Catalytic copyrolysis of metal impregnated biomass and plastic with Ni‐based HZSM‐5 catalyst: Synergistic effects, kinetics and product distribution

Abstract

The present work aims to investigate the thermal behavior, kinetics, thermodynamics, and product distribution during copyrolysis of transition metal salt (Ni, Co, Zn, Cu, and Fe)-added biomass and model compounds with low density polyethylene(LDPE) over a Ni-based HZSM-5 catalyst by TGA and fixed bed reactor. The interactions and reaction mechanisms during copyrolysis were evaluated. The influence of Ni-impregnated biomass (C-M) and Nimodified HZSM-5 (Ni/HZ) on the formation of pyrolysis bio-oil from biomass and model compounds and its subsequent effect on catalytic pyrolysis vapor upgrading was discussed. The results indicated that the presence of transition metal decreased the thermal degradation temperature and thermodynamics parameters; maximum decomposition rate, and reaction complexity. Ni/HZ catalyst could further decrease the activation energy, accelerate the reaction rate and change reaction process, and the modified samples/LDPE under copyrolysis with HZSM-5 catalyst presented a more significant effect than Ni/HZ catalyst. Subsequently, the Ea of pine, cellulose and lignin changed from 24.11, 18.29, and 28.68 kJ/mol (CP@Ni/HZ) to 56.04, 69.84, and 16.21 kJ/mol (CP-Ni@HZSM-5), respectively. In addition, Ni could inhibit the depolymerization of cellulose and promoted the formation of char, coke, and lignin derived phenolics. And Ni-impregnated biomass reduced the formation of desired aromatic hydrocarbons, but result in increasing of the char and non-condensable gases. But Ni/HZ catalysts promote the conversion of biomass to target products.

Production of high‐quality bio‐product by pyrolysis of acid/metal modified chickpea husk

“…Pyrolysis of metal impregnated biomass is another technique that has attracted a lot of attention. 19 The catalyst is quite close to the structure of lignocellulosic in this case and is expected to have a direct effect on principal reactions. 20 The use of ex situ catalysts leads to a decrease in liquid production and an increase in gas yield through the cracking of organic molecules.…”

“…In fluidized‐bed reactors, catalysts can also be utilized as bed material. Pyrolysis of metal impregnated biomass is another technique that has attracted a lot of attention 19 . The catalyst is quite close to the structure of lignocellulosic in this case and is expected to have a direct effect on principal reactions 20 …”

“…Solid‐phase analysis showed that metals remained in all chars and had a tendency to form metallic nanoparticles (eg, Cu 0 , Ni 0 , and ZnO) capable of acting as catalysts during the pyrolysis process. He et al 19 used ferric salts (FeCl 3 and Fe(NO 3 ) 3 ) to treat heavy metal‐contaminated biomass to investigate their effect on pyrolytic products and the elimination of heavy metals. According to their findings, the impregnated ferric salts enhanced the bio‐chars' fixed carbon content, fractions of hydrocarbon in bio‐oils, and the evolution of carbon monoxide and hydrogen in gases.…”

Improving the monocyclic aromatic hydrocarbons production from fast pyrolysis of biomass over Fe‐modified ZSM‐5 catalysts

“…[2][3][4][5][6][7] CFP of biomass was proved with high efficiency for the preparation of aromatics. [8][9][10][11][12][13][14] Such pyrolysis reactions are usually executed over ZSM-5 zeolite catalysts during CFP of biomass. [15][16][17][18][19][20][21] For example, Bakar et al reported that ZSM-5 could increase the production of aromatics and light phenols during catalytic pyrolysis of rice husk into bio-oil production.…”

“…CFP of biomass was proved with high efficiency for the preparation of aromatics 8‐14 . Such pyrolysis reactions are usually executed over ZSM‐5 zeolite catalysts during CFP of biomass 15‐21 .…”