J.-G. Zhao

An Au–Cu bimetal catalyst for acetylene hydrochlorination with renewable γ-Al2O3 as the support

The bimetal catalyst gold(III) chloride–copper(II) chloride (AuCl3–CuCl2) was prepared with several different gamma-aluminium oxide (γ-Al2O3) supports and its catalytic properties towards acetylene hydrochlorination were assessed in a fixed-bed reactor. The comparison indicated that one of the catalysts attained the highest activity with an acetylene conversion of 97%, which was far higher than the others. Catalysts were characterized using detailed X-ray diffraction, nitrogen-Brunauer, Emmett and Teller surface area analysis (N2-BET), ammonia temperature-programmed desorption, Fourier-transform infrared spectroscopy and carbon dioxide temperature-programmed desorption analysis. It is proposed that the base site contributed to its high catalyst activity compared with the other catalysts, instead of the acid site or the textural properties on the support, therefore, the activity and the life of the catalysts can be improved significantly by treating the supports with potassium hydroxide. In addition, the results of N2-BET, thermogravimetric analysis and scanning electron microscopy indicated that the catalysts deactivated rapidly because of carbon deposition, and the actual amount of coke deposition was 18.0% after the reaction. AuCl3–CuCl2/γ-Al2O3 was easily regenerated for reuse as a catalyst by burning off in an air atmosphere for 10 min. The activity of the regenerated catalyst nearly reached the level of the fresh catalyst.

Using Titanium Alkoxide Complex to Synthesize TS-1 and Their Catalytic Performance for Propylene Epoxidation

Abstract Titanium alkoxide complex as titanium source, silica gel as silica source, TPABr as templating agent have been used to synthesize titanium silicalite-1 (TS-1). In contrast to the commonly used Ti alkoxides, the titanium alkoxide complex will be very stable in water at room temperature, which offers considerable advantages when compared to conventional synthesis routes. By XRD and IR results, it was shown that titanium can be incorporated into the silicalite framework up to an extent about 2.3% (mol) Ti/(Ti+Si) without extra framework. In batch experiment, with TS-1 as propylene epoxidation catalyst, the conversion of hydrogen peroxide and the selectivity for propylene oxide are higher than 96%. Aging test on extruded TS-1 catalyst were carried out in a continuous-flow fixed bed reactor, it was concluded that synthesized TS-1 has the good catalytic performance and stability.

A Study on the Prediction Model for the Lubricity of Hydrogenated Ultra-low Sulfur Diesel Fuel

Abstract The physicochemical properties of hydrogenated diesel fuel and its fractions produced by hydro-refining, hydro-upgrading, and hydro-cracking were analyzed. The lubricity of diesel fuel and its fractions were measured by a high-frequency reciprocating rig. The relationships of lubricities between the fractions were discussed. The prediction model for the lubricity of hydrogenated diesel with a sulfur content below 200 μg/g was established by using the stepwise linear regression method. The coefficient, R, reached up to 0.981, and the relative error of the predicted value to the actual value was less than 7%. According to the coefficients of the prediction model, the lubricity of ultra-low sulfur diesel with high kinematics viscosity, high nitrogen content, and low cycloparaffins content under the condition of deep hydrogenation was relatively inferior. The model could well predict the lubricity of the ultra-low sulfur diesel fuel and hydro-fining diesel fuel.

Research on Reactive Adsorption Desulfurization Over Metal Oxides Adsorbent

Reactive adsorption desulfurization over metal oxides adsorbents was carried out to remove the sulfur of real fluid catalytic cracking gasoline and model gasoline in a batch reactor at low pressures in the presence of hydrogen. The results show that Ni appearing after reduction and higher temperature leads to a significant improvement in the desulfurization ability of the adsorbents. When the initial concentration of thiophene in the model gasoline raised the sulfur, removal rate decreased while the adsorption capacity of the adsorbents increased and the maximum sulfur removal rate and sulfur adsorption capacity were 86.33% and 13.72 mg/g, respectively.

Improving the Solvent Deasphalting Process by the Co-treating of Residue and Coal

In view of the harsh conditions of coal liquefaction and the difficulty of residue processing, through medium- and low-temperature heat treatment of vacuum residue with coal, the solvent deasphalting process of residue treated with coal was studied. The results showed that particle size, types, adding amount of coal, and contacting temperature of residue with coal had effects on the solvent deasphalting process. Compared with the solvent deasphalting process of residue directly, coal particle size in 150–830 μm, coal/vacuum residue in 3:10–3:4 at 250°C, the yield of deasphalted oil could increase by 2.6–3.5 wt%, the removal rate of metals, such as nickel and vanadium, were 24.7 and 23.07%, respectively. The content of sulfur and carbon residue in deasphalted oil decreased slightly. Deasphalted oil had a higher yield and better quality when the contacting condition of residue and coal was harsher. The study demonstrated that the solvent deasphalting process could be improved by co-treating of residue and coal under medium and low temperature.

