Search

In this research, rubber wood sawdust (RWS) and Meranti wood sawdust (MWS) were pyrolyzed in a fixed bed drop-type pyrolyzer under an inert condition. The first part of the study is to determine the influence of pyrolysis temperature (450, 500, 550, 600, 650 °C) on the yield of pyrolysis products. Pyrolysis of these different residues generate an almost identical maximum amount of bio-oil close to 33 wt.%, but at different maximum temperature (550 °C for pyrolysis of RWS and 600 °C for pyrolysis of MWS). To evaluate the effect of biomass type on the composition and characterization of pyrolysis products, the second part involves the analyses of pyrolysis products from the maximum pyrolysis temperature. Acetic acid, tetrahydrofuran, and benzene were the main bio-oil components. The bio-oil contained high percentage of oxygen and hydrogen, indicating high water content in the bio-oil. High amount of water in bio-oil significantly reduced its calorific value. Under extensive heating, particle size of the bio-char from SEM images decreased due to breakage and shrinkage mechanisms. The major components of non-condensable gases were CO and CO 2 . [ABSTRACT FROM AUTHOR]

Non-catalytic and catalytic fast pyrolysis of paddy husk was performed with a medium pore framework zeolite (MCM-22) and its delaminated counterpart with a higher external surface area (ITQ-2) using a lab scale fixed-bed reactor. This work investigates the influence of the catalyst physical structure on the yields of gas, liquid and solid products and gas composition. The maximum pyrolysis oil yield of 34.8% (water 15.1 %, organics 19.7%) was obtained at 450 °C. At this temperature, catalytic pyrolysis was carried out using MCM-22 and ITQ-2. A mixture of 10 grams of rice husk and a prescribed amount of catalyst (0.5, 1 or 5 g) was used for catalytic pyrolysis. By using catalysts, the pyrolysis oil yield decreases. This decrement in pyrolysis oil yield is attributed to catalytic cracking of pyrolysis oil vapor on the catalyst. Decarbonylation and decarboxylation were identified as the major reactions in this cracking. Comparison of results for MCM-22 with ITQ-2, ITQ-2 culminated in slightly higher pyrolysis oil yield than those of MCM-22. This may be attributed to ITQ-2’s thinner delaminated structure compared to MCM-22. Thinner structure makes the reactants (molecules of pyrolysis oil) more accessible to the catalytic sites and let the products (upgraded molecules generated from pyrolysis oil) leave from the catalytic sites to the bulk faster. ITQ-2 possessed high acid active sites and large external surface area which were responsible for high deoxygenation of oxygenated species and enhanced the production of aromatic hydrocarbons. [ABSTRACT FROM AUTHOR]

Torrefaction of oil palm kernel shell (PKS), one of the biomass residues from the palm oil industry, was carried out in a fixed-bed tubular reactor in the presence of oxygen and carbon dioxide at concentrations ranging from 0 to 15 vol.% (nitrogen balance). The effects of oxygen and carbon dioxide concentrations (0, 3, 9, 12, and 15 vol.%), temperature (493, 523, and 573 K) and biomass size (0.375 mm and unground) on the solid phase conversion, the energy yield and properties of torrefied biomass were investigated. The solid phase conversion increased with increasing temperature and oxygen or carbon dioxide concentration, but was not significantly affected by biomass size. The energy yield decreased with increasing oxygen or carbon dioxide concentration, but was still more than 70%. The extent of torrefaction was in the order of oxygen > carbon dioxide > nitrogen. The ‘oxidative torrefaction’ rate was extracted from the overall reaction rate. The increase in the oxidative torrefaction rate caused by oxygen was higher than that caused by carbon dioxide. Scanning electron microscope observations of the morphology of the PKS showed distinctive differences for torrefaction in nitrogen, oxygen, and carbon dioxide. [ABSTRACT FROM AUTHOR]

This study evaluated the potential of bioflocculant production from Aspergillus niger using palm oil mill effluent (POME) as carbon source. The bioflocculant named PM-5 produced by A. niger showed a good flocculating capability and flocculating rate of 76.8% to kaolin suspension could be achieved at 60 h of culture time. Glutamic acid was the most favorable nitrogen source for A. niger in bioflocculant production at pH 6 and temperature 35 °C. The chemical composition of purified PM-5 was mainly carbohydrate and protein with 66.8% and 31.4%, respectively. Results showed the novel bioflocculant (PM-5) had high potential to treat river water from colloids and 63% of turbidity removal with the present of Ca 2+ ion. [ABSTRACT FROM AUTHOR]

