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Biomass utilization could relieve the pressure caused by conventional energy shortage and environmental pollution. Advantage should be taken of the abundant biomass in China as clean energy source to substitute for traditional fossil fuels. At present, flash pyrolysis appears to be an efficient method to produce high yields of liquids that could either be directly used as fuel or converted to other valuable chemicals. Experiments were carried out of pyrolyzing biomass particles in a hot dense fluidized bed of sand to obtain high-quality bio-oil. Among four kinds of biomass species adopted in our experiment, Padauk Wood had the best characteristics in producing bio-oil. GC-MS analysis showed bio-oil to be a complex mixture consisting of many compounds. Furthermore, an integrated model was proposed to reveal how temperature influences biomass pyrolysis. Computation indicated that biomass particles underwent rapid heating before pyrolysis.

In this research, a series of catalysts based on MoSe₂ were synthesized by the hydrothermal method and used for the catalytic hydrogenation of alkali lignin for the first time. For 4wt.% NiSe₂/MoSe₂ catalyst, at 290${}^{\circ }$C, under 2MPa H₂ pressure for 1.5h, the conversion of alkali lignin and the yield of bio-oil reached 96.47% and 93.68%, respectively. In addition, the composition of the product (bio-oil) was analyzed via Fourier transform infrared (FTIR) spectrometry, gas chromatography-mass spectrometry (GC-MS) spectra, and proton nuclear magnetic resonance (¹HNMR) spectra. Finally, our study demonstrated that those MoSe₂-based composite catalysts can effectively degrade the biomass into bio-oil containing valuable chemical products.

The objective of this study was to synthesize carbon-encapsulated bimetallic Co–Mo carbides and sulfides nanoparticles by carbothermal reduction (CR) of molybdenum-promoted biochar and post sulfiding. The bimetallic Co–Mo carbides and sulfides nanoparticles were characterized for physicochemical properties by multiple morphological and structural methods (e.g., SEM, TEM, and XRD). These nanoparticles were tested for catalytic upgrading of the pyrolysis bio-oil from pinewood in a continuous packed-bed reactor. Hydroprocessing experiments were performed at a temperature of 350–425°C, 6.89–12.41 MPa (1,000–1,800 psig) hydrogen pressure with a hydrogen flow rate of 500 ml/min at a liquid hourly space velocity of 0.1–1.0 h⁻¹. The results from sulfided catalytic experiments were compared with CoMo carbide nanoparticles. Sulfided CoMo nanoparticles demonstrated higher catalytic activity and resulted in increased hydrocarbon fraction yields. Moreover, the quality of the hydrocarbon fraction, as determined by the acid value, higher heating value, and water content analyses, also improved.

Crop harvest leaves behind agricultural waste with a significant amount of moisture content. Transporting high moisture agriculture waste biomass to a biorefinery is highly uneconomical. Achieving dry biomass (<10%) for subsequent thermochemical processing such as pyrolysis or gasification is cost-intensive. Hydrothermal liquefaction (HTL) technology is more suited for agricultural waste conversion because it can accept high moisture feedstock to produce biofuels and bioproducts. HTL technology has demonstrated many more advantages over other thermochemical technologies at the laboratory scale. Yet, there is no commercial HTL plant to process agricultural residue or lignocellulosic biomass. Transporting wet biomass and making it HTL-ready are the two significant obstacles to commercializing the HTL technology. Biomass densification may reduce the transportation cost and allow processability at higher biomass loadings. Although densification via pelletization has been reported in the literature, currently, there is no understanding of the influence of densified biomass on HTL product distribution or yield. This chapter covers essential information on HTL technology, reported yields of bioproducts (bio-oil and hydrochar), and the parameters to consider in configuring an HTL-ready feedstock with emphasis on corn stover feedstock densification.

In this paper, the pyrolysis treatment of sewage sludge was studied in a laboratory fixed bed reactor at temperature range of 400~600 ⁰C. Meanwhile, the influences of the final pyrolysis temperature, the heating rate and ZnO additive on the characteristics of the resulting bio-oil were also investigated. The experimental results indicated that more than 35% bio-oil yield was achieved at a pyrolysis temperature range of 500~600 ⁰C and a heating rate of 5 ⁰C/min. Meanwhile, ZnO has some contributions to the vaporation of the volatile in the sewage sludge. Moreover, heavy oxygenated hydrocarbons in the bio-oil are as high as 90%, which should be updated and then reused as fuel.

Appropriate disposal and resourcezation of hyperaccumulator biomass is a problem inhibiting the widespread use of phytoremediation technology. In the present study, the behaviour of heavy metals and bio-oil composition were studied. The major portion of Zn (> 78.2 %) remained in the char while 20.2 % was found in the oil at 450 °C. More than 55.1% fo Cd was vaporized and enrich in the oil. Only 0.06% of Cd were found in the char at 750°C. The major portions of Pb (> 70.3 %) were vaporized during pyrolysis and were found in the oil. Only a minority of Pb (11.2 −18.6 %) was found in the char. Pyrolysis at 550 °C led to the highest yield of alkanes with low-oxygen compounds found in the bio-oil. Pyrolysis at 550 °C can likely offer a valuable processing method for S. plumbizincicola.