3 research outputs found
Adsorption of Phenylethyl Alcohol onto Granular Activated Carbon from Aqueous Solution: Kinetics, Equilibrium, Thermodynamics, and Dynamic Studies
Comparative
studies were performed toward adsorption kinetics and
equilibrium of phenylethyl alcohol (PEA) onto three typical types
(F400D, CAL, and 207CX) of granular activated carbons (GAC). The effective
diffusion coefficients were of the order of 10<sup>–12</sup> m<sup>2</sup>·s<sup>–1</sup> for PEA adsorption on the
GAC at 298 K. Desorption ratios of PEA from GAC were 92.2–99.9%
achieved by methanol in batch mode at 298 K. Among the GAC employed,
the carbon CAL proved to be superior in terms of physical properties
as well as adsorption capacity and rate toward PEA. Dynamic adsorption
was investigated using this optimal activated carbon. The maximum
bed saturation capacity toward PEA was 2.471 mmol·g<sup>–1</sup> under optimal conditions (GAC mass 10.01 g, inlet concentration
4.391 mmol·kg<sup>–1</sup>, flow rate 6.5 × 10<sup>–3</sup> kg·min<sup>–1</sup>, temperature 298
K). The Yoon-Nelson model best described breakthrough data of PEA
on GAC bed, whereas Yan and Clark models gave a relatively poor fit.
The outcome of this work will facilitate adsorptive recovery of PEA
from rose hydrolate byproduct using GAC
Chemical composition of essential oils and hydrosols from fresh flowers of <i>Cerasus subhirtella</i> and <i>Cerasus</i><i>serrulata</i> from East China
<div><p>Essential oils and hydrosols from fresh flowers of <i>Cerasus subhirtella</i> (Miq.) Sok. and <i>Cerasus</i><i>serrulata</i> (Lindl.) London from East China were analysed by gas chromatography and gas chromatography–mass spectrometry for the first time. The major components of the essential oils from <i>C. subhirtella</i> and <i>C.</i><i>serrulata</i> were benzaldehyde (31.2% and 42.1%, respectively), tricosane (23.1% and 27.7%, respectively) and pentacosane (23.2% and 19.0%, respectively). The main constituents of the hydrosol volatiles from <i>C. subhirtella</i> and <i>C.</i><i>serrulata</i> were benzaldehyde (67.5% and 64.3%, respectively) and mandelonitrile (12.5% and 12.4%, respectively). Benzaldehyde was the key component of the essential oils, while benzaldehyde as well as mandelonitrile was the principal compound of the hydrosols.</p></div
The Manufacture of a Homochiral 4‑Silyloxycyclopentenone Intermediate for the Synthesis of Prostaglandin Analogues
A process is described for the synthesis of kilogram
quantities
of homochiral 4-silyloxycyclopentenone (<i>R</i>)-<b>1</b>, a key intermediate useful for the synthesis of a plurality
of prostaglandin analogue drugs. Cyclopentenone (<i>R</i>)-<b>1</b> was synthesized in 14 isolated steps from furfural.
Key steps in the synthesis include a Wittig reaction, Piancatelli
rearrangement, and an enzymatic resolution featuring in situ recycling
of the undesired enantiomer furnishing the desired homochiral alcohol
in ≥99.5% ee. As a retort to the unsatisfactory coformation
of about 8% at best of the <i>trans</i>-olefin in the Wittig
reaction, a change to the order of several steps and the identification
of a recrystallisable, amine salt derivative, <b>2</b>, allowed
the unwanted isomer to be controlled to as low as 0.2%