From Forest Industry Waste Streams to New Urethanes and Polyurethanes: Value from Lignin Degradation

Researcher: Veronika Badazhkova (Doctoral student)

Supervisory team: Professor Reko Leino (Principal investigator), Dr. Risto Savela, Dr. Patrik Eklund

Site of Research: Johan Gadolin Process Chemistry Centre, Laboratory of Molecular Science and Technology, Åbo Akademi University

Description of the project: Polyurethanes belong to the most important polymeric materials and are, due to their highly versatile properties, used in several different applications, including tubings, footwear, industrial machinery, coatings and paints, elastic fibers, rigid insulations, soft flexible foams and medical devices. Traditionally, polyurethanes are produced from isocyanate monomers, which are often are highly toxic and moisture sensitive. Alternatively, properly sized cyclic carbamates could be polymerized by cationic ring opening polymerization. A possible biomass based feedstock for polyurethanes could be lignin. It is one of the most abundant organic polymers available on earth, constituting ~30% of non-fossil based carbon and approximately 20-35% of dry mass of wood. Comprised of aromatic monomers, lignin can be considered as one of the most abundant natural resources for future aromatic platform chemicals. Suitable cyclic carbamates could be prepared catalytically from lignin by alcohol amination reaction followed by carbon dioxide fixation allowing the minimization of chemical waste formed in process. The objective of this project is to discover suitable methodologies for utilization of waste streams from Finnish forest industry for production of biomass based polyurethanes.

 

Development and modification of Scandium production process

Researcher: M.Sc. Rita Kallio

Supervisors: Professors Timo Fabritius (metallurgy), Saija Luukkanen (mineral processing) and Ulla Lassi (hydrometallurgy)

Scandium provides technological advantages particularly in solid oxide fuels cells and aluminum alloys in respect of transportation applications due to its capacity to increase strength and weld-ability. The focus of this project is to develop a material and a cost-efficient process to extract scandium from recently discovered Kiviniemi mafic intrusion, which is a primary scandium occurrence with estimated 13.4 Mt @ 163 ppm Sc. Based on the geochemical characteristics of scandium, its enrichment to ore grades by geological processes is scarce. Consequently, the estimated global Sc production is currently only 15 t/a. With such a limited current global scandium production, the Kiviniemi deposit provides a potential new source for expectedly increasing demand of this unique rare earth metal, classified as critical raw material for European Union. There are no other Kiviniemi-type scandium deposits known in Europe. In the Kiviniemi deposit, scandium occurs in pyroxene and amphibole, which respond well to magnetic preconcentration (Figure 1). In addition to the conventional preconcentration methods, the proposed processing scheme investigated in this research includes high-temperature upgrading of the concentrate to produce Sc-containing amorphous phase along with crude iron. Sc-containing amorphous phase is further treated with hydrometallurgical processes to produce the desired Sc2O3-product. The purpose of this research is to investigate the main features and boundary conditions related to each proposed step, the results of which will be published in appropriate journals. This project promotes the beneficiation of Kiviniemi scandium deposit through interdisciplinary research, extending from mineral processing to the pyrometallurgical treatment and hydrometallurgical aspects of scandium extraction.

Figure 1. Stereomicroscope images of dry magnetic separated fractions from the Kiviniemi sample. The dark particles (black and green) represent scandium-containing pyroxene and amphibole, together with ilmenite, iron oxides and sulphides. The red grains are garnet (almandine) and the colourless or slightly yellow/orange grains are mainly plagioclase and potassium feldspar. A-D): 250-500 µm size fraction separated with A) hand magnet, B) Frantz 0.4 A, C) Frantz 0.8 A and D) Nmags; E-H): 125-250 µm size fraction; I-L): 63-125 µm size fraction; and M-P): 32-63 µm size fraction, separated in respective order.

 

Boosting the Use of Fast-Growing Aspen: Green Source of High-Added Value Chemicals and Energy (BoostA)

Researcher: Eva-Maria Roth, Doctoral Student at the University of Helsinki

Supervisors: Kristiina Karhu, University of Helsinki, Assistant Professor at the Department of Forest Sciences
Eeva-Stiina Tuittila, University of eastern Finland, Faculty of Science and Forestry, School of Forest Sciences
Heljä-Sisko Helmisaari, University of Helsinki, Professor at the Department of Forest Sciences

 

Description of the project:  Comparing the impact of continuous cover forest management and rotation forest management on long-term soil carbon storage.

The project promotes the sustainable use of forest soils. Forest soil is a very important natural resource that holds many important functions. It provides habitat for soil biota, enables tree growth and stores carbon. The ability of forests to fix and store atmospheric carbon, has brought them into focus as a means to mitigate climate change. The carbon is stored in biomass and to a greater extend as organic matter in the soil. Soil organic matter greatly affects the productivity of the soil and thus tree growth.

Continuous cover forestry is a management system that was discouraged in Finland until 2014. In contrast to the more common rotation forest management, harvesting in continuous cover forestry does not involve clear-cuts. A continuous forest cover remains permanently. Forests managed with continuous cover forestry were found to have a higher ecological resilience, enabling them to adapt to climate change and react to threats such as bark beetle calamities or storms. My dissertation aims to compare the effects of continuous cover forestry and rotation forest management on long-term soil carbon storage and on the main drivers in the stabilization of soil carbon. I am conducting field studies on experimental plots in central Finland. Because of the reduced soil disturbance during harvests, continuous cover forestry prevents losses of carbon from the soil, which could result in a higher long-term soil carbon storage.

