Special Issue "Catalysts for Biomass Conversion"

Guest Editor
Prof. Dr. Michikazu Hara
Materials and Structures Laboratory, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama 226-8503, Japan
Website: http://www.msl.titech.ac.jp/~hara/topEnglish.html
E-Mail: mhara@msl.titech.ac.jp
Interests: catalysis; heterogeneous catalyst; solid acids; cellulosic biomass; hydrolysis; saccharides; glucose; HMF

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Title: Removal of Tar and Sulfur Compounds Derived from Wood using Fe Impregnated Activated Carbon
Author: Toshiaki Hanaoka
Affiliation: Biomass Technology Research Center, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Japan;
E-Mail: t.hanaoka@aist.go.jp
Abstract: Biomass to Liquids (BTL) has been paied attention to recently. This process consists of woody biomass gasification, gas cleaning, and Fishcer-Tropsch (FT) synthesis reaction.  Usually wet gas cleaning method is employed as the second step. In the present work, the removal of tar and suflur derived from wood was studied using Fe modified activated carbon as dry gas cleaning step.  The breakthrough time for H₂S and COS using Fe impregnated activated carbon is longer compared to original activated carbon. And this carbon can not only absorb sulfur compounds but also promote H₂O+COS-->H₂S+CO₂. On a laboratory scale, we will investigate removal of tar using this carbos.  Moreover on a bench scale (wood treatment capacity: 1t/d) we will study the removal of tar and sulfur compounds.

Title: Production of Green Diesel by Hydrotreating Waste Cooking Oils Using Trifunctional Catalysts Containing Co-Mo and Solid Acids
Authors: Yanyong Liu ¹, Rogelio Sotelo-Boyas ², Kazuhisa Murata ¹, Tomoaki Minowa ¹ and Kinya Sakanishi ¹
Affiliations: ¹ Biomass Technology Research Center, National Institute of Advanced Industrial Science and Technology, AIST Tsukuba Center 5, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565, Japan; E-Mail: yy.ryuu@aist.go.jp
² Instituto Politecnico Nacional, Mexico ESIQIE, Mexico D.F. 07738, Mexico
Abstract: Green bio-hydrogenated diesel (BHD) and LPG fuel were produced by hydrotreating waste cooking oils over the catalysts containing Co-Mo and solid acids. A autoclave batch reaction system and a high-pressured flowed fixed-bed reaction system were used for the reaction at 623-673 K under hydrogen pressures of 1-8 MPa. The trifunctional catalysts had the abilities of hydrogenation, deoxidization, and isomerization/cracking, and thus converted waste cooking oils to mixed hydrocarbons in the one-step hydrotreatment. After all unsaturated C=C bonds in oil had been hydrogenated and all C=O bonds in oil had been deoxygenated, long saturated liquid hydrocarbons were formed. Meanwhile, propane was formed after all C=O bonds in triglycerides had been cut off during the hydrotreatment process. The liquid hydrocarbon products can be used as a green diesel for the current diesel engines and the gas hydrocarbon products can be used as a LPG fuel. Because both free fatty acids and triglycerides were deoxygenated at the same time, the waste cooking oils could be converted to BHD and LPG by the hydrotreatment process no matter how much free fatty acids they contained.

Type of Paper: Review
Title: Green and High Quality Biodiesel Fuel Production Process–Catalyst, Raw Materials, Reaction and Separation Systems and Utilization of Biproducts
Author: Yasuaki Maeda
Affiliation: Research Organization for University-Community Collaboration, Osaka Prefecture University, 1-2 Gakuen-cho, Naka-ku, Sakai city, 599-8531, Japan; E-Mail: y-maeda@chem.osakafu-u.ac.jp
Abstract: More than 10 million tons of BDF has been produced in the world from transesterification of vegetable oil with methanol by using acid catalyst (sukfuric acid), alkaline catalyst (NaOH or KOH), solid catalyst and recently enzime and nanocomposite catalyst.Unfortunately, the price of BDF is still more expensive that that of petroleum fuel due to the lack of suitable raw material oil and the need of treatment of bi-products glycerol. Recetly many scientists have studied hydro-reforming of vegetable oil or oil extracts from algae to produce long chain hydrocarbon from the elimination of carboxyl group also by using metal catalysts. To recommend the best selection of BDF production system including raw materials, catalyst and separation. Finally introduce some recent study on the utilization of bi-products glycerol to produce other chemicals by using metal catalyst.

