Sustainable Debinding and Recovery of CO2-Soluble Binders

2012-07-04
Dilek Hacıhabiboğlu, Çerağ
Enick, Robert M.
Gulari, Esin
Manke, Charles W.
Metal and ceramic forming applications using conventional binders are associated with a number of environmental problems such as toxic emissions and carcinogenic wastes released from conventional binder removal processes. Here, we examine several materials as possible binder candidates for a sustainable technology wherein the binder can be recovered and recycled by supercritical carbon dioxide. The candidates include an acetylated sugar, beta-D-galactose pentaacetate, and two tert-butyl aromatics, 1,3,5-tri-tert-butylbenzene and 2,4,6-tri-tert-butylphenol, which have significantly high solubility in supercritical carbon dioxide. We have demonstrated high-pressure carbon dioxide debinding of sand molds, each bound with candidate binders, at moderate temperatures and pressures. Practical operating conditions are suggested from the complementary binder-carbon dioxide phase behavior studies. Compared to solvent debinding, these novel binders exhibit rapid dissolution into supercritical CO2 due to enhanced transport properties. With high supercritical CO2 debinding efficiency, these materials are promising for developing more sustainable material forming processes, where toxic emissions and hazardous wastes of conventional debinding techniques can be eliminated, and materials recycling and reuse can be achieved.
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH

Suggestions

Polylactic acid recycling with environmentally benign fluids
Bozcuoğlu, Çağla; Dilek Hacıhabiboğlu, Çerağ; Sezgi, Naime Aslı; Department of Chemical Engineering (2022-2)
In the past few decades, petroleum-based polymers have been replaced by biodegradable polymers since they bring about environmental problems. Polylactic acid (PLA) is a good candidate for this replacement due to its biocompatible and biodegradable nature and favorable mechanical and thermal properties. Due to the increase in usage and demand, there will be a PLA waste problem in the near future. Although PLA is classified as a biodegradable polymer, only a few microorganisms, which are not present in all so...
Development of graphene oxide based aerogels
Doğan, Öznur; Bat, Erhan; Department of Chemical Engineering (2017)
Owing to their large surface area, high hydrophobicity and porous structure, graphene oxide based aerogels have been proposed as feasible and economic solutions for the increasing water pollution caused by crude oils, petroleum products and toxic organic solvents. In this study, graphene oxide based aerogels were prepared via two different routes. In the first route, random copolymers of glycidyl methacrylate and styrene were used as crosslinkers in the aerogel. In the second route, 1,3-diaminopropane was u...
Corrosion Resistance Studies of Austenitic Stainless Steel Grades in Molten Zinc-Aluminum Alloy Galvanizing Bath
Loto, Roland Tolulope; Ozcan, Emre (Springer Science and Business Media LLC, 2016-06-01)
The corrosion inhibition performance and mechanical behavior of galvanized and heat-treated four newly developed austenitic stainless steel grades and type 316L austenitic stainless steel for application as sink rolls in galvanizing baths of 0.14-0.21 wt.% aluminum was investigated and compared through immersion corrosion test to determine the weight loss between 168 and 504 h, tensile test, and Charpy impact test. The delta ferrite content of the test samples was observed and estimated through optical micr...
Electrochemical Performance of (MgCoNiZn)(1-x)LixO High-Entropy Oxides in Lithium-Ion Batteries
Lökçü, Ersu; Toparlı, Çiğdem; Anık, Mustafa (2020-05-01)
High-entropy oxides (HEOs), which are a new class of single-phase solid solution materials, have recently attracted significant attention as an anode material for lithium-ion batteries (LIBs). In this study, (MgCoNiZn)(1-x)LixO (x = 0.05, 0.15, 0.25, and 0.35) HEOs were synthesized and their electrochemical performances as the anode material were observed in LIBs. X-ray photoelectron spectroscopy (XPS) analysis showed that the increase in the lithium cation concentration causes generation of more oxygen vac...
Polystyrene / boron nitride nanotube composites: synthesis, processing and characterization
Balık, Erdem; Bayram, Göknur; Sezgi, Naime Aslı; Department of Chemical Engineering (2015)
In recent years, boron nitride nanotubes (BNNTs) have been added to polystyrene (PS) which is a widely used thermoplastic polymer in order to improve its thermal and mechanical properties. Solution mixing and melt blending techniques are commonly used methods to prepare polymer-boron nitride nanotube (BNNT) composites. However, these two composite preparation methods have a common problem about the dispersion of fillers in the polymer matrix. In this study, PS-BNNT composites were prepared using masterbatch...
Citation Formats
Ç. Dilek Hacıhabiboğlu, R. M. Enick, E. Gulari, and C. W. Manke, “Sustainable Debinding and Recovery of CO2-Soluble Binders,” INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH, pp. 9101–9105, 2012, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/47108.