W. van Swaaij - Academia.edu (original) (raw)
Papers by W. van Swaaij
Journal of Chemical & Engineering Data, 1994
Pressure-composition isotherms for hydrogen absorption and desorption have been measured for seve... more Pressure-composition isotherms for hydrogen absorption and desorption have been measured for several alloys of the LaNib,Al, family at 298,308,323,333, and 348 K, and the AHo and ASo of the hydride formation reaction were obtained. The equilibrium pressure is strongly related to the aluminum content in the alloy. Other specific properties which have been determined are the density of the metal alloys and the particle size distribution and surface area of the material after about 50 absorptionldesorption cycles with pure hydrogen. Additionally, the solubility and the diffusion coefficient of hydrogen in cyclohexane have been measured, and the solubility of hydrogen in ethanol has been correlated with results available in the literature.
Methanol from Wood II. Current Research and Development Programs
International Journal of Solar Energy, 1984
The current research projects on gasification of biomass for synthesis gas production are reviewe... more The current research projects on gasification of biomass for synthesis gas production are reviewed. Particularly the various pilot plants presently under construction or already in operation at the demonstration scale of 10–50 tons wood/day are discussed in some detail, with emphasis on the demonstration programme of the European CommunitySpecial features, possible disadvantages and areas still requiring additional R & D efforts are indicated for each project. The paper concludes with an outlook on the possible role of catalysis in both primary and secondary gasification and with a discussion on economic feasibility, economics of scale and the need for creative ideas on successfully downscaling of the process.
decomposition of CaSO,, has been investigated in a thermobalance construction provided with a cou... more decomposition of CaSO,, has been investigated in a thermobalance construction provided with a coupled system for the analysis of product gases. By creating suitable reaction conditions in the experimental set-up, it is possible to study this step separately. The apparent solid-solid reaction between CaS and CaSO, takes place when a mixture of these compounds is heated in an inert atmosphere
ChemInform Abstract: Performance of Silica-Supported Copper Oxide Sorbents for SO /NO - Removal from Flue Gas. Part 2. Selective Catalytic Reduction of Nitric Oxide by Ammonia
ChemInform, 1992
ABSTRACT ChemInform is a weekly Abstracting Service, delivering concise information at a glance t... more ABSTRACT ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Wood Pyrolysis and Carbon Dioxide Char Gasification Kinetics in a Fluidized Bed
Fundamentals of Thermochemical Biomass Conversion, 1985
An absorption model has been developed which is able to calculate the simultaneous absorption rat... more An absorption model has been developed which is able to calculate the simultaneous absorption rates (and corresponding enhancement factors) of two gaseous components into a reactive liquid. In the liquid phase multiple complex parallel reversible reactions may take place. This model, for example, can be used for design and development of gas-treating processes for the selective removal of hydrogen sulphide. Due to the implementation of an additional transformation of the spatial coordinate, the required computational time could be reduced substantially without loss of accuracy. The present model can be incorporated into an overall absorption module for column design and simulation. Experimentally determined simultaneous absorption rates of Hz!3 and CO2 in aqueous solutions of alkanolamines and mixtures of alkanolamines can be predicted satisfactorily well for the conditions where both gases have a mutual interaction on the respective rates. The experiments were carried out in a stir...
Effect of Particle Geometry and Microstructure on Fast Pyrolysis of Beech Wood
Energy & Fuels, 2012
ABSTRACT The influence of particle geometry and microstructure in fast pyrolysis of beech wood ha... more ABSTRACT The influence of particle geometry and microstructure in fast pyrolysis of beech wood has been investigated. Milled wood particles (<0.08–2.4 mm) and natural wood cylinders (2–14 mm) with different lengths (10–50 mm) and artificial wood cylinders (Dp = 0.5–14 mm) made of steel walls, filled with small milled wood particles (<0.08–0.140 mm), have been pyrolyzed in a fluidized bed at 500 °C. From the results of the experiments, the influence of particle geometry and microstructure on char, gas, and pyrolysis oil yield and pyrolysis oil composition has been derived. The product yields of large cylinders with diameters of 6–14 mm are primarily determined by the outer diameter and resulting heating rate. The microstructure of these cylinders, being either natural channels or randomly packed small milled wood particles, has turned out to be much less important. For the smaller milled wood particles, the microstructure does have a profound effect on the product yields. The smallest particles (<0.140 mm), which consist only out of cell wall material and have lost their typical wood channel structure, show a clearly higher oil yield and lower char yield. It is postulated that the high pyrolysis oil yield can be explained by larger mass transfer rates of pyrolysis products from these smallest particles, as compared to mass transfer from particles containing channels.
