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LJP van den Broeke

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19 records found

Homogeneous reactions in supercritical carbon dioxide using a catalyst immobilized by a microporous silica membrane

Journal article - LJP van den Broeke, Earl Goetheer, Arjan W. Verkerk, Elwin de Wolf, Berth Jan Deelman, Gerard van Koten, J. T.F. Keurentjes

Membrane separation technology is successfully applied for the immobilization of a homogeneous catalyst (a (1H, 1H, 2H, 2H-perfluoroalkyl)-dimethylsilyl-substituted derivative of Wilkinson's catalyst) in a continuous process that uses supercritical carbon dioxide as solvent. The ...

Permeation of carbon dioxide through a microporous silica membrane at subcritical and supercritical conditions

Journal article - A. W. Verkerk, A. W. Verkerk, Earl Goetheer, LJP van den Broeke, J. T.F. Keurentjes

The one-component transient permeation of carbon dioxide through an alumina-supported silica membrane is studied for pressures up to 2.0 × 107 Pa, at temperatures of 296, 313, and 358 K. The permeation is obtained for gaseous, liquid, and supercritical carbon dioxide. For all con ...

Functionalized poly(propylene imine) dendrimers as novel phase transfer catalysts in supercritical carbon dioxide

Journal article - Earl Goetheer, M. W.P.L. Baars, LJP van den Broeke, E. W. Meijer, J. T.F. Keurentjes

Perfluoro-functionalized poly(propylene imine) dendrimers have been used as reactive extractants for anionic species and as phase transfer catalysts for two types of reactions. Different generations of dendrimers have been used for applications in carbon dioxide. First, the reactive extraction of the inorganic ions permanganate and dichromate, from an aqueous phase to a supercritical carbon dioxide phase, has been studied using the functionalized dendrimers. The yield for these extractions is rather low, indicating that the perfluoro-functionalized poly(propylene imine) dendrimers are not suited for oxidation reactions with these ions in carbon dioxide. Second, the poly(propylene imine) dendrimers have been used as a phase transfer catalyst for the halogen exchange reaction of benzyl chloride into benzyl bromide and for the esterification of oxalic acid with pentafluorobenzylbromide. In contrast with the low extraction yield for the inorganic permanganate and dichromate ions, a high reaction rate was obtained for the halogen exchange reaction with the functionalized dendrimers as phase transfer catalysts. It is found that the rate of reaction for both cases depends on the generation number of the dendrimer. For the higher-generation dendrimers, it is more difficult for the substrate to migrate from the bulk carbon dioxide phase to the interior of the dendrimer. This indicates that the mass transfer of the reagents from the organic phase into the interior of the dendrimer determines the reaction rate for the fourth and higher generation dendrimers. A model is proposed to describe the extraction and the phase transfer catalysis based on the fact that the modified dendrimers combine micellar properties with those of standard phase transfer catalysts. From the different experiments it can be concluded that the perfluoro-functionalized poly(propylene imine) dendrimers have great potential as multisite phase transfer catalysts.@en

Use of on-line uv/vis-spectrometry in the measurements of dissolved ozone and aoc concentrations in drinking water treatment

Journal article - LJP van den Broeke, P.S. Ross, A.W.C. van der Helm, ET Baars, L.C. Rietveld

Drinking water treatment: online estimation of biological stability using uv-spectrography

Conference paper - P.S. Ross, LJP van den Broeke, L.C. Rietveld

On-line monitoring of drinking water treatment efficacy using uv/vis-spectrometry

Conference paper - LJP van den Broeke, A.W.C. van der Helm, L.C. Rietveld, P.S. Ross

Effect of raw water quality on performance of ozone and biofiltration based on modelling and on-line monitoring

Conference paper - P.S. Ross, A.W.C. van der Helm, LJP van den Broeke, L.T.J. van der Aa, L.C. Rietveld

Drinking water treatment: biological stability assessed using uv-spectrography

Conference paper - P.S. Ross, A.W.C. van der Helm, LJP van den Broeke, M Dignum, L.C. Rietveld, J.C. van Dijk

Characterization of nom and uv spectrography in drinking water treatment processes to assess biological stability

Conference paper - P.S. Ross, A.W.C. van der Helm, LJP van den Broeke, L.T.J. van der Aa, L.C. Rietveld

Binary adsorption equilibrium of organic and water on activated carbon.

