CaO catalysts

CaO catalysts

Accepted Manuscript Title: Comparision of catalytic upgrading of biomass fast pyrolysis vapors over CaO and Fe(ш)/CaO catalysts Author: Xiaodong Zhang...

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Accepted Manuscript Title: Comparision of catalytic upgrading of biomass fast pyrolysis vapors over CaO and Fe(ш)/CaO catalysts Author: Xiaodong Zhang Laizhi Sun Lei Chen Xinping Xie Baofeng Zhao Hongyu Si Guangfan Meng PII: DOI: Reference:

S0165-2370(14)00126-0 http://dx.doi.org/doi:10.1016/j.jaap.2014.05.020 JAAP 3212

To appear in:

J. Anal. Appl. Pyrolysis

Received date: Revised date: Accepted date:

4-3-2014 23-5-2014 28-5-2014

Please cite this article as: X. Zhang, L. Sun, L. Chen, X. Xie, B. Zhao, H. Si, G. Meng, Comparision of catalytic upgrading of biomass fast pyrolysis vapors over CaO and Fe(shcy)/CaO catalysts, Journal of Analytical and Applied Pyrolysis (2014), http://dx.doi.org/10.1016/j.jaap.2014.05.020 This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.

Comparision of catalytic upgrading of biomass fast pyrolysis

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vapors over CaO and Fe(ш)/CaO catalysts

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Xiaodong Zhang∗,ϑ, Laizhi Sunϑ, Lei Chen, Xinping Xie , Baofeng Zhao, Hongyu Si,

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Guangfan Meng

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Key laboratory for biomass gasification technology of Shandong province,

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Energy Research Institute of Shandong Academy of Sciences, Jinan 250014, China

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Abstract

The CaO and Fe(ш)/CaO catalysts were prepared and employed for catalytic

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upgrading of biomass fast pyrolysis vapors by pyrolysis-gas chromatography/mass

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spectrometry instrument (Py-GC/MS). It was found that the Fe(ш)/CaO catalyst was

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effective in upgrading the biomass fast pyrolysis vapors by reducing the amounts of

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oxygenated compounds. The Fe(ш)/CaO catalyst displayed good capabilities to

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transform the heavy phenols to light phenols without the methoxyl group and

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unsaturated C-C bonds on the side chain. Moreover, the catalyst completely eliminated

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the acids and significantly decreased the yields of aldehydes and ketones. The yields of

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furans, light and aromatic hydrocarbons were greatly increased. Based on the results of

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catalyst characterization and activity experiments, it seems that the higher activity of

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the Fe(ш)/CaO catalyst is related to the synergistic effect between Fe and CaO

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support, and the Ca2Fe2O5 phase formed in the catalyst might protect the CaO support

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and inhibit the Fe sintering in the upgrading reactions. ∗

Corresponding author, E-mail: [email protected] .Tel:+86 531 85599028.  The two authors contributed equally to this work.

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Keywords: Biomass; upgrading; Fast pyrolysis vapors; CaO; Fe(ш)/CaO catalyst.

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1. Introduction Fast pyrolysis of biomass to bio-oils is one of the most prospective technologies for

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the utilization of biomass resources, and it has attracted extensive attentions in recent

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years [1-4]. The bio-oils are renewable liquid fuels and can also be the source of

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valuable chemicals [5, 6].

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However, the direct use of bio-oils is difficult due to its complex composition. The

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components, such as acids, aldehydes, ketones and unsaturated compounds, result in

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high viscosity, corrosiveness, low heat value, instability and other undesired properties

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of the bio-oils [7, 8]. Therefore, it is necessary to upgrade the bio-oils by decreasing the

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amount of undesired compounds and converting them to useful compounds. Two

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methods have been developed for upgrading the bio-oils. The first method is catalytic

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hydrotreating with hydrogen under high pressure [9-12]. The second method is catalytic

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cracking under atmospheric pressure [13-16]. For the second method, no hydrogen is

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required, and the reaction is operated under atmospheric pressure, which can reduce the

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operating cost.

