuokkanen T.,University of Oulu | Lassi U.,University of Oulu | Lassi U.,Kokkola University Consortium Chydenius
BioResources | Year: 2013

The aim of this research was to study the physical and chemical properties of fly ashes from combustion process and carbon residue from gasification process whilst comparing the results between these two types of solid residues, as well as against literature values. Ashes from the combustion process and carbon residue from gasification process are formed in different conditions, and it can be assumed that they will be best suited to contrasting utilization applications. The most notable differences between these types of solid residues were that the carbon content and loss-on-ignition value was higher for gasification carbon residue, and the liming capacity was higher for combustion ashes. The calculated liming capacity for combustion ashes and the fact that these ashes were strongly alkaline, together with high nutrient concentrations, indicate that combustion ashes can provide a liming effect. As a result, these ashes could potentially be utilized as a soil conditioning agent to substitute for commercial lime. The carbon content in gasification carbon residue was high which indicates, together with high porosity, that carbon residue would be an ideal sorbent and it could also be used as a fuel.


Kilpimaa S.,University of Oulu | Runtti H.,University of Oulu | Kangas T.,University of Oulu | Lassi U.,University of Oulu | And 2 more authors.
Chemical Engineering Research and Design | Year: 2014

Carbon residue is a by-product from the biomass gasification process in which heat and power are generated. In this study, carbon residue was chemically activated and the effect of this activation process on the adsorption properties was investigated. A chemically activated carbon residue was used as an adsorbent for the removal of phosphate and nitrate in an aqueous solution. The general idea is that the carbon residue could first be used as a low cost adsorbent for phosphate and nitrate ions removal, e.g. from wastewaters, and after that it could be used as a nitrogen and phosphorus rich forest fertiliser.Based on the results, the most effective pH value for phosphate removal was 6, 4 and 6 for activated carbon residue, carbon residue and activated carbon respectively. Optimum pH value for nitrate removal was 6 for activated carbon residue and carbon residue, and 4 for activated carbon. The optimum concentrations for the initial phosphate solutions for activated carbon residue, carbon residue and activated carbon were 25, 50 and 25mgL-1 respectively. For nitrate, the optimal concentration was 25mgL-1 for all adsorbents. Phosphate and nitrate adsorption kinetics were well fitted by the pseudo-second-order kinetic model for all studied adsorbents. Phosphate and nitrate adsorption onto activated carbon residue obey well Langmuir adsorption isotherm. © 2014 The Institution of Chemical Engineers.


Romar H.,Kokkola University Consortium Chydenius | Tynjala P.,Kokkola University Consortium Chydenius | Tynjala P.,University of Oulu | Lassi U.,Kokkola University Consortium Chydenius | Lassi U.,University of Oulu
BioResources | Year: 2013

The existence of tar compounds in producer gas is one of the major problems found in biomass gasification; these compounds need to be removed before the producer gas can be used. In order to predict the need for producer gas cleaning for catalytic conversion into traffic fuels and chemicals, the gas has to be accurately characterised and defined. In this study, tar compounds from producer gas of two small-scale downdraft gasifiers were collected, identified, and quantified. Based on the results, there were several tar compounds present in the gas flow. Toluene and naphthalene were the most abundant compounds, totalling more than 70% of the total volume of tars while tar concentration levels were in the range of 200 to 400 mg/Nm3. These concentrations were found to be consistent with values presented for similar-type gasifiers using wood chips.


Tolonen E.-T.,University of Oulu | Sarpola A.,Oulu Water Alliance Ltd. | Hu T.,University of Oulu | Ramo J.,University of Oulu | And 2 more authors.
Chemosphere | Year: 2014

The aim of this research was to investigate whether by-products from quicklime manufacturing could be used instead of commercial quicklime (CaO) or hydrated lime (Ca(OH)2), which are traditionally used as neutralization chemicals in acid mine drainage treatment. Four by-products were studied and the results were compared with quicklime and hydrated lime. The studied by-products were partly burnt lime stored outdoors, partly burnt lime stored in a silo, kiln dust and a mixture of partly burnt lime stored outdoors and dolomite. Present application options for these by-products are limited and they are largely considered waste. Chemical precipitation experiments were performed with the jar test. All the studied by-products removed over 99% of Al, As, Cd, Co, Cu, Fe, Mn, Ni, Zn and approximately 60% of sulphate from acid mine drainage. However, the neutralization capacity of the by-products and thus the amount of by-product needed as well as the amount of sludge produced varied. The results indicated that two out of the four studied by-products could be used as an alternative to quicklime or hydrated lime for acid mine drainage treatment. © 2014 Elsevier Ltd.


Kilpimaa S.,University of Oulu | Runtti H.,University of Oulu | Kangas T.,University of Oulu | Lassi U.,University of Oulu | And 2 more authors.
Journal of Industrial and Engineering Chemistry | Year: 2015

Carbon residue obtained as a by-product from wood gasification process was employed as a precursor for preparing adsorbent by physical activation. Adsorbent with BET surface area 590m2g-1 and pore volume of 0.335cm3g-1 was prepared and used as an adsorbent for phosphate and nitrate removal. The optimal pH and initial concentrations for phosphate and nitrate removal were determined. The kinetics showed that the adsorption data followed pseudo-second-order kinetics. The isotherm analysis indicated that the adsorption data can be represented by the Langmuir model. Results showed that activated carbon residue is suitable adsorbent for phosphate removal. © 2014 The Korean Society of Industrial and Engineering Chemistry.


News Article | March 7, 2016
Site: www.materialstoday.com

The high energy density of lithium-ion (Li-ion) batteries make them a popular energy storage technology, especially in mobile applications such as personal electronics and electric cars. However, the materials currently used in Li-ion batteries are expensive, while many of them, like lithium cobalt oxide, are also difficult to handle and dispose of. What is more, batteries using these materials have relatively short lifetimes. These shortcomings have led scientists to develop novel materials for next generation Li-ion batteries: two promising electrode materials are lithium titanate and lithium iron phosphate. The materials are readily available, safe to use, and easy to dispose of or recycle. Most importantly, batteries manufactured using these materials have significantly longer cycle and calendar lifetimes compared to current battery technologies. However, these new materials are currently hampered by their low electrical conductivity. Scientists at the University of Eastern Finland (UEF) in Kuopio have now come up with a potential solution to this low conductivity problem, which is reported in a paper in the Journal of Alloys and Compounds. "The electric conductivity problem can be solved by producing nanosized, high surface area crystalline materials, or by modifying the material composition with highly conductive dopants, " explains Tommi Karhunen, a researcher in the UEF Fine Particle and Aerosol Technology Laboratory. "We have succeeded in doing both for lithium titanate in a simple, one-step gas phase process developed here at the UEF Fine Particle and Aerosol Technology Laboratory." "The electrochemical performance of Li-ion batteries made out of the above mentioned material is very promising," says Jorma Jokiniemi, director of the UEF Fine Particle and Aerosol Technology Laboratory. "The electrochemical properties were studied in collaboration with Professor Ulla Lassi's group from Kokkola University Consortium Chydenius. The most important applications lie in batteries featuring, for example, fast charging required for electric buses, or high power needed for hybrid and electric vehicles." This story is adapted from material from the University of Eastern Finland, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier. Link to original source.

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