Chemical Engineering Science, 1992
ooo9-2509/92 s5.cIo+o.m Printed in Great Britain. 01992FWgMlOIlRessLM A catalytically active memb... more ooo9-2509/92 s5.cIo+o.m Printed in Great Britain. 01992FWgMlOIlRessLM A catalytically active membrane reactor for fast, exothemic, heterogeneously catalysed reactions
Applications of a Non-Permselective, Catalytically Active Membrane, a Model Study
Chemical Engineering Communications, 1998
ABSTRACT
Continuous Gas Separation With Liquid Impregnated Particles in Gas-Solid Reactors
Chemical Engineering Communications, 1996
ABSTRACT
Gasification of solid waste—Potential and application of co-current moving bed gasifiers
Applied Energy, 1979
A review is given of gasification processes for solid fuels with special emphasis on waste gasifi... more A review is given of gasification processes for solid fuels with special emphasis on waste gasification. Although the co-current moving bed gasifier has not been under consideration for a long time, it offers interesting possibilities for waste gasification. Some operational data are given. Two potential applications are discussed--gasification of agricultural waste (maize cobs) in the rural areas of Tanzania and
Physical absorption of CO2 and propene into toluene/water emulsions
AIChE Journal, 1994
ABSTRACT
Kinetics of COS with primary and secondary amines in aqueous solutions
AIChE Journal, 1992
ABSTRACT
Kinetics of Carbon Dioxide with tertiary Amines in aqueous solution
AIChE Journal, 1990
ABSTRACT
A Non-Permselective Membrane Reactor for the Selective Catalytic Reduction of NOx with Ammonia
Key Engineering Materials, 1992
Survey of Desulfurization Processes for Coal Gas
Desulfurization of Hot Coal Gas, 1998
Gas‐phase polymerization of propylene: Reaction kinetics and molecular weight distribution
Journal of Polymer Science Part A: Polymer Chemistry, 2001
ABSTRACT Gas-phase polymerizations have been executed at different temperatures, pressures, and h... more ABSTRACT Gas-phase polymerizations have been executed at different temperatures, pressures, and hydrogen concentrations using Me2Si[Ind]2ZrCl2 / methylaluminoxane / SiO2(Pennsylvania Quarts) as a catalyst. The reaction rate curves have been described by a kinetic model, which takes into account the initially increasing polymerization rate. The monomer concentration in the polymer has been calculated with the Flory–Huggins equation. The kinetic parameters have been determined by fitting the reaction rate curves with the model. At high temperatures, pressures, and hydrogen concentrations a runaway on particle scale may occur leading to reduced polymer yields. The molecular weight and molecular weight distribution of the polymer samples could be described by a “two-site model.” At constant temperature the chain-transfer probability of sites 1 and 2 depends only on the hydrogen concentration divided by the monomer concentration. © 2001 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 39: 500–513, 2001
Diffusion coefficients of several aqueous alkanolamine solutions
Journal of Chemical & Engineering Data, 1993
... Erwin D. Snijder, Marcel JM te Riele, Geert F. Versteeg; and WP M. van Swaaij ... Furthermore... more ... Erwin D. Snijder, Marcel JM te Riele, Geert F. Versteeg; and WP M. van Swaaij ... Furthermore, a modified Stokes-Einstein relation is presented for the prediction of the diffusion coefficients in the alkanolamines in relation to the viscosity of the solvent and the diffusion coefficient at ...
Comparison of gas- and liquid-phase polymerization of propylene with heterogeneous metallocene catalyst
Journal of Applied Polymer Science, 2001
ABSTRACT Sorption measurements are executed to study the sorption behavior of propylene in a semi... more ABSTRACT Sorption measurements are executed to study the sorption behavior of propylene in a semicrystalline polymer. Decreasing values for the Flory–Huggins interaction parameter with increasing temperature are obtained. Large deviations are found, especially at higher temperatures, compared to data from the literature. Propylene is polymerized in liquid and gaseous propylenes with Me2Si[Ind]2ZrCl2/MAO/SiO2 as the metallocene catalyst. Lower relative reaction rates are found in the gas phase compared to the experiments in the liquid phase. The activation energies from the experiments in both phases are on the same order of magnitude. However, the literature versus experimental sorption data has a large effect on the determined kinetic parameters. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 1193–1206, 2001
Industrial & Engineering Chemistry Research, 1997
A screen heater with a gas sweep was developed and applied to study the pyrolysis kinetics of low... more A screen heater with a gas sweep was developed and applied to study the pyrolysis kinetics of low density polyethene (LDPE) and polypropene (PP) at temperatures ranging from 450 to 530°C
Journal of Chemical & Engineering Data, 1994
Pressure-composition isotherms for hydrogen absorption and desorption have been measured for seve... more Pressure-composition isotherms for hydrogen absorption and desorption have been measured for several alloys of the LaNib,Al, family at 298,308,323,333, and 348 K, and the AHo and ASo of the hydride formation reaction were obtained. The equilibrium pressure is strongly related to the aluminum content in the alloy. Other specific properties which have been determined are the density of the metal alloys and the particle size distribution and surface area of the material after about 50 absorptionldesorption cycles with pure hydrogen. Additionally, the solubility and the diffusion coefficient of hydrogen in cyclohexane have been measured, and the solubility of hydrogen in ethanol has been correlated with results available in the literature.