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Due to its nontoxicity and low cost, CaO is widely used as CO2 sorbents and tar

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cracking catalyst in biomass gasification [17-19]. However, there are some literatures

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reported that the base materials, such as CaO, dolomite and limestone, had good activity

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in catalytic cracking the bio-oils to liquid fuels. Chen et al. found that the application of

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CaO catalyst increased the yields of hydrogen and pyrolytic gases in the catalytic

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pyrolysis of sawdust [20]. Ding et al. showed that the CaO catalyst could convert the

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acids to hydrocarbons by the decarboxylation reactions [21]. So CaO may be a good

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catalyst in the catalytic upgrading of bio-oils. Furthermore, transition metal-based

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catalysts, such as Fe,Zn and Cu, have shown potential ability in the catalytic

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upgrading of bio-oils [22-24]. Lu et al. reported that ZnO was found to be a mild

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catalyst and the use of Fe2O3 resulted in the formation of various hydrocarbons [23].

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Torri et al. investigated the catalytic pyrolysis of pine sawdust over various metal oxides

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(Fe2O3, CuO and ZnO) and found that the heavy compounds were reduced with a

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limited decrease in the bio-oil yield after catalysis [24].

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Although CaO may be a good catalyst for the upgrading of bio-oils, it is easily

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deactivated in the pyrolysis processes. Therefore, in this work, we aimed to design a

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novel catalyst to prevent the CaO deactivation by loading Fe on the CaO support as a

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protection. Then, the Fe(ш)/CaO catalyst was prepared by the impregnation method and

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characterized by the Brunauer-Emmett-Teller (BET), X-ray diffraction (XRD) and CO2

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temperature-programmed desorption experiment (CO2-TPD). The effects of Fe(ш)/CaO

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catalyst on the distribution of pyrolytic products were studied by Py-GC/MS

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experiments. By combining the product analyses and catalyst characterization results,

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the catalytic mechanism of Fe(ш)/CaO catalyst in upgrading of biomass fast pyrolysis

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vapors was discussed.

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2. Materials and Methods

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2.1. Materials

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Sawdust was used as feed material and its size was 0.2-0.3 mm. The ultimate and

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proximate analyses of sawdust are listed in Table 1.

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2.2. Catalysts preparation

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The Fe(ш)/CaO catalyst with 5wt% iron was prepared by the impregnation method.

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The stoichiometric quantities of iron nitrate (Fe(NO3)3·9H2O) were dissolved in distilled

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water. Then CaO was added and stirred to obtain a suspension. After being dried at 110

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was dried at 120 oC for 10 h and then calcined at 900oC for 4 h.

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2.3. Catalyst characterization

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C for 12 h, the powders were calcined in air at 900 oC for 4 h. Before CaO was used, it

Surface areas of the samples were measured by a BET nitrogen adsorption method at

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-196 oC using a JW-BK132F machine. Total pore volumes were measured by single

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point adsorption.

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XRD was conducted on Rigaku D/max-rB by using Cu Ka radiation. The anode was

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operated at 40 kV and 40 mA. The 2θ angles were scanned from 20 to 80o. CO2-TPD experiments were performed on Finesorb-3010c. Before CO2-TPD

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experiment, all samples were first treated in Ar at 900 oC for 1 h and then cooled down

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to 550 oC. Then CO2 was introduced into the flow system at 550 oC for 1 h, after that

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the samples were cooled down to 100 oC. The TPD spectra were recorded at a

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temperature rising rate of 10 oC/min from 100 oC to 900 oC in Ar. CO2 desorbed from

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the samples was detected and recorded as a function of temperature.

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2.4. Catalytic reaction

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Py-GC/MS experiments were performed in the CDS Pyroprobe 5200HP pyrolyser

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(Chemical Data Systems) connected with a gas chromatography/mass spectrometry

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(7890/5975C, Agilent). The schematic of Py-GC/MS used in the experiments is shown

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in Figure.1. Fast pyrolysis of sawdust was achieved by the pyrolyser, and the pyrolysis

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vapors were directly transferred to the GC/MS and analyzed by it.

