Bernard P. A. Grandjean

Bio: Bernard P. A. Grandjean is an academic researcher from Laval University. The author has contributed to research in topics: Pressure drop & Mass transfer. The author has an hindex of 34, co-authored 92 publications receiving 3830 citations. Previous affiliations of Bernard P. A. Grandjean include École Polytechnique de Montréal.

Catalytic palladium‐based membrane reactors: A review

Abstract: This paper is an extensive review of the literature dealing with the class of catalytic membrane reactors which involves hydrogen permeable membranes made of palladium and palladium alloys. The fundamental factors which affect hydrogen permeability are first discussed. A classification of the many reactions which have been conducted in such reactors at both laboratory and commercial scales is then presented. The various techniques for the preparation of palladium- based membranes are described and the literature on modeling and design of these reactors is also reviewed.

Methane steam reforming in asymmetric Pd- and Pd-Ag/porous SS membrane reactors

Abstract: This work is devoted to applying electrolessly deposited Pd- and Pd-Ag/porous stainless steel composite membranes in methane steam reforming The methane conversion is significantly enhanced by the partial removal of hydrogen from the reaction location as a result of diffusion through the Pd-based membranes For example, at a total pressure of 136 kPa, a temperature of 500°C, a molar steam-to-methane ratio of 3, and in the presence of a commercial Ni/Al2O3 catalyst together with continuous pumping on the permeation side, a methane conversion twice as high as that in a non-membrane reactor was reached by using a Pd/SS membrane These effects were examined under a variety of experimental conditions A computer model of the membrane reactor was also developed to predict the effects of membrane separation on methane conversion

Industrial use of immobilized enzymes

Abstract: Although many methods for enzyme immobilization have been described in patents and publications, relatively few processes employing immobilized enzymes have been successfully commercialized. The cost of most industrial enzymes is often only a minor component in overall process economics, and in these instances, the additional costs associated with enzyme immobilization are often not justified. More commonly the benefit realized from enzyme immobilization relates to the process advantages that an immobilized catalyst offers, for example, enabling continuous production, improved stability and the absence of the biocatalyst in the product stream. The development and attributes of several established and emerging industrial applications for immobilized enzymes, including high-fructose corn syrup production, pectin hydrolysis, debittering of fruit juices, interesterification of food fats and oils, biodiesel production, and carbon dioxide capture are reviewed herein, highlighting factors that define the advantages of enzyme immobilization.

Membranes for hydrogen separation.

Abstract: 3.2. Preparation 4090 3.3. Intermediate Layers 4090 3.4. Support 4090 3.5. Modification 4091 3.5.1. Silica Membrane Modification 4091 3.5.2. Membrane Structure Modification 4092 3.6. Operational Stability 4092 4. Zeolite Membranes 4092 4.1. Membrane Growth Methods 4093 4.2. Permeation and Gas Transport 4093 4.3. Defect Site Diffusion/Nonzeolitic Pores 4094 4.4. Thin Films 4094 4.5. Zeolite Membrane Modification 4094 4.6. CO2 Sequestration in H2 Separations 4095 4.7. Manufacturing 4095 5. Carbon-Based Membranes 4096 5.1. Carbon Membrane Preparations 4097 5.2. Carbon Membrane Post-treatment 4097 5.3. Carbon Membrane Module Construction 4097 5.4. Selective Surface Flow Membranes 4097 5.5. Disadvantages of Carbon Membranes 4098 5.6. Molecular Sieving Carbon Membranes 4098 5.7. Carbon Nanotubes 4099 6. Polymer Membranes for H2 Separations 4100 6.1. Dense Polymeric Membranes 4100 6.2. Hydrogen Selective Polymeric Membranes 4101 6.3. H2 versus CO2 Selective Polymeric Membranes 4103

New catalytic routes for syngas and hydrogen production

Abstract: This review summarizes different catalytic options for the production of syngas and hydrogen starting from simple hydrogen-containing molecules. Particular attention is given to new direct catalytic alternatives in natural gas conversion. Improvements in syngas technology are discussed, including partial oxidation, autothermal reforming, combined reforming and carbon dioxide reforming, and the energy efficiencies of direct and indirect methane conversion are compared. Processes, issues and practical difficulties are discussed with academic and applied efforts presented in parallel. It is emphasized that most of the ongoing research related to the direct processes is at the exploratory stage while technology utilizing indirect approach has advanced to semi-works and initial commercialization plants. The new emerging processes based on partial oxidation features are unique for syngas generation. Further enhancement of such processes plus improvements in other second generation technologies and advances in direct processes are anticipated to provide additional, new attractive paths to the chemical conversion of natural gas. Similarly, on board generation of hydrogen-rich gaseous fuels either for spark ignition engines or for coupled-fuel-cells electric engines is discussed within the scope of both partial oxidation and catalytic decomposition of methanol. A concept based in the thermochemical water splitting, which provides a renewable portable fuel from water in the form of H2, is also presented. Above all, as the chemistry involved in most of these catalytic alternatives takes place under extreme conditions, highly stable catalysts and engineering concepts are being developed.

Innovations in palladium membrane research

Abstract: This review highlights various aspects of current palladium membrane research and serves as a comprehensive bibliography covering palladium membrane preparation methods and applications. There are many promising uses for palladium membranes, although widespread use of the available technologies is constrained primarily by the high cost of palladium, lack of durability due to hydrogen embrittlement, and susceptibility to fouling. Various researchers in the field are tackling these problems and fabricating thinner palladium alloy composite membranes that better withstand contaminantion and thermal cycling. What has been accomplished to address these issues and the directions presently being explored are discussed.