生物发酵装置的设计特点

根据某生物工程装置的设计实践 ,介绍了其工艺和管道安装的特点 。

Steam reforming of methane over Ni catalysts prepared from hydrotalcite-type precursors: Catalytic activity and reaction kinetics

Ni/Mg–Al catalysts derived from hydrotalcite-type precursors were prepared by a co-precipitation technique and applied to steam reforming of methane. By comparison with Ni/γ-Al2O3 and Ni/α-Al2O3 catalysts prepared by incipient wetness impregnation, the Ni/Mg–Al catalyst presented much higher activity as a result of higher specific surface area and better Ni dispersion. The Ni/Mg–Al catalyst with a Ni/Mg/Al molar ratio of 0.5:2.5:1 exhibited the highest activity for steam methane reforming and was selected for kinetic investigation. With external and internal diffusion limitations eliminated, kinetic experiments were carried out at atmospheric pressure and over a temperature range of 823–973 K. The results demonstrated that the overall conversion of CH4 and the conversion of CH4 to CO2were strongly influenced by reaction temperature, residence time of reactants as well as molar ratio of steam to methane. A classical Langmuir–Hinshelwood kinetic model proposed by Xu and Froment(1989)fitted the experimental data with excellent agreement. The estimated adsorption parameters were consistent thermodynamically.

Binary Adsorption Equilibrium of Benzene-Water Vapor Mixtures on Activated Carbon

Adsorption equilibrium isotherms of benzene in the concentrationrange of 500-4000 mg·m^-3 on two commercial activated carbons wereobtained using long-column method under 30 deg. C and differenthumidity condi- tions. Results show that the benzene and water vaporshave depression effects upon the adsorption of each other and thatthe unfavorable effect of water vapor resembles its single-componentisotherm on activated carbon. A com- petitive adsorption model wasproposed to explore the depression mechanisms of the non-ideal,non-similar binary adsorption systems.

Sustainable Activated Carbons from Agricultural Residues Dedicated to Antibiotic Removal by Adsorption

The. objectives.of this study are to convert at laboratory s.cale agric.ultural residues into activated carbons （AC） with specific properties, to characterize them and to test them in adsorption reactor for tetracycline removal, a common antibiotic. Two new ACs were produced by direct activation with steam from beet pulp （BP-H2O） and peanut hu_lls （PH-H2O） in environmental friendly conditions BP-H2O and PH-H2Opresentcarbon content rangedcarbons with different intrinsic properties.

One-step fabrication of TiO2/graphene hybrid mesoporous film with enhanced photocatalytic activity and photovoltaic performance

We synthesized a mesoporous film based on TiO2-reduced graphene oxide(RGO)hybrids using a one-step vapor-thermal method without the need for an additional annealing process.The vapor-thermally prepared TiO2-graphene hybrid(VTH)features unique structures with an ultra-large specific surface area of^260 m^2 g^-1 and low aggregation,giving rise to enhanced light harvesting and increased charge generation and separation efficiency.It was observed that a mesoporous film with uniform pore distribution is simultaneously obtained during the VTH growth process.When a 5.0 wt%RGO VTH film was used as the active layer in photocatalysis,the highest photocatalytic activity for degradation of methyl orange was achieved.For another,when a 0.75 wt%RGO VTH film was used as the photoanode in a dye-sensitized solar cell,the power conversion efficiency reached 7.58%,which represents an increase of 73.1%compared to a solar cell using an a photoanode of pure TiO2 synthesized by a traditional solvothermal method.It is expected that this facile method for the synthesis of TiO2/graphene hybrid mesoporous films will be useful in practical applications for preparing other metal oxide/graphene hybrids with ultra-high photocatalytic activity and photovoltaic performance.