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During the experiments, the ratio of catalyst to sawdust was 1, and the pyrolysis tube

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was filled with 0.5 mg of sawdust and 0.5 mg of catalyst. The pyrolysis temperature

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was set at 800 oC with a heating rate of 20 oC/ms and held for 25 s. A helium carrier gas

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of 30 ml/min flow rate was used to purge the pyrolysis chamber. The actual biomass

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pyrolysis temperature would be lower than the set value due to the poor thermal

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conductivity of biomass materials. It was reported that the actual pyrolysis temperature

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may be about 700 oC [22]. Moreover, some literatures reported that different heating

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rates and final pyrolysis temperatures result in the change of the yields and

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compositions of the pyrolysis products [7, 14 and 15]. Onay Ozlem found that the yield

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of oil increased with the increase of pyrolysis temperature, and the higher heating rate

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could break the heat and mass transfer limitation in the pyrolysis, resulting in the

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maximum oil yield [14].

The chromatographic separation of the volatile products was performed using an

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Agilent HP-5 capillary column. Helium (99.999%) was used as the carrier gas and the

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inject split rato was 100:1 split ratio. The oven temperature was programmed from 40

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C to 180 oC with the heating rate of 4 oC /min, and then to 280 oC with the heating rate

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of 10 oC /min. The temperature of the GC/MS interface was held at 280 oC. The mass

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spectra were obtained from m/z 50 to 400. The chromatographic peaks were identified

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according to the NIST library. The experiments were conducted at least three times for

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each sample to confirm the reproducibility. For each identified product, the average

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values of the peak area were calculated and used.

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Due to the complex products and the lack of commercially available standards for

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them, the GC/MS technique cannot give the direct quantitative analysis of the

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compounds. However, the chromatographic peak area of a compound is considered

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linear with its quantity. Therefore, for each product, its average peak area obtained with

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different catalysts can be compared to reveal the changing of its yields [25-27].

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3. Results and discussions

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3.1 Catalyst characterization

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3.1.1 Textural properties of the catalysts

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Table 2 summarizes the  textural of properties of the catalysts. Compared to the CaO

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catalyst, the surface area of the Fe(ш)/CaO catalyst decreases and the pore volume

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remains unchanged.

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3.1.2. XRD patterns of the catalysts

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XRD patterns of the CaO and Fe(ш)/CaO catalysts are presented in Figure 2.

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According to Figure 2, the CaO catalyst only shows the characteristic peaks of CaO.

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When Fe is loaded on the CaO support, the Ca2Fe2O5 phase is formed in the Fe(ш)/CaO

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catalyst. It indicates that Fe strongly reacts with the CaO support and results in the

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formation of Ca2Fe2O5 phase.

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3.1.3. CO2-TPD patterns of the catalysts Fig. 3 shows the CO2-TPD patterns of the catalysts. It can be seen that the CaO

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catalyst has a desorption peak at nearly 680 oC. For the Fe(ш)/CaO catalyst, there is

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also a desorption peak at 700 oC. Moreover, compared to the CaO catalyst, the CO2

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desorption intensity of the Fe(ш)/CaO catalyst is higher, which indicates that the

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basicity of the Fe(ш)/CaO catalyst is stronger than that of the CaO catalyst. It can be

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attributed to the formation of Ca(OH)2 phase during the preparation processes. This was

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confirmed by the Ca(OH) 2 phases presented in XRD patterns of the Fe(ш)/CaO catalyst

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(shown in Fig. 2).

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3.2. Catalytic performances

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3.2.1. Catalytic effects on the overall distribution of the pyrolytic products

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Py-GC/MS experiments were conducted to investigate the effects of CaO and

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Fe(ш)/CaO catalysts on the upgrading of biomass fast pyrolysis vapors. Main pyrolytic

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products from fast pyrolysis of sawdust without catalysts are listed in Table 3. Fig.4

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shows the total ion chromatograms of sawdust pyrolysis from non-catalytic and

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catalytic experiments. The effects of those catalysts on the yields and compositions of

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pyrolytic products are conspicuous. In order to clearly show the changes of the yields

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and compositions of the products, they are classified into six groups and the overall

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distribution of them is present in Fig.5. Compared to the results of fast pyrolysis of

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sawdust without catalysts, the total yields of phenols, acids, aldehydes and ketones were

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decreased, while the total yields of furans, light and aromatic hydrocarbons were

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increased by the catalysts. In the following several sections, the comparison of catalytic effects of CaO and

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Fe(ш)/CaO catalysts on the yields and compositions of the specific products will be

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discussed in detail.

