Comparative study on characteristics of the bio-oil from microwave-assisted pyrolysis of lignocellulose and triacylglycerol

Breakdown of biomass for energy applications using microwave pyrolysis: A technological review

The agricultural industry faces a permanent increase in waste generation, which is associated with the fast-growing population. Due to the environmental hazards, there is a paramount demand for generating electricity and value-added products from renewable sources. The selection of the conversion method is crucial to develop an eco-friendly, efficient and economically viable energy application. This manuscript investigates the influencing factors that affect the quality and yield of the biochar, bio-oil and biogas during the microwave pyrolysis process, evaluating the biomass nature and diverse combinations of operating conditions. The by-product yield depends on the intrinsic physicochemical properties of biomass. Feedstock with high lignin content is favourable for biochar production, and the breakdown of cellulose and hemicellulose leads to higher syngas formation. Biomass with high volatile matter concentration promotes the generation of bio-oil and biogas. The pyrolysis system's conditions of input power, microwave heating suspector, vacuum, reaction temperature, and the processing chamber geometry were influence factors for optimising the energy recovery. Increased input power and microwave susceptor addition lead to high heating rates, which were beneficial for biogas production, but the excess pyrolysis temperature induce a reduction of bio-oil yield.

Detection and kinetic simulation of animal hair/wool wastes pyrolysis toward high-efficiency and sustainable management

Large quantities of solid wastes are produced each year in the leather industry. The considerable wastes generated exhibit tremendous application potential in terms of renewable energy sources and functional materials. Among them, animal hair/wool wastes possess high carbon content, which can be used sustainably and efficiently by using pyrolysis. Herein, the pyrolysis process of hair/wool wastes was investigated using TG-IR and Py-GC/MS, while the pyrolysis kinetic and thermodynamic were analyzed using "model-free" methods. The results showed that the hair/wool waste pyrolysis process can be divided into three stages: dehydration, devolatilization, and carbonization. The volatile products were mainly phenols (7.42%) and heterocyclic compounds (21.26%), which can be directly used as bio-energy (bio-gases and bio-oil) or converted to other useful chemical products. The kinetic parameters (E_a and A) calculated using the Flynn-Wall-Ozawa, Kissinger-Akahira-Sunose, and Kissinger methods indicated the complexity of the decomposition reactions, which was also confirmed by thermodynamic (ΔH, ΔG, and ΔS) calculation. Some suggestions have also been provided for the preparation of functional biochar with heteroatoms (i.e., N, O, and S) doping. These results not only provide a guide for designing the pyrolysis of hair/wool wastes but can also help develop a potential method to convert the hair/wool wastes into bioenergy to achieve sustainable development of the leather industry.

A Review of Bio-Oil Production through Microwave-Assisted Pyrolysis

The issue of sustainability is a growing concern and has led to many environmentally friendly chemical productions through a great intensification of the use of biomass conversion processes. Thermal conversion of biomass is one of the most attractive tools currently used, and pyrolytic treatments represent the most flexible approach to biomass conversion. In this scenario, microwave-assisted pyrolysis could be a solid choice for the production of multi-chemical mixtures known as bio-oils. Bio-oils could represent a promising new source of high-value species ranging from bioactive chemicals to green solvents. In this review, we have summarized the most recent developments regarding bio-oil production through microwave-induced pyrolytic degradation of biomasses.

The effect of torrefaction and ZSM-5 catalyst for hydrocarbon rich bio-oil production from co-pyrolysis of cellulose and low density polyethylene via microwave-assisted heating

This study aims to investigate the effect of microwave torrefaction and ZSM-5 catalyst for hydrocarbon rich bio-oil production from microwave co-pyrolysis of cellulose and low density polyethylene (LDPE). FTIR analysis displayed remarkable reductions of active hydroxyl and ether groups in microwave torrefied cellulose (MTC), demonstrating that cellulose was less stable than MTC. GC/MS analysis indicated that the hydrocarbons content was ranged from 18.36% to 54.94% in the obtained bio-oils under different conditions, and the maximum hydrocarbons content (54.94%) which also contained the highest aromatic hydrocarbons (19.49%) was obtained from MTC catalytic co-pyrolysis. Microwave-assisted Thermogravimetric analyzer (MW-TGA) analysis showed that MTC catalytic co-pyrolysis apparently shifted the major thermal degradation to a lower temperature area, an evident synergistic effect was observed during MTC catalytic co-pyrolysis. Kinetics study revealed that the activation energy was significantly reduced from 97.87 kJ/mol to 63.86 kJ/mol for co-pyrolysis and MTC catalytic co-pyrolysis, respectively.

Nitrogenous compounds produced by catalytic pyrolysis of cyanobacteria over metal loaded MCM-41 with vaporized methanol

The synergistic effect of methanol and an acidic catalyst promotes the production of nitriles and the enrichment of pentadecanenitrile.