[Display omitted] • Co and Pd-Co catalyzed simultaneously the CArO−CH3, CAr−OH and successive C−C hydrogenolysis. • Fe and Pd-Fe catalyzed principally the CAr−OCH3 hydrogenolysis. • Addition of Pd significantly enhanced the stability of Fe and Co catalyst. • The successive pyrolysis and catalytic upgrading of lignin produced an upgraded bio-oil. • Pd-Fe/Al-MCM-41 was a potential catalyst for upgrading of lignin-derived bio-oil. Fast pyrolysis of lignocellulosic biomass is an attractive process to produce bio-oil as an alternative liquid fuel source. Upgrading of bio-oil via hydrodeoxygenation (HDO) is an important route to accomplish this renewable energy production process. Al-MCM-41 supported Pd, Co and Fe catalysts were evaluated for HDO of guaiacol and lignin-derived bio-oil at atmospheric pressure in a fixed-bed reactor. Bimetallic Pd-Co and Pd-Fe catalysts showed higher HDO yield and stability than the monometallic Co and Fe catalysts. The addition of Pd significantly enhanced the stability of Co and Fe catalysts since it helped reduce the coke formation. The lignin-derived bio-oil mainly contained phenolic compounds which had one to three oxygen atoms. The catalytic upgrading could not only eliminate significantly the oxygen of these phenolic compounds but also reduce the amount of tar and heavy components. Pd-Fe catalyst was recognized as a suitable catalyst for upgrading of lignin-derived bio-oil since it produced more deoxygenated products and less gas-phase yield than Pd-Co catalyst. [ABSTRACT FROM AUTHOR]

This paper investigates the effects of four reaction parameters that include type of catalyst, catalyst loading, reaction temperature and nitrogen gas flowrate on the liquid (bio-oil) yield from the catalytic pyrolysis of Empty Fruit Bunch (EFB). The experimental design is based on Taguchi's L9 Orthogonal Array in which the reaction parameters are varied at three levels. The maximum liquid yield is predicted based on systematic experimental runs, and is found to be at 5 wt-% of H-Y catalyst, 500 °C and at nitrogen flowrate of 100 ml min −1 . The predicted maximum liquid yield is validated with an experimental run at the corresponding predicted conditions. The bio-oil produced at the optimum reaction condition is characterized and compared with known bio-oil standards in the literature. [ABSTRACT FROM AUTHOR]

Highlights: [•] Catalytic fast pyrolysis of paddy husk was studied in a lab scale drop type fixed-bed pyrolyzer. [•] Bio-oil generated from catalytic pyrolysis had low organic content and high water content. [•] Secondary degradation reactions by the catalyst promoted the formation of furans. [•] Excess amount of catalyst produced more water and less quality bio-oil. [Copyright &y& Elsevier]

Torrefaction refers to a thermochemical treatment that reduces the moisture content of biomass and increases its energy density by removing water and lower energy volatiles. Torrefaction process requires mild treatment temperature between 200 to 300 ˚C in the absence of oxygen (inert atmosphere). Through torrefaction, biomass transformed into a char-like solid with higher value than the raw biomass. Industries found it applicable for the torrefied biomass to be co-fired with coal in power plants because of the close similarity in properties. The torrefied biomass can also be used as feedstock for entrained-flow gasifier, or for residential heating. During torrefaction, a continuous supply of nitrogen to create the needed inert state incurs certain cash flow to the torrefaction plant; meanwhile the nitrogen price is depending on the volatile prices of natural gas that is currently suffered from depletion. The alternative of this problem is to utilize flue gas as a replacement of the nitrogen in parallel with the fact that nitrogen is a major composition of flue gas. A fundamental study is needed to support the idea, for that reason this paper studied how the behaviour of torrefaction diverged when the process was carried out in the presence of oxygen and carbon dioxide. The chosen biomass is oil palm kernel shell (PKS) due to its abundance in Malaysia. The torrefactionis carried out 250 ˚C for30 min. In comparison to the solid yield of torrefied PKS in inert torrefaction, the solid yield in oxygen and carbon dioxidetorrefactionis practically unaffected by the non-inert gases. Liquid yield is almost similar in each torrefactioncondition;however the gas yield in carbon dioxide torrefaction is produced intensely compared to the gas yield in oxygen torrefaction. [ABSTRACT FROM AUTHOR]

Application of microtube reactor for the continuous synthesis of biodiesel has been widely studied due to excellent performance in liquid-liquid phase reaction. In order to commercialize biodiesel production, integration of microtube reactor is highly recommended. Therefore, in this study, synthesis of biodiesel was carried out in capillary millichannel reactor with inner diameter of 1.59 mm using methanol and potassium hydroxide (KOH) as base catalyst with palm oil as a feedstock. The influences of reaction temperature, methanol to oil molar ratio, and KOH concentration on the production of fatty acid methyl ester (FAME) were examined. The highest FAME yield was achieved at 60 ˚C with 23:1 methanol to oil molar ratio and 5 wt% of KOH concentration. [ABSTRACT FROM AUTHOR]

In general, lignocellulosic biomass contains three major components, namely lignin, hemicellulose and cellulose which are the polymers of C5 and C6 sugars. Thus, there is potential to utilize of this biomass for bioethanol production. The hydrolysis of cellulose into glucose was difficult due to the more fibrous nature and thus inhibit enzyme penetration into the cellulose. In order to solve this problem, hydrothermal pretreatment can be used for breaking the bonds within the lignin structure and increase the accessibility of enzyme into the cellulose. In this study, the effect of chemical addition, sodium hydroxide (NaOH) and calcium oxide (CaO) in hydrothermal pretreatment at 180 °C and 30 minutes reaction time of palm oil empty fruit bunches (EFB) on the enzymatic hydrolysis efficiencies was investigated. The enzymatic hydrolysis of hydrothermally pretreated EFB give the highest concentration of glucose at 0.67 g/L while the hydrothermally pretreated of EFB in the presence of NaOH gives the lowest glucose concentration 0.45 g/L. [ABSTRACT FROM AUTHOR]