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3.2.2. Catalytic effects on the phenolic compounds

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The catalytic effects on the yields and compositions of phenolic compounds are shown

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in Fig.6. According to the functional groups of the phenolic compounds, they are

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classified into two categories [28]. The first category is the phenolic compounds that

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contain no methoxyl group and no unsaturated C-C bonds on the side chain, named as

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light phenols. These compounds were all increased with the application of the CaO and

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Fe(ш)/CaO catalysts. Furthermore, some light phenols, such as 2-methyl-phenol and 3-

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methyl-phenol, were formed after catalysis. The second category is the phenolic

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compounds that contain methoxyl group or unsaturated C-C bonds on the side chain,

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named as heavy phenols. They were completely eliminated with the use of the CaO and

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Fe(ш)/CaO catalysts.

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On the basis of the above results, it can be seen that with the application of CaO and

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Fe(ш)/CaO catalysts, the light phenols were greatly increased, while the heavy phenols

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were completely eliminated. Lu et al. found that CaO reduced the levels of phenols and

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increased the formation of cyclopentanones, hydrocarbons and several light compounds

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[23]. Therefore, we can conclude that the CaO and Fe(ш)/CaO catalysts have good

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capabilities in upgrading of biomass fast pyrolysis vapors by removing the methoxyl

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group and hydrotreating the unsaturated C-C bonds on the side chain.

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3.2.3. Catalytic effects on the acids, aldehydes and ketones

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It is well known that the carbonyls, such as acids, aldehydes and ketones, negatively

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affect the fuel properties of bio-oils [7, 8]. The acids increase the corrosion of bio-oil

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and cause problems in the engines during combustion. Aldehydes and ketones are

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mainly responsible for the ageing reactions and result in the instability of bio-oils.

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The catalytic effects on the yields and compositions of acids are shown in Fig.5. As

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can be seen from Fig.5, the acids were completely eliminated in the presence of the CaO

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and Fe(ш)/CaO catalysts. It has been reported that the acids can be converted to

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hydrocarbons through the neutralization and catalytic cracking reactions [7, 21, and 28].

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Therefore, the elimination of acids from the pyrolytic products may be due to the

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basicity and catalytic cracking ability of the CaO and Fe(ш)/CaO catalysts.

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The catalytic effects on the yields  and compositions of aldehydes and ketones are

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shown in Fig.7 and Fig.8. According to Fig.7, the yields and kinds of aldehydes were

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obviously decreased after catalysis. The yields of aldehydes contain hydroxyl and

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methoxyl group, such as 4-methyl-2, 5-dimethoxybenzaldehyde and 4-hydroxy-3, 5-

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dimethoxybenzaldehyde, were completely eliminated from the pyrolytic products.

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Moreover, compared to that of CaO catalyst, more aldehydes were deoxygenated with

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Fe(ш)/CaO catalyst. In the case of the ketones, as shown in Fig.8, the compounds that

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contained hydroxyl and methoxyl group, such as 1-(4-hydroxy-3, 5-dimethoxyphenyl)-

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ethanone, were completely eliminated after catalysis. Moreover, compared with the

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results of non-catalytic experiments, it should be noted that the kinds of ketones were

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increased by the CaO catalyst, but no ketone was detected by the Fe(ш)/CaO catalyst.

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This indicated that the introduction of Fe greatly improved the decarbonylation ability

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of the CaO catalyst.

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In conclusion, compared to the CaO catalyst, the Fe(ш)/CaO catalyst displayed better

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activity in decreasing the amounts of carbonyl compounds, mainly by removing the

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carbonyl, methoxyl and hydroxyl group.

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3.2.4. Catalytic effects on the furans, light and aromatic hydrocarbons

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Fig.9 shows the catalytic effects on the furans products. According to Fig.9, it is

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obvious that the yields of furans were increased after catalysis, and furfural was

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eliminated by the CaO and Fe(ш)/CaO catalysts.

