TY  - JOUR
A1  - Thiel, Alexander
A1  - Tippkötter, Nils
A1  - Suck, Kirstin
A1  - Sohling, Ulrich
A1  - Ruf, Friedrich
A1  - Ulber, Roland
T1  - New zeolite adsorbents for downstream processing of polyphenols from renewable resources
JF  - Engineering in Life Sciences
N2  - Commercial materials with polyvinylpolypyrrolidone and polymeric amberlites (XAD7HP, XAD16) are commonly used for the adsorptive downstream processing of polyphenols from renewable resources. In this study, beta-zeolite-based adsorbent systems were examined, and their properties were compared to organic resins. Batch adsorption experiments were conducted with synthetic solutions of major polyphenols. Adsorption isotherms and desorption characteristics of individual adsorbent were determined based on these results. Maximum adsorption capacities were calculated using the Langmuir model. For example, the zeolites had capacities up to 203.2 mg/g for ferulic acid. To extend these results to a complex system, additional experiments were performed on rapeseed meal and wheat seed extracts as representative renewable resources. HPLC analysis showed that with 7.5% w/v, which is regarded as the optimum amount of zeolites, zeolites A and B could bind 100% of the major polyphenols as well as release polyphenols at high yields. Additionally, regeneration experiments were performed with isopropyl alcohol at 99°C to evaluate how zeolites regenerate under mild conditions. The results showed only a negligible loss of adsorption capacity and no loss of desorption capacity. In summary, it was concluded that beta-zeolites were promising adsorbents for developing new processes to isolate polyphenols from renewable resources.
Y1  - 2013
U6  - http://dx.doi.org/10.1002/elsc.201200188
VL  - 13
IS  - 3
SP  - 239
EP  - 246
PB  - Wiley
CY  - Weinheim
ER  -