 

 

 

Detailed solution chemistry of flotation circuits in Nordic conditions

Researcher: David Sibarani (M.Sc.), Doctoral candidate.
Aalto University, School of Chemical Engineering, Department of Chemical and Metallurgical Engineering.

Supervisor: Daniel Lindberg (D.Sc.), Associate professor, Principal Investigator and supervisor.
Aalto University, School of Chemical Engineering, Department of Chemical and Metallurgical Engineering.

 

The goal of this project is to study the aqueous chemistry in mineral processing of sulfidic ores, where the water circulation of the flotation circuits are closed, and the same water circulates between the mineral processing plant and the tailing pond. Closed water cycles will change the composition of the water used in the mineral processing, which will be problematic e.g. in flotation processes. The properties of the aqueous phase in the flotation processes has not been studied in detail to any large extent due to lack of proper tools for these studies. In the present project, the goal is to systematically and critically develop thermodynamic databases for aqueous solutions, with the following areas of application:

  • The detailed solution chemistry of the aqueous phase in mineral processing of sulfidic ores, with focus on Nordic conditions.
  • The detailed solution chemistry of acidic leachate waters from mines, as well as the recovery of metals from these solutions.

The project will promote the Finnish mining and metallurgical industry, as well as the development of circular economy through

  • increased utilization and recycling of the process water from flotation processes
  • more efficient utilization of mineral resources
  • Increased metal recovery from depleted mines and waste heaps

The expected outcome is a doctoral thesis, including several scientific papers, as well as a detailed thermodynamic database that can be utilized by the Finnish industry to further optimize metals recovery from complicated processes and streams.

 

Boosting the use of fast-growing Aspen: green source of high-added value chemicals and energy (BoostA)

Researcher: Pasi Korkalo, Research Scientist. M.Sc. (Chemistry), Natural Resources Institute Finland

Supervisor: Tuula Jyske, Senior Scientist, D.Sc., docent (Agr & For), Natural Resources Institute Finland

Researcher Pasi Korkalo

 

Background of the project

Novel bioeconomy approaches call for more and faster production of lignocellulosic biomass and its better-tailored holistic use for higher added-value. Hybrid aspen (Populus tremula x tremuloides Michx.) is one of the fastest growing tree species in Finland. High-yield capacity and chemical properties of aspen indicate its promising potential for biochemicals and green energy.

Aims of the project

We study chemical properties of hybrid aspen clones for production of added-value chemicals. We concentrate on aspen bark as under-utilized raw material. By using extraction and thermochemical distillation, chemical substances are separated for case-studies (Figure).

Figure: Comprehensive utilization of hybrid aspen wood and bark.

How the project will promote sustainable use of Finnish natural resources

To remain competitive in future bioeconomy, the Finnish forest sector must come up constantly with novel products. Hybrid aspen has potential to become more important raw material in Finland, especially as the climate change forces a broadening of the selection of commercially utilized tree species. Our project promotes comprehensive utilization of aspen biomass. Aspen bark may provide an alternative source for fossil-based chemicals.

Expected results and deliverables

Project provides forest industries and future biorefineries a knowledgebase on hybrid aspen biomass, especially under-utilized bark, and its potential for added-value applications / template chemicals:

1) catalytic conversion of wood-derived substances into valuable bulk chemicals
2) application of suberin acids in coatings
3) and use of acidic distillates for plant protection

 

 

New methods for Pure Rare Earths / PuREE

Researcher: MSc. Santeri Kurkinen, LUT University, Department of Separation Science, Yliopistonkatu 34, 53850 Lappeenranta

Supervisors:  Prof. Tuomo Sainio, Dr. Sami Virolainen, both from LUT University

 

Rare earth elements (REE) are a set of 17 elements with extraordinary properties. Their numerous applications include electronics, LEDs, high strength magnets, automotive catalytic converters, and high temperature superconductors. REE are not particularly rare in Earth’s crust, but they are difficult to extract and purify cost-effectively.

Besides ores, REE are found in by-products of minerals processing. Phosphogypsum waste (PG), which is formed in phosphate fertilizer production, may contain 0.2 wt-% of REE. PG is available in huge quantities. In Finland alone, more than 1.5 million tons of PG is produced and piled annually.

REE can be leached from PG with, e.g., sulphuric acid. Interestingly, leaching can be done under very mild conditions if functionalized polymeric particles, called ion exchange resins, are added to the leaching reactor. The polymer particles quickly bind the liberated REE ions from the solution, increasing leaching yield.

PuREE project aims at further developing such a “resin-in-leach” process. Significant improvements in leaching efficiency and selectivity are achieved by optimizing the chemistry of the functionalized polymer. Once the REEs are bound to the polymer, they must be recovered to reuse the polymer. The sustainability of this step is improved by using biodegradable chemicals for REE recovery. Further purification of the REEs is done in a separation column using another type of polymeric separation material.

PuREE project produces new data and process options for sustainable production of REEs from a secondary source in Finland.

 

Dr. Virolainen and M.Sc. Kurkinen being busy in recovering of REES from phosphogypsum