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The catalytic effects on the yields and compositions of light and aromatic

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hydrocarbons are present in Fig.10 and Fig.11. The increase in the yields of

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hydrocarbons can improve the heat values of bio-oil. As can be seen from Fig.10 and

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Fig.11, the non-catalytic fast pyrolysis of sawdust only generated a small amount of

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light and aromatic hydrocarbons. After catalysis, the yields and kinds of light and

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aromatic hydrocarbons were significantly increased. In addition, the Fe(ш)/CaO

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catalyst performed much better activity than the CaO catalyst. There are many

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literatures reported that the formation of hydrocarbons could be achieved by the

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conversion of acids, aldehyde and ketones [28, 29]. Therefore, the increase in the yields

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and compositions of hydrocarbons indicates that the Fe(ш)/CaO catalyst can effectively

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promote the decarboxylation and decarbonylation reactions, resulting in transforming

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oxygenated compounds into hydrocarbons. The results obtained are well accordance

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with the decrease of acids, aldehyde and ketones (shown in Fig.5, 7, 8).

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3.3. Catalytic mechanism of the Fe(ш)/CaO catalyst in upgrading of biomass fast

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pyrolysis vapors

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Based on the above results, it can be concluded that the Fe(ш)/CaO catalyst behaves

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better ability in upgrading of biomass fast pyrolysis vapors than the CaO catalyst. The

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Fe(ш)/CaO catalyst can reduce the oxygen content of bio-oils by removing the

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carbonyl, methoxyl and hydroxyl group, and it was especially effective in decreasing

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the amounts of carbonyl compounds, such as acids, aldehydes and ketones. According

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to the reported literatures [20-24], Fe2O3 and CaO were capable of reducing the

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carbonyl compounds and transforming them to various hydrocarbons due to their

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cracking ability and basicity nature. The two catalysts promoted the demethoxylation

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and decarbonylation reactions to increase the yields of light phenols, light and aromatic

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hydrocarbons. Furthermore, it has been reported that CaO is easily deactivated and Fe-

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based catalysts often occur sintering during the reactions [29, 30]. Therefore, in our

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reaction system, we attributed the higher activity of the Fe(ш)/CaO catalyst to the

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synergistic effect between Fe and CaO support. As shown in the XRD patterns of the

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Fe(ш)/CaO catalyst (shown in Figure 2), when Fe was loaded on the CaO support, the

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Ca2Fe2O5 phase was formed. The Ca2Fe2O5 phase may spread over the CaO support,

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which is helpful to prevent Fe sintering and CaO deactivation in upgrading of biomass

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fast pyrolysis vapors.

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4. Conclusions

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The Fe(ш)/CaO catalyst was prepared and applied for upgrading the biomass fast

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pyrolysis vapors by Py-GC/MS experiments. After catalysis, the heavy phenols were

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transformed to light phenols by removing the methoxyl group and hydrotreating the

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unsaturated C-C bonds on the side chain. The yields of acids, aldehydes and ketones

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were significantly decreased through the deacidification and decarbonylation reaction.

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The yields of furans, light and aromatic hydrocarbons were greatly increased. The

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results indicate that the Fe(ш)/CaO catalyst is more effective in reducing the oxygen

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content of bio-oil, which is good for the improvement of the properties of bio-oil. The

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higher catalytic activities of the Fe(ш)/CaO catalyst could be ascribed to the synergistic

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effect between Fe and CaO support, and the Ca2Fe2O5 phase formed in the catalysts

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might protect CaO support and inhibit Fe sintering in the upgrading reaction.

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Acknowledgments

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The work cited in this paper was funded by National Natural Sciences Foundation of

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China (No.51276104), Natural Science Foundation of Shandong Province of China

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(No.ZR2011BQ013

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Development Project of Shandong Province of China (No.2013GSF11609), and Youth

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Foundation of Shandong Academy of Sciences of China (No.2013QN014).

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Captions of the illustration

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Table 1. Ultimate and proximate analyses of sawdust.

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Table 2. Textural properties of the catalysts.

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Table 3. Main pyrolytic products from fast pyrolysis of sawdust.

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Fig.1. The schematic of Py-GC/MS used in the experiments.

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Fig.2. XRD patterns of the CaO and Fe(ш)/CaO catalysts.

321

Fig.3. CO2-TPD patterns of the catalysts.

322

Fig.4. The total ion chromatograms of sawdust pyrolysis from non-catalytic and

323

catalytic experiments.

324

Fig.5. The catalytic effects on the distribution of the pyrolytic products.

325

Fig.6. The catalytic effects on the yields and compositions of phenolic products.