SO_2/Hg removal from flue gas by dry FGD

To study the mechanism of SO2 and Hg removal from flue gas, an experimental packed bed reactor was designed to simulate the dry FGD, where a mixture of lime and fly ash in ratio 1：3 w/w was used as the S02 and Hg sorbent, and steam at temperature of 100 ℃ was applied for activation of the sorbent, while the activation time set to 20 rain. The experimental factors including the SO2/Hg sorbent characteristics, 50% breakthrough time for SO2/Hg removal, sorbent packed bed depth and reaction temperature were investigated. The experimental results show that after steam activation, the BET specific surface area and specific pore volume increased from 37.8 to 45.5 m^2/g and from 0.42 to 0.51 cm^3/g, respectively. With activation of the sorbent by steam, the 50% breakthrough times of SO2 and Hg removal increased from 34 to 42 rain and from 23 to 45 rain, respectively. When the packed bed depth was increased from 5 to 25 ram. the 50% breakthrough times for Hg and S02 removal increased from 12 to 52 rain and from 6 to 47 rain, respectively. With the increase of the reaction temperature, the 50% breakthrough of SO2/Hg removal decreased accordingly. Steam activation can efficiently improve SO2/Hg removal simultaneously.

Isobaric Vapor-Liquid Equilibrium for Toluene, 3-Methylthiophene and N-formylmorpholine at 101.33 kPa

Isobaric vapor-liquid equilibrium (VLE) data were measured for binary mixtures of toluene+N- formylmorpholine, toluene+3-methylthiophene and 3-methylthiophene+N-formylmorpholine at 101.33 kPa. The VLE data of the binary systems were found to be thermodynamically consistent. The saturated vapor pressure calculated by CSGC-PR equation of the pure component had higher accuracy than that calculated by Antoine equation. The liquid- phase activity coefficients of the binary systems were calculated by the Wilson, NRTL and UNIFAC models, and the binary interaction parameters of the three models were determined by the VLE data. The Wilson model was selected as the most suitable model to predict the VLE data of the ternary system of toluene+3-methylthiophene+N- formylmorpholine. The relative volatility between toluene and 3-methylthiophene was also calculated. Moreover, the effect of N-formylmorpholine as solvent was studied. When the molar ratio of solvent to feed (S/F) was 7, the relative volatility reached 1.904, which is almost twice the relative volatility without solvent. Therefore, N-formylmorpholine can be considered as an effective extracting agent for the separation of the close-boiling mixture of toluene+3- methylthiophene by extractive distillation.

A simplified adsorption model for water vapor adsorption on activated carbon

A simplified model was developed to describe the water vapor adsorption on activated carbon. The development of the simplified model was started from the original model proposed by DO and his co-workers. Two different kinds of carbon materials were prepared for water vapor adsorption, and the adsorption experiments were conducted at different temperatures(20-50 °C) and relative humidities(5%-99%) to test the model. It is shown that the amount of adsorbed water vapor in micropore decreases with the temperature increasing, and the water molecules form larger water clusters around the functional group as the temperature is up to a higher value. The simplified model describes reasonably well for all the experimental data. According to the fitted values, the parameters of simplified model were represented by the temperature and then the model was used to calculate the water vapor adsorption amount at 25 °C and 35 °C. The results show that the model can get relatively accurate values to calculate the water vapor adsorption on activated carbon.

Extended XG Equation for the Prediction of Adsorption Equilibrium of Vapor Mixture on Activated Carbon

The XG equation, which is developed by us previously for describing the adsorption equilibrium of pure vapor on activated carbon, is extended to multi-component system. Verified by experimental data, the extended XG equation was found to be more successful in predicting the adsorption equilibrium of vapor mixture on activated carbon than the extended Langmuir equation, the extended BET equation and the ideal adsorbed solution theory (IAST).

Comparison of Distillation Methods of Mentha cordifolia Opiz, Essential Oil on Antibacterial Activity for Application Use in Animal Feeds

