From forest industry waste streams to new urethanes and polyurethanes: value from Lignin degradation

Researcher: Veronika Badazhkova,  Doctoral Student, Åbo Akademi University

Supervisors: Professor Reko Leino (Principal investigator), Dr. Risto Savela and 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, due to their highly versatile properties, are 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 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, thus allowing the minimization of chemical waste formed in process. The objective of this project is to discover suitable methodologies for the utilization of waste streams from Finnish forest industry to facilitate the 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)

 

Description of the project: Scandium provides technological advantages, particularly in solid oxide fuel cells and aluminum alloys, in respect of transportation applications due to its capacity to increase strength and weldability. The focus of this project is to develop a material and cost-efficient process to extract scandium from the 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 scandium production is currently only 15 t/a. Given the limited volume of the current global scandium production, the Kiviniemi deposit provides a potential new source for the expectedly increasing demand of this unique rare earth metal, classified as a critical raw material for the 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 project includes high-temperature upgrading of the concentrate to produce Sc-containing amorphous phase along with crude iron. The 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 relevant journals. This project promotes the beneficiation of the 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.

 

Comparing the impact of continuous cover forest management and rotations forest management on long-term soil carbon storage

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

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

 

Description of the project: The project promotes the sustainable use of forest soils. Forest soil is a very important natural resource that holds many functions. It provides a 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 extent,  as organic matter in the soil. Soil organic matter greatly affects the productivity of the soil and thereby 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 higher long-term soil carbon storage.

 

 

 

Detailed solution chemistry of flotation circuits in Nordic conditions

Researcher: David Sibarani (M.Sc.), Doctoral student, Aalto University

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

 

Description of the project: 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 a 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 L. x P. tremuloides Michx.) is one of the fastest growing tree species in Finland. The high yield capacity and chemical properties of aspen indicate its promising potential for biochemicals and green energy.

Aims of the project

We study the chemical properties of hybrid aspen clones for production of added-value chemicals. We concentrate on aspen bark as an 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 the sustainable use of Finnish natural resources

To remain competitive in future bio-economy, the Finnish forest sector must constantly come up with novel products. Hybrid aspen has potential to become a 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 the comprehensive utilization of aspen biomass. Aspen bark may provide an alternative source for fossil-based chemicals.

Expected results and deliverables

The project provides forest industries and future bio-refineries with a knowledge base on hybrid aspen biomass, especially the under-utilized bark, and its potential for added-value applications or template chemicals including:

1) catalytic conversion of wood-derived substances into valuable bulk chemicals

2) application of suberin acids in coatings

3) use of acidic distillates for plant protection.

 

 

New methods for Pure Rare Earths / PuREE

Researcher: M.Sc. Santeri Kurkinen,  Department of Separation Science, LUT University

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

 

Description of the project: Rare earth elements (REEs) 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. REEs are not particularly rare in Earth’s crust, but they are difficult to extract and purify cost-effectively.

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

REEs can be leached from PG with, e.g., sulfuric 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, thus increasing the leaching yield.

The PuREE project aims at further developing the “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.

The 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