Carbon Dioxide Soluble Binders for Environmentally Benign Metal Forming OperationsEPA Grant Number: R831504
Title: Carbon Dioxide Soluble Binders for Environmentally Benign Metal Forming Operations
Investigators: Manke, Charles W. , Enick, Robert , da Rocha, Sandro R.P.
Institution: Wayne State University , University of Pittsburgh - Main Campus
EPA Project Officer: Bauer, Diana
Project Period: January 1, 2004 through December 31, 2006
Project Amount: $349,967
RFA: Technology for a Sustainable Environment (2003) RFA Text | Recipients Lists
Research Category: Sustainability , Pollution Prevention/Sustainable Development
The development of new materials and a new, environmentally benign binder and template removal technology are proposed with the objectives of reducing the emissions and waste products generated by conventional binder and template removal processes used in the foundry and metal forming industries. The new materials and technology are specifically directed toward application in sand casting and lost foam casting of steel, iron, aluminum, and other metals, and powder injection molding of metals and ceramics.
Our project attacks the problems of emissions and waste products by proposing an alternate binder and template technology where the binder/template material is dissolved into compressed CO2, creating a process stream that can be depressurized to recover both the binder/template and the CO2 in a closed-loop recycling process that produces no emissions.
(i) measurement of equilibrium and transport properties of the binder-CO2 system: we will determined the cloud point of candidate binders in compressed CO2; the swelling behavior of binder and the viscosity of these lower-phase liquids; (ii) wetting and interfacial properties of additive-solid-CO2 interface including interfacial tension of the additive-CO2 and contact angle of the three phase system will be determined; (iii) polymer and surfactant additives required to improve mechanical properties of the mold, template, or green part formed with binder materials will be developed; and (iv) we will also determine the mechanical properties and microstructure of binders.
Upon successful completion of the proposed work, we expect to develop a new class of binder and template materials that will enable the replacement of environmentally undesirable decomposition steps in conventional metal processing operations with a novel environmentally-benign dissolution process using compressed CO2. Furthermore, as outcomes of the proposed research, we expect to provide a range of processing conditions under which dissolution of binders with compressed CO2 can be conducted and dissolution rates can be optimized. Finally, as an outcome of the materials synthesis component of the research, we expect to provide an avenue for obtaining the thermodynamic and mechanical properties needed for each potential application of this new class of binder materials.
Estimated Improvement: If successful, this project will lead toward the replacement of binder and template removal processes in the foundry and metal forming industry that consume large quantities of polymer and organic compounds, thereby eliminating the emissions and waste produced by thermal decomposition and other reactive chemistries used in current practice. Since the foundry and metal forming industries produce very large quantities of castings and parts by sand casting, lost-foam casting, and powder injection molding, the proposed environmentally benign binder and template removal technology would produce a large environmental benefit.