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Abstract Herein high-strength composites are prepared from elemental sulfur, sunflower oil, and wastewater sludge. Fats extracted from dissolved air flotation (DAF) solids were reacted with elemental sulfur to yield compositeDAFS(10 wt% DAF fats and 90 wt% sulfur). Additional composites were prepared from DAF fat, sunflower oil and sulfur to giveSunDAFx(x = wt% sulfur, varied from 85–90%). The composites were characterized by spectroscopic, thermal, and mechanical methods. FT-IR spectra revealed a notable peak at 798 cm–1indicating a C–S stretch inDAFS,SunDAF90, andSunDAF85indicating successful crosslinking of polymeric sulfur with olefin units. SEM/EDX analysis revealed homogenous distribution of carbon, oxygen, and sulfur inSunDAF90andSunDAF85. The percent crystallinity exhibited byDAFS(37%),SunDAF90(39%), andSunDAF85(45%) was observed to be slightly lower than that of previous composites prepared from elemental sulfur and fats and oils.DAFSandSunDAFxdisplayed compressive strengths (26.4–38.7 MPa) of up to 227% above that required (17 MPa) of ordinary Portland cement for residential building foundations. The composite decomposition temperatures ranged from 211 to 219 °C, with glass transition temperatures of − 37 °C to − 39 °C. These composites thus provide a potential route to reclaim wastewater organics for use in value-added structural materials having mechanical properties competitive with those of commercial products.
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Green and Atom Economical Route to High Compressive Strength Lignin Oil-Sulfur Composites
Abstract Lignin is the most abundant natural source of aromatics but remains underutilized. Elemental sulfur is a plentiful by-product of fossil fuel refining. Herein we report a strategy for preparing a durable composite by the one-pot reaction of elemental sulfur and lignin oil comprising lower molecular weight lignin derivatives. A lignin oil-sulfur composite (LOS90) was prepared by reacting 10 wt. % lignin oil with 90 wt. % elemental sulfur. The composite could be remelted and reshaped over several cycles without loss of properties. Results from the study showed thatLOS90has properties competitive with or exceeding values for commercial ordinary Portland cement and brick formulations. For example,LOS90displayed impressive compressive strength (22.1 MPa) and flexural strength (5.7 MPa).LOS90is prepared entirely from waste materials with 98.5% atom economy of composite synthesis, a lowEfactor of 0.057, and lignin char as the only waste product of the process for its preparation. These results suggest the potential applications of lignin and waste sulfur in the continuous efforts to develop more recyclable and sustainable materials.
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- Award ID(s):
- 2203669
- PAR ID:
- 10503226
- Publisher / Repository:
- Springer Science + Business Media
- Date Published:
- Journal Name:
- Journal of Polymers and the Environment
- Volume:
- 32
- Issue:
- 10
- ISSN:
- 1566-2543
- Format(s):
- Medium: X Size: p. 4842-4854
- Size(s):
- p. 4842-4854
- Sponsoring Org:
- National Science Foundation
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