326

Fig.7. The catalytic effects on the yields and compositions of aldehydes.

327

Fig.8. The catalytic effects on the yields and compositions of ketones.

328

Fig.9. The catalytic effects on the yields and compositions of furans.

329

Fig.10. The catalytic effects on the yields and compositions of light hydrocarbons.

330

Fig.11. The catalytic effects on the yields and compositions of aromatic hydrocarbons.

cr

us

an

M

d

te

Ac ce p

331

ip t

315

16

Page 16 of 31

Table 1 Ultimate and proximate analyses of sawdust Materials Elemental analysis (wt. %)

sawdust

Proximate analysis (wt. %)

C

H

O

N

46.0

5.95

47.7

0.35

Moisture combustibles Ash 8.30

332

2.00

Ac ce p

te

d

M

an

us

cr

333

89.7

ip t

331

17

Page 17 of 31

Table 2. Textural properties of the catalysts

CaO

Surface area (m2/g) 11.2

Pore volume (cm3/g) 0.04

Fe(ш)/CaO

5.94

0.04

sample

334

 

Ac ce p

te

d

M

an

us

cr

335

ip t

333

18

Page 18 of 31

Table 3. Main pyrolytic products from fast pyrolysis of sawdust. No RT(min)

compound

1.6

1,3-Butadiene

2

1.8

Acetaldehyde

3

1.9

2-methyl-1-Buten-3-yne

4

2.2

2-methyl-1-Butene

5

2.5

Acetic acid

6

2.8

Propanoic acid

7

4.6

Toluene

8

5.1

Propanal

9

6.6

Furfural

10

10.0

1,2-Cyclopentanedione

11

12.4

Phenol

12

12.7

13

16.1

14

24.1

15

25.4

16

28.5

17

32.1

4-methyl-2,5-dimethoxy-Benzaldehyde

18

34.8

4-hydroxy-3,5-dimethoxy-Benzaldehyde

19

35.9

2,6-dimethoxy-4-(2-propenyl)-Phenol

20

36.8

1-(4-hydroxy-3,5-dimethoxyphenyl)-Ethanone

21

37.0

4-(-3-hydroxy-1-propenyl)-2-methoxy-Phenol

an

us

cr

ip t

1

M

2,3-dimethyl-Pentanal 2-methoxy-Phenol

2-methoxy-4-vinylphenol 2,6-dimethoxy-Phenol

d

337

 

2-methoxy-4-(1-propenyl)-Phenol

te

336

Ac ce p

335

19

Page 19 of 31

Highlights 

339

The Fe(ш)/CaO catalyst was employed for upgrading of biomass fast pyrolysis vapors. 

340 341 342 343 344

The heavy phenols were transformed to light phenols by the catalysts.  The catalysts eliminated the acids and decreased the aldehydes and ketones.  The furans, light and aromatic hydrocarbons were increased by the catalysts.  The high activity is related to the synergistic effect between Fe and CaO support.   

ip t

338

Ac ce p

te

d

M

an

us

cr

345

20

Page 20 of 31

M

an

us

cr

ip t

Figure(s)

Ac

ce pt

ed

Fig.1. The schematic of Py-GC/MS used in the experiments

Page 21 of 31

Intensity(a.u)

Figure(s)

cr

ip t

Fe(III)/CaO

30

40

50

60

an

20

us

CaO

70

80

M

2 Theta(degree)

Fig.2. XRD patterns of the CaO and Fe(ш)/CaO catalysts. Ca2Fe2O5 phase,  CaO phase,  CaCO3 phase,  Ca(OH)2 phase

Ac

ce pt

ed



Page 22 of 31

Intensity(a.u)

Figure(s)

cr

ip t

Fe(III)/CaO

200

300

400

500

600

700

an

100

us

CaO

800

900

M

o Temperature ( C)

Ac

ce pt

ed

Fig.3. CO2-TPD patterns of the catalysts

Page 23 of 31

Ac

ce pt

ed

M

an

us

cr

ip t

Figure(s)

Fig.4. The total ion chromatograms of sawdust pyrolysis from non-catalytic and catalytic experiments.

