TY  - JOUR
A1  - Tippkötter, Nils
A1  - Duwe, Anna-Maria
A1  - Wiesen, Sebastian
A1  - Sieker, Tim
A1  - Ulber, Roland
T1  - Enzymatic hydrolysis of beech wood lignocellulose at high solid contents and its utilization as substrate for the production of biobutanol and dicarboxylic acids
JF  - Bioresource Technology
N2  - The development of a cost-effective hydrolysis for crude cellulose is an essential part of biorefinery developments. To establish such high solid hydrolysis, a new solid state reactor with static mixing is used. However, concentrations >10% (w/w) cause a rate and yield reduction of enzymatic hydrolysis. By optimizing the synergetic activity of cellulolytic enzymes at solid concentrations of 9%, 17% and 23% (w/w) of crude Organosolv cellulose, glucose concentrations of 57, 113 and 152 g L⁻¹ are reached. However, the glucose yield decreases from 0.81 to 0.72gg⁻¹ at 17% (w/w). Optimal conditions for hydrolysis scale-up under minimal enzyme addition are identified. As result, at 23% (w/w) crude cellulose the glucose yield increases from 0.29 to 0.49gg⁻¹. As proof of its applicability, biobutanol, succinic and itaconic acid are produced with the crude hydrolysate. The potential of the substrate is proven e.g. by a high butanol yield of 0.33gg⁻¹.
Y1  - 2014
U6  - https://doi.org/10.1016/j.biortech.2014.06.052
VL  - 167
SP  - 447
EP  - 455
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Hentschke, Reinhard
A1  - Hager, Jonathan
A1  - Hojdis, Nils
T1  - Molecular Modeling Approach to the Prediction of Mechanical Properties of Silica-Reinforced Rubbers
JF  - Journal of Applied Polymer Science
N2  - Recently, we have suggested a nanomechanical model for dissipative loss in filled elastomer networks in the context of the Payne effect. The mechanism is based on a total interfiller particle force exhibiting an intermittent loop, due to the combination of short-range repulsion and dispersion forces with a long-range elastic attraction. The sum of these forces leads, under external strain, to a spontaneous instability of “bonds” between the aggregates in a filler network and attendant energy dissipation. Here, we use molecular dynamics simulations to obtain chemically realistic forces between surface modified silica particles. The latter are combined with the above model to estimate the loss modulus and the low strain storage modulus in elastomers containing the aforementioned filler-compatibilizer systems. The model is compared to experimental dynamic moduli of silica filled rubbers. We find good agreement between the model predictions and the experiments as function of the compatibilizer's molecular structure and its bulk concentration.
KW  - theory and modeling
KW  - supramolecular structures
KW  - rubber
KW  - mechanical properties
KW  - elastomers
Y1  - 2014
U6  - https://doi.org/10.1002/app.40806
SN  - 1097-4628
VL  - 131
IS  - 18
SP  - 1
EP  - 9
PB  - Wiley
CY  - New York, NY
ER  -