English
 
User Manual Privacy Policy Disclaimer Contact us
  Advanced SearchBrowse

Item

ITEM ACTIONSEXPORT
 
 
DownloadE-Mail
  Upgrading of lignocellulose-derived sugars to value-added chemicals via heterogeneously catalyzed continuous-flow processes

Bäumel, M. (2019). Upgrading of lignocellulose-derived sugars to value-added chemicals via heterogeneously catalyzed continuous-flow processes. PhD Thesis, Technische Universität Berlin, Berlin. doi:10.14279/depositonce-9097.

Item is

Basic

show hide
Item Permalink: http://hdl.handle.net/21.11116/0000-0005-D633-0 Version Permalink: http://hdl.handle.net/21.11116/0000-0005-D634-F
Genre: Thesis

Files

show Files
hide Files
:
Thesis.pdf (Any fulltext), 14MB
Name:
Thesis.pdf
Description:
-
Visibility:
Public
MIME-Type / Checksum:
application/pdf / [MD5]
Technical Metadata:
Copyright Date:
-
Copyright Info:
-

Locators

show

Creators

show
hide
 Creators:
Bäumel, Marius1, Author              
Affiliations:
1Majd Al-Naji, Kolloidchemie, Max Planck Institute of Colloids and Interfaces, Max Planck Society, ou_3050472              

Content

show
hide
Free keywords: heterogeneous catalysis, biorefinery, hydrogenation, biomass valorization, carbon support, heterogene Katalyse, Bioraffinerie, Hydrierung, Biomasseverwertung, Kohlenstoffträger
 Abstract: In the present work, a methodology is proposed for the synthesis of metal-based hydrogenation catalysts supported on hierarchically porous carbon pellets, which are suitable for industrial flow processes. For the preparation of the carbon support, durum semolina is used as the carbon source, in addition to ZnO nanopowder as the porogenic templating agent. Owing to their large surface area of 756 m²/g and mesopore volume of 0.49 cm³/g (QSDFT N₂ adsorption), the extruded cylindrical pellets (2.4 × 3.5 mm) offer excellent properties as a support material for highly active catalyst pellets, tailored to the use in large packed bed reactors. The performance of the Ni/C and Pt/C catalysts, prepared with several metal loadings from the support pellets, is investigated in packed-bed flow reactors for two important applications of biomass valorization: the hydrogenation of the bioderived platform molecules 5-hydroxymethylfurfural (HMF) and levulinic acid (LA) to the value-added chemicals 2,5-dimethylfuran (DMF) and γ-valerolactone (GVL), respectively. Aiming at the development of sustainable processes, only water and ethanol are used as green solvents in these processes. In the selective hydrogenation of HMF in ethanol over the synthesized 21wt Ni/C catalyst, a DMF yield of 80.5 (99.0 conversion) is obtained at 150 °C. High catalytic stability is observed during the whole operation period of 33 h. For the hydrogenation of LA to GVL in water at 160 °C, the prepared 2.7wt Pt/C catalyst provides excellent GVL yield of 96.4 (98.9 conversion) and a Pt time yield of 54.7 molGVL/h/molPt (66.2 conversion). With formic acid (FA) as an alternative and renewable hydrogen source, the GVL selectivity was further enhanced to 98.7 (65.3 LA conversion) and a 92.6 GVL yield (97.7 LA conversion) was obtained, using the same type of 2.7wt Pt/C catalyst at 220 °C. The high activity and remarkable selectivity of the FA-assisted hydrogenation demonstrates its potential for a sustainable and self-sufficient integrated refining strategy of sugars to GVL, in which in situ formed FA can be employed as a bioderived reducing agent.

Details

show
hide
Language(s): eng - English
 Dates: 2019-10-012019-11-132019
 Publication Status: Published in print
 Pages: xiii, 131 S.
 Publishing info: Berlin : Technische Universität Berlin
 Table of Contents: -
 Rev. Method: -
 Identifiers: DOI: 10.14279/depositonce-9097
BibTex Citekey: 11303_10109
 Degree: PhD

Event

show

Legal Case

show

Project information

show

Source

show