Kinetics of Reactive Adsorption Desulfurization of Thiophene in n-Hexane over Oxides Adsorbent of NiO/ZnO-Al2O3-SiO2

The oxides adsorbent of NiO/ZnO-Al2O3-SiO2 was prepared by a co-precipitation method. The adsorbent can be used for the desulfurization of thiophene in n-hexane as model gasoline. Conditions of the reactive adsorption desulfurization in model gasoline were studied. Adsorption kinetics were found to follow a pseudo-first-order better than pseudo-second-order model. Equilibrium isotherms for the adsorption of thiophene over metal oxides adsorbents were analyzed by Freundlich and Langmuir isotherm models using a non-linear regression method. Further, Langmuir isotherm represented the equilibrium adsorption data best at all temperatures.

Reactive Adsorption Desulfurization of FCC Gasoline over NiO/ZnO-Al2O3-SiO2 in a Fixed-fluidized Bed Reactor

The oxides adsorbent of NiO/ZnO-Al2O3-SiO2 was prepared by a co-precipitation method. NiO/ZnO-SiO2-Al2O3 is an effective adsorbent for reactive adsorption desulfurization of fluid catalytic cracking gasoline. The reaction conditions, such as reaction temperature, total pressure, weight hourly space velocity, and volume ratio of hydrogen to oil for desulfurization over NiO/ZnO-SiO2-Al2O3 in a fixed-fluidized bed reactor were investigated. With the optimum conditions, the sulfur content of FCC gasoline can be decreased from 180 to 11.6 mg·L−1, and the loss of olefin content of gasoline product is 1.05%, the research octane number loss of gasoline product is only 1.3 unit.

Prediction of the Styrene Butadiene Rubber Performance by Emulsion Polymerization Using Backpropagation Neural Network

The effect of the amounts of initiator, emulsifier, and molecular weight regulator on the styrene butadiene rubber performance was investigated, based on the industrial original formula. It was found that the polymerization rate was increased with the increased dosage of initiator and emulsifier, and together with replenishing molecular weight regulator will make the Mooney viscosity of rubber meet the national standard when the conversion rate reaches 70%. The backpropagation neural network was trained by the original formula and ameliorated formula on the basis of Levenberg-Marquardt algorithm, and the relative error between the simulation results and experimental data is less than 1%. The good consistency shows that the BP neural network could predict the product performances in different formula conditions. It would pave the way for adjustment of the SBR formulation and prediction of the product performances.

The Effect of Flux on the Melting Characteristics of Coal Ash from the Liu-qiao No. 2 Coal Mine in North Anhui Province

Abstract The effect of flux on the melting characteristics of coal ash from the Liu-qiao No. 2 Coal Mine in north Anhui province (AQ) was investigated. The change of the compositions of mineral under various temperatures with the atmosphere of N2 and H2 mixture before and after adding flux into AQ was analyzed by infrared ray. Results show that mullite formed over 1000°C has an effect on increasing the ash fusion temperature of coal, and this is the major reason that leads to a high ash fusion temperature of AQ. The coal ash fusion temperature was obviously reduced by adding calcium-based flux, magnesium-based flux, and ferrum-based flux, respectively. While the added mass amount of calcium-based flux is 6.2% (coal as reference), or the added mass amount of magnesium-based flux is 2.8%, the ash fusion temperature of AQ could be reduced to below 1350°C to meet the requirements of the shell gasifier slag-tapping process. The low temperature eutectic mixtures are easily formed between flux with aluminium silicate minerals under high temperatures, which will remarkably decrease the coal ash fusion temperature.

A Study on Selective Catalytic Oxidation Desulfurization of Thiophene in Imitation Gasoline with Ti-MCM-41/H2O2·HCOOH

Abstract The selective oxidative desulfurization was conducted with a feedstock of model gasoline consisting of thiophene and n-octane in an H2O2·HCOOH oxidative system over a Ti-MCM-41 catalyst. The operations were designed by the orthogonal design method with an L9 (34) table. Experimental results show that the factors influencing the rate of desulfurization are reaction temperature, the reaction time, and the volume percent content of the hydrogen peroxide in order. Under the optimized operation conditions over Ti-MCM-41 catalyst: H2O2 volume fraction of 3% (v), reaction time of 40 min and reaction temperature of 50°C, the removal ratio of thiophene was 95.6%, and the gasoline yield was 98.7%. The activity of the catalyst has no dramatic deactivation after reusing it five times. In addition, the kinetics study indicates that this reaction is a pseudo first-order reaction with the activation energy of Ea = 40.18 kJ/mol.