High quality liquid fuel production from waste plastics via two-step cracking route in a bottom-up approach using bi-functional Fe/HZSM-5 catalyst. (1st August 2021)

• Record Type: Journal Article
• Authors: Dwivedi, Uma; Naik, S.N.; Pant, K.K.
• Is Part Of: Waste management. Volume 132(2021)
• Page Start: 151
• Page End: 161
• Publication Date: 2021-08-01
• Subjects: Plastic waste -- LDPE/HDPE/PP -- Fe/HZSM-5 -- Bottom-up -- Liquid fuel -- Catalytic Cracking; Hazardous wastes -- Periodicals; Refuse and refuse disposal -- Periodicals; 363.728
• DOI: 10.1016/j.wasman.2021.07.024
• Languages: English
• ISSNs: 0956-053X

Abstract

Graphical abstract: Highlights: High quality liquid fuel from waste plastics via bottom-up cracking approach. Complete degradation of plastics at relatively lower temperature (350 °C) Higher liquid yield (76%) with minimal catalyst to plastic feed ratio (1:30) Liquid product has comparable fuel characteristics with commercial diesel. Abstract: Plastic waste is a serious menace to the world due to its fastest growth rate of ~ 5% per annum and requires efficient technologies for its safe disposal. Plastic liquefaction producing liquid hydrocarbons is an effective way to dispose waste plastics in an eco-friendly manner. In present study, high quality liquid fuel is produced from waste plastics via two-step bottom-up cracking approach. A comparative analysis of liquid products obtained in thermal and catalytic cracking performed at relatively lower temperature (350 °C) with minimal catalyst to plastic feed ratio (1:30) has been studied. Catalytic cracking via two-step bottom-up route provides higher fraction of fuel range hydrocarbons in comparison to the thermal cracking. Catalytic cracking is performed using two different catalysts; HZSM-5 and 5%Fe/HZSM-5 in which later results in higher liquid yield (76 wt%) than former (60 wt%) having comparable fuel characteristics. GC–MS results confirm that liquid product obtained via catalytic cracking contains higher fraction of fuel range hydrocarbons (C6 -C20 ); 66.39% for 5%Fe/HZSM-5 and 47.33% for HZSM-5 which is comparatively higher than that obtained in thermal cracking (27.39%). FT-IR, 1 H and 13 C NMR spectroscopic studies confirm that liquid hydrocarbons obtained via catalytic cracking have comparable chemical characteristics with fuel range hydrocarbons. Physiochemical properties of catalysts are studied using XRD, XPS, BET, FE-SEM, HR-TEM, NH3 -TPD and H2 -TPR techniques and correlated with activity results. Analysis of commercial diesel fuel is also incorporated to compare the fuel characteristics of liquid products.