Title: Advances of Fischer-Tropsch Catalysts and Their Potential Application in Biomass to Liquid Conversion
Authors: Jin Hu, Fei Yu and Yongwu Lu
Affiliation: Department of Agricultural and Biological Engineering, Mississippi State University, MS 39762, USA; E-Mail: fyu@abe.msstate.edu
Abstract: Fischer-Tropsch synthesis is a set of catalytic process that can be used to produce fuels and chemicals from synthesis gas (mixture of CO and H₂), which can be derived from natural gas, coal, or biomass. Biomass to Liquid via Fischer-Tropsch (BTLFT) synthesis is gaining increasing interests from academia and industry because of its ability to produce carbon neutral and environmentally friendly clean fuels, such kind of fuels can help to meet the globally increasing energy demand and to meet the stricter environmental regulations in the future. In BTLFT process, biomass, such as woodchips and straw stalk, is firstly converted into biomass-derived syngas (bio-syngas) by gasification. Then cleaning process is applied on bio-syngas to remove impurities to produce clean bio-syngas which meets the Fischer-Tropsch synthesis requirements. Cleaned bio-syngas is then conducted into Fischer-Tropsch catalytic reactor to produce green gasoline, diesel and other clean biofuels. This review will summarize developments of Fischer-Tropsch catalysts in recent years, discuss the key factors on Fischer-Tropsch catalysis, and outlook for the potential application of Fischer-Tropsch catalysts in Biomass to Liquid conversion.

Title: Hydrogen Evolution from Napiergrass by Combination of Cellulase and Pt-dopped TiO₂ under Irradiation
Authors: Masahide Yasuda ¹, Takayuki Tomo ¹, Hikaru Tsumagari ¹, Ryota Yuki ¹, Akiteru Miura ¹, Tsutomu Shiragami ¹, Yasuyuki Ishii ² and Haruhiko Yokoi ¹
Affiliations: ¹ Department of Applied Chemistry, Faculty of Engineering, University of Miyazaki, Gakuen-Kibanadai Nishi, Miyazaki 889-219, Japan; E-Mail: yasuda@cc.miyazaki-u.ac.jp
² Department of Biological Production and Environmental Science, Faculty of Agriculture, University of Miyazaki, Gakuen-Kibanadai Nishi, Miyazaki 889-219, Japan
Abstract: Biomass conversion has been receiving a great amount of interest from viewpoint of a renewable fuels and energy. Especially, much attention has been paid to the lignocellulosic biomass which is not in competition with food sources.  We have focused on a dwarf napiergrass (Pennisetum purpureum Schumach) which is a kind of fodder for livestocks. Here the hydrogen evolution from napiergrass was examined by the sucharification of napiergrass with cellulase followed by the photocatalytic hydrogen evolution by Pt-dopped TiO₂ under UV-irradiation.  Here the reducing sugars which was obtained by the sucharification of napiergrass behaved as sacrificial reagent. At the present time, 3 mol of H₂ and 3 mol of CO₂ were obtained from 1 mol of reducing sugar.

Title: Application of Heterogeneous Catalysis in Small-Scale Biomass Combustion Systems
Author: Ingo Hartmann, René Bindig, Christian Thiel and Mirjam Matthes
Affiliation: DBFZ Deutsches BiomasseForschungsZentrum gemeinnützige GmbH, Torgauer Straße 116, 04347 Leipzig, Germany; E-Mails: ingo.hartmann@dbfz.de (I.H.); Mirjam.Matthes@dbfz.de (M.M.)
Abstract: Combustion of solid biomass fuels for heat generation is an important renewable energy resource. The major part among biomass combustion applications is being played by small scale systems like wood log stoves and small wood pellet burners, which account for 75 % of the overall biomass heat production. Despite of an environmentally friendly use of renewable energies, incomplete combustion in small scale systems can lead to the emission of environmental pollutants as well as health hazardous substances. Harmful emissions occur, in particular, from hand loaded stoves as well as small pellet burners during start-up phases, shutdown phases or partial load operation modes. Besides particles of ash and soot, a wide variety of gaseous substances can also be emitted. Among these are polycyclic aromatic hydrocarbons (PAH) and several organic volatile and semi-volatile compounds (VOC). While flue gas cleaning by precipitation only reduces particulate matter, heterogeneous catalysis is applied for the reduction of various gaseous compounds as well as soot. Some research has been done to examine the application of catalytic converters in small scale biomass combustion systems. In addition to catalyst selection with regard to complete oxidation of different organic substances, further observations on long term stability and resistance under flue gas conditions from biomass combustion furnaces have to be taken into account. Possible catalytic procedures have been identified for investigations, which are reported in literature and are available at the market. Experimental studies with selected catalysts have been carried out on wood log stoves as well as small pellet burners. For analysis with wood log stoves a testing equipment including electrostatic precipitation and a catalyst with heating system is constructed and applied. The measurements have shown that the catalytic flue gas treatment is a promising method to reduce volatile organic compounds. Even a soot oxidation at appropriate temperatures is possible. Emission reduction by use of catalysts in the furnace chamber of pellet burners at higher temperatures is also shown by measurements. Further investigations regarding long term stability of this application have to be made.