Preparation of Starch-Hard Carbon Spherules from Ginkgo Seeds and Their Phenol-Adsorption Characteristics
AbstractCarbon spherules from ginkgo seed starch were prepared through stabilization and carbonization processes. The ginkgo seed starch was first stabilized at 195 °C for 18 h, then carbonized at 500 °C for 2 h under an N2 atmosphere. The characterization results confirmed that carbon spherules were in the size range of 10–20 μm. Experimental data were also evaluated to find out the kinetic characteristics of phenols on the carbon spherules during the adsorption process. Adsorption processes for phenol, p-nitrophenol and p-chlorophenol were found to follow the pseudo-first order kinetic model with R2 values of 0.995, 0.997 and 0.998, while the rate constants k1 = 0.014, 0.009 and 0.011 min−1 showed that the adsorption is mainly controlled by adsorbate diffusion. The equilibrium data were analyzed with the Langmuir, Freundlich and Temkin–Pyzhev models and the best fit was observed with the Freundlich isotherm, suggesting the physical adsorption of phenols. From the thermodynamic functions, ∆G, ∆H, and ∆S were calculated, which showed that adsorption is more favorable at low temperature and is an exothermic process, and the adsorption of p-nitrophenol and p-chlorophenol were more advantageous than that of phenol. View Full-Text
Share & Cite This Article
Chen, H.; Wang, C.; Ye, J.; Zhou, H.; Tao, R.; Li, W. Preparation of Starch-Hard Carbon Spherules from Ginkgo Seeds and Their Phenol-Adsorption Characteristics. Molecules 2018, 23, 96.
Chen H, Wang C, Ye J, Zhou H, Tao R, Li W. Preparation of Starch-Hard Carbon Spherules from Ginkgo Seeds and Their Phenol-Adsorption Characteristics. Molecules. 2018; 23(1):96.Chicago/Turabian Style
Chen, Hongxia; Wang, Chengzhang; Ye, Jianzhong; Zhou, Hao; Tao, Ran; Li, Wenjun. 2018. "Preparation of Starch-Hard Carbon Spherules from Ginkgo Seeds and Their Phenol-Adsorption Characteristics." Molecules 23, no. 1: 96.
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.