Papers by Keyword: Phenol

Abstract: High molecular weight lignosulfonate was oxidatively degrdadated into lower molecular weight fractions, the resulting components were conducted to formulate resol resin with phenol and formaldehyde in an alkaline condition, in which 50% phenol was substituted. The modified resol resin was successfully applied to prepare phenolic foam using appropriate combinations of flowing agents. N-pentane was found to be suitable as the foaming agent. Sulphuric acid (50% aqueous solution, w/w) and Tween-80 were used as catalyst and surfactant, respectively. The obtained foams showed satisfactory mechanical properties and excellent uniform cells, which can comply with the required specifications for its practical utilization.

Abstract: Effective and significant improvement in the technology for the production of phenol has been made over the past decade. New catalysts and processes have been employed to produce a great deal of phenol in the cumene hydroperoxide (CHP) industry. Fire and thermal explosion of CHP has occurred in Taiwan. Therefore, thermal hazard and reactive risk information has been analyzed in this research. Zeolite is employed as a catalyst for the CHP process. The aim of this investigation was to determine the inherent safety of the phenol production process. Effective manufacturing of phenol and safe handling procedures are significant issues for industrial applications. In view of loss prevention, calorimetric application and model evaluations to integrate thermal hazard development are necessary and useful for inherently safer design.

Abstract: The supported Cu/Flokite catalysts were prepared by conventional incipient wetness impregnation. The catalysis oxidation degradation of phenol was carried out in heterogeneous catalyst and H2O2 process. The results indicated that the reaction system with catalyst and hydrogen peroxide was more benefit to degradation of phenol. When the phenol initial concentration was 100 mg/L, the phenol removal over the 2.5%Cu -2.5% Fe/Flokite catalyst could reach 96%. The peroxide catalytic oxidation process over the enhanced heterogeneous catalyst would be a novel technique for the treatment of phenol wastewater.

Abstract: In this work,technological process of the refinement of phenetole by continuous distillation method is introduced and, the effects of reflux ratio, operating pressure and location of feed tray on the distillation process are analyzed. The optimal operating conditions for refining phenetole in laboratory are: operating pressure is 50Kpa, feed tray location is the 35th theoretical plate, total reflux and product outlet location is the 5th plate. The phenetole of high-purity could be obtained with both water and phenol content under 100ppm.

Abstract: Using DFT/6-31+G (d, p) method, the structure of phenol are gained in the global optimization and properties were theoretically studied. The atomic electric charges, activation of reaction and thermodynamics parameters are obtained. The calculation shows that benzene ring in phenol tends to have electrophonic attacking substitution reaction O3 directly and form catechol and hydroquinol. The calculation of thermodynamics properties indicate that two pathways are exothermic reactions, and the Gibbs free energies (ΔG) are always less than zero, two reactions are easily occurred spontaneously. Dynamics calculations show that there is only one transition state in each reaction; through vibrational analysis we confirm the transition state. After corrected single point energy, we find that the reaction activation energies of the two reactions are small (Ea1=4.48kcal/mol and Ea2=2.87kal/mol), indicating that ortho-position and para-position products exist simultaneously, which is in accordance with the thermodynamics calculation result.

Abstract: Removal of low concentration of phenol from aqueous solutions through the adsorption process by using crosslinked β-Cyclodextrin polymer (β-CD polymer) was investigated. The effects of contact time, sodium chloride content, contact temperature and initial concentration of phenol in the aqueous on adsorption capacity were evaluated through a series of batch experiments. The results show that β-CD polymer on the adsorption of phenol balanced after 6h. The adsorption process was apparently influenced by sodium chloride content, contact temperature and initial phenol concentration in aqueous solution. The adsorption behavior for phenol of β-CD polymer is fitted into the Freundlich isotherm.

Abstract: Adopting BYLP method in Density Functional Theory (DFT), we make theoretical study on the ozonide-orthophenylphenol, parachlorophenol, orthobenzoquinone and parabenzoquinone in the two reaction routes of phenol oxidizing into benzoquinone with ozone. We get the geometric configuration of molecules, charge distribution of atoms, thermodynamical properties and frontier orbit energy. Natural Bond Orbital(NBO)charge calculation shows that compared with orthobenzoquinone and parabenzoquinone molecules, phenol, orthophenylphenol and parachlorophenol molecules have stronger reactivity and they are more likely to have electrophilic substitution reaction. Thermodynamic properties indicate that phenol is easy to have oxidation reaction and produce orthophenylphenol which is easily to oxidize into orthobenzoquinone no matter at low temperature, room temperature or high temperature. Another reaction pathwaycalculation shows that in thermodynamics, phenol will not easily ozonize into parachlorophenol; while parachlorophenol will easily ozonize into parabenzoquinone. Frontier orbit energy calculation shows that phenol, orthophenylphenol, and parachlorophenol show similar stability. Orthobenzoquinone and parabenzoquinone have the strongest stability.

Abstract: In order to purify the wastewater polluted by phenol, the research of the thermodynamics of phenol adsorption on the adsorbent was very important. In this paper, a type of crosslinking starch microsphere (SM) has been synthesized by reversed phrase suspension method with soluble starch as raw material and N, N’-methylenebisacrylamide as crosslinking agent. And then the adsorption thermodynamics of SM toward phenol had been studied, and the adsorption capacity increased with the increasing of concentration of phenol solution, lower temperature ccould accelerate adsorption. The research results showed that the adsorption process was exothermic, could proceed spontaneously, and the adsorption driving force came from the enthalpy change mainly. The thermodynamic parameters of adsorption process showed that the adsorption behavior of SM towards phenol belongs to physical adsorption.

Abstract: A aerobic bacterium strain P2 isolated from coking wastewater, was able to utilize phenol, o-cresol and pyridine as its sole carbon and energy source. The morphological properties and the phylogenetic analysis based on 16S rDNA sequences showed strain P2 belonged to the genus Diaphorobacter sp.. The optimum biodegradation of phenol was 37°C, pH 7.0-9.0 and 0.25% NaCl , respectively. The growth arrearage period was prolonged with the phenol concentration. The growth of Diaphorobacter P2 and phenol-degradation were inhibited completely by 50 μmol/L metal ions, such as Cu^{2 +}, Ni²⁺, Cd²⁺ or Cr⁶⁺. Orthogonal experiment indicated the order of metal toxicity to biodegradation of P2 was Zn²⁺>Mn²⁺>Pb²⁺ under various heavy-metal compounds. The phenol biodegradation in coking wastewater supplemented with 2/3 beef extract peptone medium was degraded fully in 3 days, indicating that nutrient solution was beneficial for P2 growth and phenol degradation in wastewater. Those results suggest that the Diaphorobacter P2 has potential for treatment of coking wastewater.

Abstract: The phenol degradation characteristics and immobilization of an Acinetobacte strain HY1 were carried out. The effects of phenol concentration, temperature, pH and NaCl dosage on the growth of HY1 and phenol degradation rate were investigated. The results showed that When the bacteria was cultured in 0.5 g/L phenol solution at 35 °C and pH 7.5 with shaking speed 120 r/min, liquid volume in flask 50 mL and inoculation amount 20 % for 6 h, the degradation rate of phenol was over 95 %. Compared with free bacteria, immobilized bacteria had a higher phenol degradation rate after a long culture time.