Development of a New Route for Separating and Purifying 4-Ethyl-2-methoxyphenol Based on the Reaction Mechanism between the Chemical and Calcium Ion.

Based on the characteristic that Ca2+ can react with 4-ethyl-2-methoxyphenol (EMP) to form a complexation with a phenol-calcium ratio of 4:1, a new extraction and purification method of EMP is developed for the first time in this work. At an optimum purification condition, 99.60% purity of EMP can be obtained through a reaction and decomposition operation. By combining a variety of characterizations, which consist of in situ Fourier transform infrared spectrometer (FTIR), nuclear magnetic resonance (NMR), inductively coupled plasma optical emission spectrometer (ICP-OES), gas chromatography-mass spectrometry (GC-MS)/flame ionization detector (FID), elemental analysis, and thermogravimetric analysis, the reaction mechanism of the coordination process is studied. It is demonstrated that there are three stages of the coordination reaction between Ca2+ and EMP. A neutralization reaction occurs in the first stage, while the second stage is a mixing reaction stage including neutralization and coordination reaction. When the reaction proceeds to the third stage, another coordination reaction occurs. Furthermore, phenol and ethanol are added as impurities in EMP. EMP with a purity of more than 99.50% can be obtained using this purification method. It confirms that this efficient method can achieve a good purification effect even for EMP solutions with complicated components.

A novel purification method of activated carbon-supported carbon nanotubes using a mixture of Ca(OH)2 and KOH as the ablation agent.

Transition metals (Fe, Co, Ni) supported on activated carbons with different pore diameters (<2 nm, 10 nm, 50 nm) to synthesize carbon nanotubes (CNTS) are first investigated in this study. Through several characteristic analyses, Ni supported on 50 nm activated carbon is verified to be the most efficient catalyst among the samples for CNT growth. The optimum conditions for CNT growth are at a growth temperature of 750 °C with a reaction time of 45 min. Furthermore, a novel purification method for CNTs is proposed, in which KOH and Ca(OH)2 powder are pre-mixed with the crude CNTs and CO2 and N2 gas are introduced into this mixture. When KOH and Ca(OH)2 powder are used at a ratio of 2 : 1 under the atmosphere of CO2 and N2 at the temperature of 750 °C for 1 h, almost all of the amorphous carbon is ablated. Compared with KOH powder, the addition of Ca(OH)2 not only advances the ablation effect, but reduces the damage to CNTs.

Supported Pd nanoclusters with enhanced hydrogen spillover for NOx removal via H2-SCR: the elimination of "volcano-type" behaviour.

A rational design of a Pd catalyst with highly dispersed Pd nanoclusters on an Al doped ceria-based oxide for low temperature selective catalytic reduction of NOx by hydrogen with excess O2 was achieved. The supported Pd nanocluster shows a high hydrogen spillover ability and a NOx conversion of >84% within 100-300 °C.

Selective production of 4-ethylphenolics from lignin via mild hydrogenolysis.

Selective production of 4-ethylphenolics from lignin via mild hydrogenolysis was reported in this short communication. The hydrogenolysis of lignin was carried out in an autoclave with 65 vol.% ethanol/water as solvent, with 5% Ru/C, Pd/C and Pt/C as catalysts. The influences of catalysts, lignin species, and reaction conditions including reaction temperature, reaction time, and initial H(2) pressure on yield of target compounds were investigated. 3.1% 4-Ethylphenol and 1.3% 4-ethylguaiacol based on lignin could be obtained simultaneously from hydrogenolysis of corn stalk lignin, which is approximate to the yield obtained from petrochemical route. The results of this work showed that this novel method is a quite promising technique for the substitution of petrochemical route.