The Opportunities of Biofuel Coproducts in Value-Added Biocomposite Applications

Abstract

Nowadays, renewable energy resources are gaining more attraction since the future demand for energy and the depleting petroleum resources will soon become an issue to the rapidly-growing global population. In this regard, bioethanol has expanded hugely during the last 10-15 years, especially in the form of corn-based ethanol. In a corn-based ethanol plant, dried distillers’ grain with solubles (DDGS) is also produced as the coproduct as much as ethanol on a weight basis. The surplus amounts of the produced distillers’ grain are beyond its tradition animal feed usage so that the accumulation can become a concern for environmental sustainability of the so-called first-generation bioethanol industry. Moreover, the application of distillers’ grains in new markets is another aspect to be thought of in order to help economic sustainability of the industry. In the present work, the capabilities of DDGS are evaluated for using as a filler and/or reinforcement in producing green biocomposites with a number of bioplastics. The bioplastics used here are partially originated from renewable resources with end-life biodegradability in compost conditions. The focus of this research is to design and engineer material formulations with balanced performance. Extrusion and injection molding techniques have been employed to produce the biocomposites and the performance of the produced materials was evaluated through mechanical, thermomechanical and physical properties. The discussions are augmented with scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). With this approach, biocomposites of DDGS and bioplastics were successfully designed which exhibit acceptable performance such as tensile strength of more than 20 MPa, flexural modulus of more than 1 GPa, impact strength of more than 100 J/m and melt flow index of more than 5 g/10min.