2019.
53. Li, Y., Zhou, L.W., Wang, R.Z., Urban biomass and methods of estimating municipal biomass resources. Renewable Sustain. Energy Rev., 80, 1017–1030, 2017.
54. Perlack, R.D., Wright, L.L., Turhollow, A.F., Graham, R.L., Stokes, B.J., Erbach, D.C., Biomass as feedstock for a bioenergy and bioproducts industry: The technical feasibility of a billion-ton annual supply, Oak Ridge National Laboratory, Tennessee, 2005.
55. Zheng, M., Skelton, R.L., Mackley, M.R., Biodiesel Reaction Screening Using Oscillatory Flow Meso Reactors. Process Saf. Environ. Prot., 85, 5, 365–371, 2007.
56. Demirbas, A., Political, economic and environmental impacts of biofuels: A review. Appl. Energy, 86, S108–S117, 2009.
57. Jeswani, H.K., Chilvers, A., Azapagic, A., Environmental sustainability of biofuels: A review. Proc. R. Soc. A Math. Phys. Eng. Sci., 476, 2243, 20200351, 2020.
58. Directive 2014/23/EU of the European Parliament and of the Council of 26 February 2014 on the award of concession contracts (Text with EEA relevance), in: Brussels Commentary on EU Public Procurement Law, Hart/Nomos, 2018.
59. Panichelli, L., Dauriat, A., Gnansounou, E., Life cycle assessment of soybean-based biodiesel in Argentina for export. Int. J. Life Cycle Assess., 14, 2, 144–159, 2008.
60. Hassan, M.N.A., Jaramillo, P., Griffin, W.M., Life cycle {GHG} emissions from Malaysian oil palm bioenergy development: The impact on transportation sector{\textquotesingle}s energy security. Energy Policy, 39, 5, 2615–2625, 2011.
61. Wang, M., Han, J., Dunn, J.B., Cai, H., Elgowainy, A., Well-to-wheels energy use and greenhouse gas emissions of ethanol from corn, sugarcane and cellulosic biomass for {US} use. Environ. Res. Lett., 7, 4, 45905, 2012.
62. Policy Issues in Biodiversity Conservation 1: The Convention on Biological Diversity, 1999.
63. Scovronick, N. and Wilkinson, P., Health impacts of liquid biofuel production and use: A review. Glob. Environ. Change, 24, 155–164, 2014.
1 *Corresponding author: [email protected]; [email protected]
4
Carbon-Based Catalysts for Biorefinery Processes: Carbon-Based Catalysts for Valorization of Glycerol Waste From Biodiesel Industry
Pawan Rekha1, Lovjeet Singh2*, Brajesh Kumar3, Indu Chauhan4 and Satyendra Prasad Chaurasia1
1Department of Chemistry, Malaviya National Institute of Technology, Jaipur, India
2Department of Chemical Engineering, Malaviya National Institute of Technology, Jaipur, India
3Department of Chemical Engineering, National Institute of Technology Srinagar, India
4Department of Biotechnology, Dr. B. R. Ambedkar National Institute of Technology, Jalandhar, India
Abstract
This chapter will describe the recent developments in the efficient utilization of various carbon-based materials as catalysts for the valorization of glycerol waste from the biodiesel industry. Carbon-based materials are generally prepared from biomass, a renewable feedstock and produced in a large amount from numerous sources such as agricultural wastes, forest residues, and food wastes. Biomass materials consist of cellulose, hemicelluloses, and lignin biopolymer, which act as a carbon source for carbon materials. Since a glycerol glut exists in the global market due to rapid growth in biodiesel production, the utilization of value-added products from glycerol is very important for the competitive market of biodiesel with conventional diesel. This chapter thus discusses the basic principles, mechanisms, and advancement in prominent techniques for glycerol valorization along with synthesis, characterization, and function of different carbon-based catalysts. The future prospects of these carbon materials as catalysts for industrial waste utilization are very promising.
Keywords: Waste to energy, biomass waste, carbon materials, glycerol valorization, biodiesel industry up gradation
4.1 Introduction
With the continuously rising population, rapid industrialization, and improving the standard of living, worldwide energy consumption is increasing at a high rate and projected to become more than double (~1.1 × 1,021 J per hour) by 2050 [1]. Despite enormous efforts to develop alternative energy resources, fossil fuels are estimated to continue as the major energy source for the near future. The widespread utilization of fossil fuels to meet the growing demand for energy has adverse effects due to significant greenhouse gases emission and the exhaustion of these resources. Therefore, the growth and utilization of sustainable resources of energy have become a subject of international importance [2].
Recently, biomass has received tremendous interest from researchers as an alternative feedstock for sustainable and clean energy production [3]. Biodiesel production using biomass is a sustainable approach due to its use as renewable, non-toxic, and biodegradable fuel with a small emission of air pollutants as compared to petroleum-based fuels [4]. Biodiesel is environmentally friendly due to small carbon monoxide and particulate matter emissions and does not release hydrocarbons [5]. The increased production of oxygen in the case of biodiesel leads to complete combustion [5]. The vital feedstock for biodiesel production is animal fat, vegetable oil, or waste cooking oil. The productions of biodiesel have increased drastically for the past few years due to its direct use in diesel engines without modifications [6]. However, the formation of biodiesel by transesterification of animal fats or vegetable oils as a raw feedstock produces approximately 10 wt% glycerol (1,2,3-propanetriol) as a by-product which increases its manufacturing cost [7]. This is bottleneck of the technology. A glycerol glut exists in the global market due to the fast growth in biodiesel production. Therefore, the biodiesel industry needs to produce valuable products from glycerol and make it more competitive with conventional diesel fuel. It is also important from an environmental and economic viewpoint [8].
The continuous increase in biodiesel demand will also generate a huge amount of glycerol and therefore, it needs to be utilized [9]. According to 2011 data, globally the total amount of glycerol produced by the biodiesel industry is 66.2%. In the world, the largest biodiesel-producing countries are the United States and Brazil [10]. In the USA, biodiesel consumption increases from 878 million gallons in 2011 to 1,725 million gallons in 2019. To address this issue, the US Department of Energy declared glycerol as a major building block platform chemical for the future. Therefore, the transformation of glycerol to valuable products is a rapidly growing research area that decreases the expenditure of biodiesel production [7, 11].
The transformation of glycerol into valuable products is essential for the industries because a huge amount of glycerol that is generated through biodiesel production and fermentation of sugars can be utilized judiciously. Moreover, glycerol is a non-hazardous, biodegradable, and bio sustainable compound. Economic and technical analyses indicate that the low cost of glycerol and its multifunctional structure could open a new market for valuable commodity chemicals.
