Preliminary Tests of Innovative Eco-Friendly Furfuryl Resins and Foundry Sand Mixtures Based on These Resins
Jadwiga Kamińska 1  
,   Sabina Puzio 1  
,   Michał Angrecki 1  
,   Mateusz Stachowicz 2  
,   Anna Łoś 3  
ŁUKASIEWICZ – Foundry Research Institute, Department of Technology, Zakopianska 73, 30-418 Cracow, Poland
Wrocław University of Technology, Faculty of Mechanical Engineering, Chair of Foundry Engineering, Plastics and Automation, Ignacego Łukasiewicza 5, 50-371 Wrocław, Poland
Grupa Azoty JRCh Sp. z o.o., E. Kwiatkowskiego 8, 33-101 Tarnów, Poland
Jadwiga Kamińska   

ŁUKASIEWICZ – Foundry Research Institute, Department of Technology, Zakopianska 73, 30-418 Cracow, Poland
Data publikacji: 01-10-2019
J. Ecol. Eng. 2019; 20(9):285–292
The foundry industry in Poland and EU member states is growing steadily. Currently, foundries are facing the problem of increasing requirements, which enforce the production of castings characterized by high dimensional accuracy and surface smoothness with parallel elimination of casting defects. Castings are mostly made in moulding sand mixtures, which are also subject to more and more stringent requirements to meet the above-mentioned casting acceptance conditions. Additionally, moulding sands should ensure adequate mould stiffness to avoid the risk of dimensional deformations during pouring of this mould with liquid metal and casting solidification. For these reasons, the production of this type of castings has been dominated by loose self-hardening sands with furfuryl resin, commonly called furan sands. In the group of self-hardening sands with synthetic resins, loose self-hardening sands with furfuryl resin enjoy the greatest popularity. What accounts for this fact is the high level of the reclamability of these sands, the possibility of obtaining castings with high dimensional accuracy, the ability to make intricate moulds and cores, the binding process taking place at ambient temperature, and low content of binder. Unfortunately, this technology also has some disadvantages, which include short lifetime of the sand mixture, harmful gases evolving from the sand, and currently also high cost of the sand mixture. The anticipated tightening of environmental protection regulations in EU countries, including limiting the content of free furfuryl alcohol in resins (<25% by mass) and reducing the emission of furfuryl alcohol, formaldehyde and BTEX compounds at workplaces, necessitated the development of a new generation of furfuryl resins friendly to the environment. The article compares the results of testing the strength properties of foundry moulding sands using two types of resins, i.e. the resin of a new generation synthesized by Grupa Azoty JRCh and a commercial resin used in the foundry industry. Additionally, derivatographic studies of the above mentioned sand mixtures were made, and the loss on ignition and the amount of gases emitted by the sand mixture were determined. Melting was also carried out to study the impact of the resin used on the surface quality of iron castings.