Journal article - MJG Linders, LJP van den Broeke, JJGM van Bokhoven, F. Kapteijn, J.A. Moulijn

Modelling sorption and diffusion in activated carbon: a novel low pressure pulse-response technique.

Journal article - MJG Linders, LJP van den Broeke, TA Nijhuis, F. Kapteijn, J.A. Moulijn

Bioseparations in aqueous micellar systems based on excluded-volume interactions

Journal article - D. van Roosmalen, M Dohmen-Speelmans, CHJT Dietz, LJP van den Broeke, L.A.M. van der Wielen, JTF Keurentjes

Characteristics of protein partitioning in an aqueous micellar-gel system

Journal article - LJP van den Broeke, D. van Roosmalen, M Dohmen-Speelmans, CHJT Dietz, L.A.M. van der Wielen, JTF Keurentjes

Online monitoring of the solvent and absorbed acid gas concentration in a CO2 capture process using monoethanolamine

Journal article - A.C. van Eckeveld, LV van der Ham, LFG Geers, LJP van den Broeke, B.J. Boersma, B.J. Boersma, ELV Goetheer

On-line estimation of biological stability in drinking water treatment

Conference paper - P.S. Ross, LJP van den Broeke, L.C. Rietveld

UV-spectrography for on-line estimation of biological parameters

Conference paper - P.S. Ross, LJP van den Broeke, L.C. Rietveld

Protein separation using partitioning over nonionic micellar aqueous two-phase systems

Conference paper - D. van Roosmalen, CHJT Dietz, M Dohmen-Speelmans, DA Horneman, M. Ottens, L.A.M. van der Wielen, LJP van den Broeke, JTF Keurentjes

The versatility of online uv/vis spectrometry - an overview

Book chapter - LJP van den Broeke, P.S. Ross, F Edthofer, A.W.C. van der Helm, a Weingartner, L.C. Rietveld

Use of on-line uv/vis-spectrometry in the measurement of dissolved ozone and aoc concentration in drinking water treatment

Conference paper - LJP van den Broeke, P.S. Ross, A.W.C. van der Helm, E.T. Baars, L.C. Rietveld

Contributed

1 records found

The use of green H2 and sustainable carburization to Fe3C for the direct reduction of iron ore pellets

Master thesis - H.J. van Leeuwen, T.J.H. Vlugt, O. Moultos, P. Dey, LJP van den Broeke

Steel manufacturing is a carbon intensive process, that is responsible for approximately 7% of the total global CO2 emissions. Therefore, TATA Steel IJmuiden aims to lower its carbon emissions. One way to bring down emissions, is to replace the existing blast furnace (BF) CO reduction process with the H2-based direct reduction of iron ore (DRI). The two most widely applied H2-DRI processes around the world are the low pressure MIDREX, abbreviated as MLP, and medium pressure HYL-Energiron, abbreviated as EMP. Since TATA Steel IJmuiden wants to study the switch from BF to H2-DRI steelmaking, it is relevant to gain insight into which gas phase reactions are dominant for both processes, into the direct reduction process itself and into the behaviour of the carburization reactions that improve the steel quality. In the gas phase reactions, it was seen that for the MLP process in situ reforming of natural gas can be a viable option before switching to a 100% H2 process. This may prove to be worthwhile in the early stages of H2-DRI steel production, when green H2 is still scarce and expensive. For EMP, internal reforming seems less of a possibility due to the high reaction rate for the reverse water gas-shift. When comparing both MLP and EMP, reaction rates are generally higher for EMP than for MLP and hence smaller reactor volumes are required for the EMP process to acquire the same amount of output. Direct reduction with H2 has a higher reaction rate than reduction with CO, while for the carburization reactions methane cracking was found to be the dominant reaction. Techno-economic scenarios for 100% H2-based DRI in which green H2 is imported are only feasible when H2-prices fall below €1.80/kg. Meanwhile, a scenario with an on-site electrolyzer powered by grey grid electricity only proves to be worthwhile for electricity prices lower than €20/MWh. The most promising techno-economic scenario, which includes an on-site electrolyzer and the construction of a wind farm just off the coast from the TATA Steel IJmuiden site, assumes an electricity price of €40/MWh.