Page 24 of 31

Figure(s)

8

1.2x10

phenols acids aldehydes and ketones furans light hydrocarbons aromatic hydrocarbons

8

ip t

1.0x10

7

cr

7

6.0x10

7

4.0x10

us

Peak area

8.0x10

7

an

2.0x10

0.0 none

CaO

Fe(III)/CaO

M

Sawdust and catalysts

Ac

ce pt

ed

Fig.5. The catalytic effects on the distribution of the pyrolytic products

Page 25 of 31

Figure(s)

7

7x10

Phenol 2-methyl-Phenol 3-methyl-Phenol 2-methoxy-Phenol 2-methoxy-4-vinyl-Phenol 2,6-dimethoxy-Phenol 2,6-dimethoxy-4-(2-propenyl)-Phenol 2-methoxy-4-(1-propenyl)-Phenol 4-(3-hydroxy-1-propenyl)-2-methoxy-Phenol

7

ip t

6x10

7

7

cr

4x10

7

3x10

us

Peak area

5x10

7

2x10

7

an

1x10

0

none

CaO

Fe(III)/CaO

M

Sawdust and catalysts

Ac

ce pt

ed

Fig.6. The catalytic effects on the yields and compositions of phenolic products.

Page 26 of 31

Figure(s)

7

6x10

acetaldehyde propanal 2,3-dimethyl-pentanal 4-methyl-2,5-dimethoxybenzaldehyde 4-hydroxy-3,5-dimethoxybenzaldehyde 2-methyl-pentanal 2-methyl-propanal

7

ip t

5x10

cr

7

3x10

7

us

Peak area

7

4x10

2x10

7

0

an

1x10

none

CaO

Fe(III)/CaO

M

Sawdust and catalysts

Ac

ce pt

ed

Fig.7. The catalytic effects on the yields and compositions of aldehydes.

Page 27 of 31

Figure(s)

7

2.5x10

1,2-cyclopentanedione 1-(4-hydroxy-3,5-dimethoxyphenyl)-ethanone 2-pentanone 3-pentanone cyclopentanone 2-methyl-2-cyclopenten-1-one 3-methyl-2-cyclopenten-1-one 2,3-dimethyl-2-cyclopenten-1-one 3-methyl-2-heptanone

7

ip t

7

cr

1.5x10

7

1.0x10

us

Peak area

2.0x10

6

an

5.0x10

0.0 none

CaO

Fe(III)/CaO

M

Sawdust and catalysts

Ac

ce pt

ed

Fig.8. The catalytic effects on the yields and compositions of ketones.

Page 28 of 31

Figure(s)

7

1.6x10

2-methyl-Furan 2,5-dimethyl-Furan Furfural

7

1.4x10

7

ip t

1.2x10

6

cr

8.0x10

6

6.0x10

us

Peak area

7

1.0x10

6

4.0x10

6

an

2.0x10

0.0 none

CaO

Fe(III)/CaO

M

Sawdust and catalysts

Ac

ce pt

ed

Fig.9 The catalytic effects on the yields and compositions of furans.

Page 29 of 31

Figure(s)

7

3.0x10 2.5x10

7

2-methyl-1-butene 1,3-cyclopentadiene 1,2-dimethyl-cyclopropane 1-methyl-1,3-cyclopentadiene 3-methylene-cyclopentene 1,2-dimethyl cyclopropene

7

cr

1.5x10

7

1.0x10

us

Peak area

2.0x10

1,3-butadiene 2-methyl-1-buten-3-yne 1-methoxy-1-propene 1,3-pentadiene 1,4-cyclohexadiene 1,4-hexadiene

ip t

7

6

0.0

none

an

5.0x10

CaO

Fe(III)/CaO

M

Sawdust and catalysts

Ac

ce pt

hydrocarbons.

ed

Fig.10. The catalytic effects on the yields and compositions of light

Page 30 of 31

Figure(s)

7

3.5x10 3.0x10

7

7

cr

2.0x10

7

1.5x10

us

Peak area

2.5x10

ip t

Benzene Toluene 1,3-dimethyl-Benzene Ethylbenzene Styrene Indene

7

7

1.0x10

6

0.0 none

CaO

an

5.0x10

Fe(III)/CaO

M

Sawdust and catalysts

Ac

ce pt

hydrocarbons.

ed

Fig.11. The catalytic effects on the yields and compositions of aromatic

Page 31 of 31