Zhi-bo Zhang

Catalytic fast pyrolysis of cellulose and biomass to produce levoglucosenone using magnetic SO42−/TiO2–Fe3O4

Magnetic superacid (SO4(2-)/TiO2-Fe3O4) was prepared for catalytic fast pyrolysis of cellulose and poplar wood to produce levoglucosenone (LGO). Its catalytic activity was evaluated via pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) experiments, and compared with the non-magnetic SO4(2-)/TiO2, phosphoric acid (H3PO4) and sulfur acid (H2SO4) catalysts. Moreover, the LGO yield was quantitatively determined. The results indicated that the magnetic SO4(2-)/TiO2-Fe3O4 was effective to selectively produce LGO from both cellulose and poplar wood. Its catalytic capability was a little better than the non-magnetic SO4(2-)/TiO2 and H3PO4, and much better than the H2SO4. The maximal LGO yields from both cellulose and poplar wood were obtained at 300 °C with the feedstock/catalyst ratio of 1/1, reaching as high as 15.43 wt% from cellulose and 7.06 wt% from poplar wood, respectively.

Overview of Chemical Characterization of Biomass Fast Pyrolysis Oils

Fast pyrolysis of biomass to produce bio-oil is one of the most promising technologies to utilize lignocellulosic biomass. Liquid bio-oil covers many potential application fields, to be used a fuel or a source for chemical extraction and production. Hence, it is necessary to understand the chemical properties of bio-oil. This review concentrates on the elemental and chemical properties of bio-oil, and also discusses the analysis and separation methods.

Preparation and Characterization of Briquette Fuel from Biomass-Fired Fly Ash

In many of the current biomass-fired power plants, the fly ash usually contains abundant combustible char, due to the in-sufficient burning. In this study, a new idea was proposed to prepare briquette fuel using the fly ash. Experiments were conducted to produce six briquette fuels from the fly ash added with the composite binder and using a lab-scale briquetting machine. The mechanical strength of the six briquette fuels and their burning-out residues was measured, to reveal the effects of the composite binder on preparation and characteristics of the briquette fuel.

Production of Phenolic Compounds from Low Temperature Catalytic Fast Pyrolysis of Biomass with Activated Carbon

Activated carbon (AC) was reported as a promising catalyst to selectively produce phenolic compounds from biomass using the micro-wave assisted catalytic pyrolysis technique. In order to evaluate the catalytic performance of the AC under the traditional fast pyrolysis process, analytical pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) technique was applied for the catalytic fast pyrolysis of biomass mixed with the AC. Polar wood was selected as the feedstock, and experiments were conducted to reveal the AC-catalyzed poplar wood pyrolysis behavior and product distribution. The results indicated that the AC was also effective for the phenolics production in the traditional fast pyrolysis process at 350 °C. It could promote the formation of phenolic compounds, and inhibit most of the other pyrolytic products. The maximal phenolics yield was obtained at the biomass to catalyst ratio of 1:4, with the peak area% over 50%.

Thermogravimetric Analysis of Raw and Demineralized Biomass Materials

Thermogravimetric analysis (TGA) was employed to study the pyrolysis characteristics of two biomass materials (poplar and pine wood) and their demineralized samples under nitrogen atmosphere. Based on the experimental results, the pyrolysis kinetics were calculated. The results indicated that the starting and ending time of devolatilization were delayed after the demineralization of the biomass. For all the materials, the temperature of the maximum weight loss rate occurred at around 390°C, while the maximum values increased a little after demineralization. The pine wood was more difficult to decompose than the poplar wood, due to its high activation energy values. In addition, after demineralization, the activation energy values of the pine wood decreased, while the values of the poplar wood were not significantly changed.

Overview of Methods to Remove Solid Particles from Biomass Fast Pyrolysis Oils

Fast pyrolysis of biomass to produce bio-oil is an important technology to utilize lignocellulosic biomass materials, as it offers a convenient way to convert solid biomass mainly into the liquid bio-oil. Bio-oil is regard as a promising candidate of petroleum fuels, but it is a low-grade liquid fuel and difficult to be used in various thermal devices, due to the presence of many undesirable components. One of the undesirable components is the solid particles, resulting from insufficient separation of the pyrolytic products. The solid particles will bring many negative effects to the storage and combustion of bio-oil, and thus, should be removed. This paper reviews the recent progress on the removal of solid particles, through the filtration of liquid bio-oil or pyrolysis vapors.

The Drying Characteristic of Biomass with High Moisture Content

This paper presents the drying characteristics of rice husk and cornstalk with high moisture content at fixed temperatures. Experiments were performed in an oven drier, to reveal to the effects of initial moisture content, bed thickness and drying temperature on the biomass drying characteristics. The results indicated that the drying time was decreased as the rising of the drying temperature, and increased along with the initial moisture content and bed thickness. Moreover, the risk husk was easy to be dried than the cornstalk.