Methanol from Wood II. Current Research and Development Programs
International Journal of Solar Energy, 1984
The current research projects on gasification of biomass for synthesis gas production are reviewe... more The current research projects on gasification of biomass for synthesis gas production are reviewed. Particularly the various pilot plants presently under construction or already in operation at the demonstration scale of 10–50 tons wood/day are discussed in some detail, with emphasis on the demonstration programme of the European CommunitySpecial features, possible disadvantages and areas still requiring additional R & D efforts are indicated for each project. The paper concludes with an outlook on the possible role of catalysis in both primary and secondary gasification and with a discussion on economic feasibility, economics of scale and the need for creative ideas on successfully downscaling of the process.
decomposition of CaSO,, has been investigated in a thermobalance construction provided with a cou... more decomposition of CaSO,, has been investigated in a thermobalance construction provided with a coupled system for the analysis of product gases. By creating suitable reaction conditions in the experimental set-up, it is possible to study this step separately. The apparent solid-solid reaction between CaS and CaSO, takes place when a mixture of these compounds is heated in an inert atmosphere
ChemInform Abstract: Performance of Silica-Supported Copper Oxide Sorbents for SO /NO - Removal from Flue Gas. Part 2. Selective Catalytic Reduction of Nitric Oxide by Ammonia
ChemInform, 1992
ABSTRACT ChemInform is a weekly Abstracting Service, delivering concise information at a glance t... more ABSTRACT ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Wood Pyrolysis and Carbon Dioxide Char Gasification Kinetics in a Fluidized Bed
Fundamentals of Thermochemical Biomass Conversion, 1985
An absorption model has been developed which is able to calculate the simultaneous absorption rat... more An absorption model has been developed which is able to calculate the simultaneous absorption rates (and corresponding enhancement factors) of two gaseous components into a reactive liquid. In the liquid phase multiple complex parallel reversible reactions may take place. This model, for example, can be used for design and development of gas-treating processes for the selective removal of hydrogen sulphide. Due to the implementation of an additional transformation of the spatial coordinate, the required computational time could be reduced substantially without loss of accuracy. The present model can be incorporated into an overall absorption module for column design and simulation. Experimentally determined simultaneous absorption rates of Hz!3 and CO2 in aqueous solutions of alkanolamines and mixtures of alkanolamines can be predicted satisfactorily well for the conditions where both gases have a mutual interaction on the respective rates. The experiments were carried out in a stir...
Effect of Particle Geometry and Microstructure on Fast Pyrolysis of Beech Wood
Energy & Fuels, 2012
ABSTRACT The influence of particle geometry and microstructure in fast pyrolysis of beech wood ha... more ABSTRACT The influence of particle geometry and microstructure in fast pyrolysis of beech wood has been investigated. Milled wood particles (<0.08–2.4 mm) and natural wood cylinders (2–14 mm) with different lengths (10–50 mm) and artificial wood cylinders (Dp = 0.5–14 mm) made of steel walls, filled with small milled wood particles (<0.08–0.140 mm), have been pyrolyzed in a fluidized bed at 500 °C. From the results of the experiments, the influence of particle geometry and microstructure on char, gas, and pyrolysis oil yield and pyrolysis oil composition has been derived. The product yields of large cylinders with diameters of 6–14 mm are primarily determined by the outer diameter and resulting heating rate. The microstructure of these cylinders, being either natural channels or randomly packed small milled wood particles, has turned out to be much less important. For the smaller milled wood particles, the microstructure does have a profound effect on the product yields. The smallest particles (<0.140 mm), which consist only out of cell wall material and have lost their typical wood channel structure, show a clearly higher oil yield and lower char yield. It is postulated that the high pyrolysis oil yield can be explained by larger mass transfer rates of pyrolysis products from these smallest particles, as compared to mass transfer from particles containing channels.
