Adsorption kinetics, thermodynamics and isotherm of Hg(II) from aqueous solutions using buckwheat hulls from Jiaodong of China.

The adsorption kinetics and adsorption isotherms of buckwheat hulls in the region of Jiaodong, China (BHJC) for Hg(II) were investigated. Results revealed that the adsorption kinetics of BHJC for Hg(II) were well described by a pseudo second-order reaction model, and the adsorption thermodynamic parameters ΔG, ΔH and ΔS were -5.83 kJ mol(-1)(35°C), 73.

Biosorption of heavy metal ions onto agricultural residues buckwheat hulls functionalized with 1-hydroxylethylidenediphosphonic acid.

Novel biosorbent materials obtained from agricultural residues buckwheat hulls (BH) were successfully developed through functionalization with 1-hydroxylethylidenediphosphonic acid (HEDP), and they were characterized. This paper reports the feasibility of using HEDP-BH for removal of heavy metals from stimulated wastewater, the experimental results revealed that the adsorption property of functionalized buckwheat hulls with 120 mesh 120-HEDP-BH for Au(III) was very excellent, and the monolayer maximum adsorption capacity for Au(III) calculated from the Langmuir isotherm models was up to 450.45 mg/g at 35 °C.

Production of biodiesel by esterification of oleic acid with ethanol over organophosphonic acid-functionalized silica.

Esterification of oleic acid with ethanol catalyzed by organophosphonic acid-functionalized silica SG-T-P was optimized using response surface methodology (RSM). The interactive effect of catalyst to FFA weight ratio and molar ratio of alcohol to acid were more significant than that of reaction temperature. The optimum values for maximum conversion ratio obtained by a Box-Behnken center-united design reached 77.