Catalytic co-pyrolysis of oil sludge and biomass over ZSM-5 for production of aromatic platform chemicals

Preparation of pyrolysis products by catalytic pyrolysis of poplar: Application of biochar in antibiotic wastewater treatment

Poplar waste is acted as feedstock to produce renewable biofuel and green chemical by catalytic pyrolysis using ferric nitrate and zinc chloride as additive. The additive contributes to the generation of furfural in bio-oil. Additive promotes the generation of H2 and inhibits the generation of CO with bio-gas heating value of 12.16 MJ (Nm3)-1. Biochar exists ZnO and Fe3O4 with large surface area, which could be used as absorbent and photocatalyst for tetracycline and ciprofloxacin removal. The tetracycline and ciprofloxacin adsorption amount of biochar are 316.41 and 255.23 mg g-1 respectively. While the photocatalytic degradation removal of the tetracycline and ciprofloxacin is close to 100%. The adsorption and photocatalytic degradation mechanism are investigate and analyzed using the density functional theory and electron paramagnetic resonance analysis. Biochar can be quickly recycled and regenerated after use. Besides, biochar can be used in lithium ion battery industry for energy storage, which specific capacity is 535 mAh g-1.

A Review on Catalytic Fast Co-Pyrolysis Using Analytical Py-GC/MS

Py-GC/MS combines pyrolysis with analytical tools of gas chromatography (GC) and mass spectrometry (MS) and is a quick and highly effective method to analyse the volatiles generated from small amounts of feeds. The review focuses on using zeolites and other catalysts in the fast co-pyrolysis of various feedstocks, including biomass wastes (plants and animals) and municipal waste materials, to improve the yield of specific volatile products. The utilisation of zeolite catalysts, including HZSM-5 and nMFI, results in a synergistic reduction of oxygen and an increase in the hydrocarbon content of pyrolysis products. The literature works also indicate HZSM-5 produced the most bio-oil and had the least coke deposition among the zeolites tested. Other catalysts, such as metals and metal oxides, and feedstocks that act as catalysts (self-catalysis), such as red mud and oil shale, are also discussed in the review. Combining catalysts, such as metal oxides and HZSM-5, further improves the yields of aromatics during co-pyrolysis. The review highlights the need for further research on the kinetics of the processes, optimisation of feed-to-catalyst ratios, and stability of catalysts and products.

Investigation of Catalytic Co-Pyrolysis Characteristics and Synergistic Effect of Oily Sludge and Walnut Shell

The co-pyrolysis of oily sludge and walnut shell is a reliable method for solid waste treatment and waste recycling. In this paper, a thermogravimetric analysis was used to study the thermodynamics and synergy effect of oily sludge (OS) and walnut shell (WS) at four heating rates (10, 20, 30, and 40 °C/min) in the temperature range from 50-850 °C. Two model-free methods (FWO and KAS) were used to calculate the activation energy. The results showed that the heating rate had no significant effect on the pyrolysis process. The addition of walnut shell improved the pyrolysis process of the samples. Mixture 1OS3WS had a synergy effect, while other blends showed an inhibitory effect. The synergy effect of co-pyrolysis was strongest when the mass ratio of oily sludge was 25%. The activation energy of the Zn-ZSM-5/25 catalyst was the lowest, and the residual substances were the least, indicating that the Zn-ZSM-5/25 was beneficial to the co-pyrolysis of oily sludge and walnut shell. The analysis of catalytic pyrolysis products by Py-GC/MS found that co-pyrolysis was beneficial to the generation of aromatic hydrocarbons. This study provided a method for the resource utilization of hazardous waste and biomass waste, which was conducive to the production of aromatic chemicals with added value while reducing environmental pollution.

Effects of microwave and plastic content on the sulfur migration during co-pyrolysis of biomass and plastic

In order to reduce the risks of sulfur-containing contaminants present in biofuels, the effects of microwave and content of hydrogen donor on the cracking of C-S bonds and the migration of sulfur were studied by co-pyrolysis of biomass and plastic. The synergistic mechanism of microwave and hydrogen donor was explored from the perspective of deducing the evolution of sulfur-containing compounds based on microwave thermogravimetric analysis. By combining temperature-weight curves, it was found that microwaves and hydrogen radicals promoted the cracking of sulfur-containing compounds and increased the mass loss of biomass during pyrolysis. The mixing ratio of hydrogen donor (plastic) was the key parameter resulting in the removal of sulfur from oil. By adjusting the mixing ratio, the yield of co-pyrolyzed oil was three times higher than that of cow dung pyrolysis alone and the relative removal rate of sulfur reached 73.67%. The relative content of sulfur in the oil was reduced by 73.77% due to the escape of sulfur-containing gases (H₂S, COS and C₂H₅SH) and the formation of sulfate crystals in the char. Microwave selectively heated sulfur-containing organics and hydrogen radicals stimulated the breaking of C-S bonds, which improved the cracking efficiency of the oil. This breaking will provide a theoretical and technological reference for the environmentally friendly treatment of biomass and biofuels.

On-Line Thermally Induced Evolved Gas Analysis: An Update-Part 2: EGA-FTIR

The on-line thermally induced evolved gas analysis (OLTI-EGA) is widely applied in many different fields. Aimed to update the applications, our group has systematically collected and published examples of EGA characterizations. Following the recently published review on EGA-MS applications, this second part reviews the latest applications of Evolved Gas Analysis performed by on-line coupling heating devices to infrared spectrometers (EGA-FTIR). The selected 2019, 2020, 2021 and early 2022 references are collected and briefly described in this review; these are useful to help researchers to easily find applications that are sometimes difficult to locate.

Microwave catalytic co-pyrolysis of chlorella vulgaris and oily sludge: Characteristics and bio-oil analysis

Co-pyrolysis of Chlorella vulgaris (CV) and Oily sludge (OS) under different mixing ratios were investigated by microwave furnace. NiO, activated carbon (AC) and their 1:1 compound (N1A1) with different additions (5%, 10%, 15% and 20%) were selected as microwave additives to study the effects on optimum mixing ratio of co-pyrolysis. The results indicated that mixing ratio of CV/OS = 1:1 (C1O1) was optimum for co-pyrolysis. Besides, 10% AC was optimal on improving pyrolysis characteristics of the C1O1 group. The most significant synergistic interaction of NiO and AC occurred in the 10% N1A1 group. Moreover, hydrocarbons in bio-oil of the C1O1 group increased by 31.84% compared with theoretical values, while nitrogenous, oxygenated compounds decreased by 74.18% and 19.01%. Addition of 10% N1A1 in the C1O1 group increased aliphatic hydrocarbons by 22.44%, and decreased nitrogenous, oxygenated compounds by 41.79% and 36.58%. Overall, 10% N1A1 was conducive for the C1O1 group to obtain high-quality bio-oil.