Chemical Engineering Science, 1992
ooo9-2509/92 s5.cIo+o.m Printed in Great Britain. 01992FWgMlOIlRessLM A catalytically active memb... more ooo9-2509/92 s5.cIo+o.m Printed in Great Britain. 01992FWgMlOIlRessLM A catalytically active membrane reactor for fast, exothemic, heterogeneously catalysed reactions
Applications of a Non-Permselective, Catalytically Active Membrane, a Model Study
Chemical Engineering Communications, 1998
ABSTRACT
Continuous Gas Separation With Liquid Impregnated Particles in Gas-Solid Reactors
Chemical Engineering Communications, 1996
ABSTRACT
Gasification of solid waste—Potential and application of co-current moving bed gasifiers
Applied Energy, 1979
A review is given of gasification processes for solid fuels with special emphasis on waste gasifi... more A review is given of gasification processes for solid fuels with special emphasis on waste gasification. Although the co-current moving bed gasifier has not been under consideration for a long time, it offers interesting possibilities for waste gasification. Some operational data are given. Two potential applications are discussed--gasification of agricultural waste (maize cobs) in the rural areas of Tanzania and
Physical absorption of CO2 and propene into toluene/water emulsions
AIChE Journal, 1994
ABSTRACT
Kinetics of COS with primary and secondary amines in aqueous solutions
AIChE Journal, 1992
ABSTRACT
Kinetics of Carbon Dioxide with tertiary Amines in aqueous solution
AIChE Journal, 1990
ABSTRACT
A Non-Permselective Membrane Reactor for the Selective Catalytic Reduction of NOx with Ammonia
Key Engineering Materials, 1992
Survey of Desulfurization Processes for Coal Gas
Desulfurization of Hot Coal Gas, 1998
Gas‐phase polymerization of propylene: Reaction kinetics and molecular weight distribution
Journal of Polymer Science Part A: Polymer Chemistry, 2001
ABSTRACT Gas-phase polymerizations have been executed at different temperatures, pressures, and h... more ABSTRACT Gas-phase polymerizations have been executed at different temperatures, pressures, and hydrogen concentrations using Me2Si[Ind]2ZrCl2 / methylaluminoxane / SiO2(Pennsylvania Quarts) as a catalyst. The reaction rate curves have been described by a kinetic model, which takes into account the initially increasing polymerization rate. The monomer concentration in the polymer has been calculated with the Flory–Huggins equation. The kinetic parameters have been determined by fitting the reaction rate curves with the model. At high temperatures, pressures, and hydrogen concentrations a runaway on particle scale may occur leading to reduced polymer yields. The molecular weight and molecular weight distribution of the polymer samples could be described by a “two-site model.” At constant temperature the chain-transfer probability of sites 1 and 2 depends only on the hydrogen concentration divided by the monomer concentration. © 2001 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 39: 500–513, 2001
Diffusion coefficients of several aqueous alkanolamine solutions
Journal of Chemical & Engineering Data, 1993
... Erwin D. Snijder, Marcel JM te Riele, Geert F. Versteeg; and WP M. van Swaaij ... Furthermore... more ... Erwin D. Snijder, Marcel JM te Riele, Geert F. Versteeg; and WP M. van Swaaij ... Furthermore, a modified Stokes-Einstein relation is presented for the prediction of the diffusion coefficients in the alkanolamines in relation to the viscosity of the solvent and the diffusion coefficient at ...
Comparison of gas- and liquid-phase polymerization of propylene with heterogeneous metallocene catalyst
Journal of Applied Polymer Science, 2001
ABSTRACT Sorption measurements are executed to study the sorption behavior of propylene in a semi... more ABSTRACT Sorption measurements are executed to study the sorption behavior of propylene in a semicrystalline polymer. Decreasing values for the Flory–Huggins interaction parameter with increasing temperature are obtained. Large deviations are found, especially at higher temperatures, compared to data from the literature. Propylene is polymerized in liquid and gaseous propylenes with Me2Si[Ind]2ZrCl2/MAO/SiO2 as the metallocene catalyst. Lower relative reaction rates are found in the gas phase compared to the experiments in the liquid phase. The activation energies from the experiments in both phases are on the same order of magnitude. However, the literature versus experimental sorption data has a large effect on the determined kinetic parameters. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 1193–1206, 2001
Industrial & Engineering Chemistry Research, 1997
A screen heater with a gas sweep was developed and applied to study the pyrolysis kinetics of low... more A screen heater with a gas sweep was developed and applied to study the pyrolysis kinetics of low density polyethene (LDPE) and polypropene (PP) at temperatures ranging from 450 to 530°C