This study was conducted to evaluate the effect of different distillation methods of Mentha cordifolia Opiz. essential oil on antibacterial activity. The essential oils were isolated by water and steam, hydro, ethanol, and 3methanol： lethanol distillations. Moreover, we also compared the efficacy of these various distillations with commercial peppermint oil. Essential oils were tested in vitro against three pathogen bacteria species by sensitivity test include disc diffusion assay （DD）, minimal inhibition concentration （MIC） and maximal bactericidal concentration （MBC）. Escherichia coli, Staphylococcus aureus and Salmonella typhimurium were used in this investigation. The results showed that the water and steam distillation and 3methanol： lethanol under tested by DD assay was found to be effective against all the pathogenic bacteria, in which the zone of inhibition exhibited E. coil S. aureus and S. typhimurium were 9.67 ± 0.35, 11.67 ± 0.66, 18.0± 1.15 and 9.00 ± 0.05, 8.3 ± 0.35, 19.0 ± 0.00 ram, respectively. While the hydro and ethanol distillations did action to against only E. coli which the inhibition zones were 8.67 ± 0.66 and 8.67 ± 0.35 mm, respectively. However, the commercial oil was more effective against tested pathogenic bacteria than all M. cordifolia essential oil. In case of MIC and MBC assays, the results showed that all essential oil distillation methods posed antibacterial potential in which the water and steam distillation showed the lowest MIC and MBC values against E. coli, S. aureus and S. typhimurium. It is suggested that among all M. cordifolia essential oil extractions, water and steam distillation was found to be highly bactericidal as it has shown in lowest MIC and MBC values and high in growth inhibition zone diameter.

Water vapor adsorption in activated carbon modified with hydrophilic organic salts

Five different kinds of hydrophilic organic salts were used to modify commercial activated carbon in order to prepare hydrophilic carbon materials. Properties of the samples were analyzed by surface area analyzer and SEM-EDX. The hydrophilic organic salts with different properties were introduced into activated carbon and significantly affected the properties of the samples.During adsorption experiments, the water vapor adsorption amount in modified samples increases by 0.57-17.12 times in temperature range from 303 to 323 K and at relative pressure below 0.50. Water molecules combined with surface hydrophilic groups through H-bonding exhibit good thermo stability. The effects of temperature, oxygen content and properties of the hydrophilic organic salts on water vapor adsorption were studied. It is indicated that water vapor adsorption in modified samples is mainly affected by the surface oxygen content. The carboxylate radicals in the hydrophilic organic salts greatly affect the micropore structure of the modified samples, while the metal ions in them exhibit limited influence. Different adsorption capacity of modified samples can be explained with the electronegativity of elements presented by Pauling.

GeoQuest Project Computer Class Role Playing Game as Innovative Teaching Methodology to Foster STEAM Education

GeoQuest Project is the design of a new teaching and learning technology based on Computer Class Role Playing Games （RPG） to teach Earth Science in a STEAM educational approach. It ensures interdisciplinarity, multilinguai approach （CLIL compliance） and interactive activities in classrooms. This educational game uses students＇ personal tablets and smartphones to interact with the game, with a system more comprehensible and funny for young people compared to traditional methodologies. Students are bringing ＂in situation＂ by the adventure, so teachers can get a rigorous assessment of their skills. The Game includes several adventure paths, suitable for different age students. They are focused on scientific topics, humanities, hands-on activities in interdisciplinary way. If used conditions do not allow practical or laboratorial activities provided by the game, players can see some videos to understand the activities. Experimental results were outstanding： the RPG appreciation is in agreement with the experiments outcome. This work experience gets excellent feedbacks by teachers, in terms of efficacy of this new teaching methodology and of results achieving.

Structural properties of hydroxyl-substituted alkyl benzenesulfonates at the water/vapor and water/decane interfaces

Molecular dynamics simulations have been performed to investigate the structural properties of hydroxyl-substituted alkyl benzenesulfonate monolayers formed at the water/vapor and water/decane interfaces.We report a detailed study of the interfacial properties-liquid density profile,hydrogen bond structure,surfactant aggregate structure and order parameter-of the novel anionic surfactant,sodium 2-hydroxy-3-decyl-5-octylbenzenesulfonate(C10C8OHphSO3Na).Simulation results show that:with increasing number of surfactant molecules,the average number of intramolecular hydrogen bonds per surfactant molecule in the monolayer decreases,but the structures forming the intramolecular hydrogen bonds still play a dominant role;the hydrophobic part of the alkyl tail chain,especially the decyl substituent on the third carbon atom in the benzene ring,becomes straighter,and more ordered towards the external interface at higher surfactant coverage;two-dimensional radial distribution functions can describe the characteristic of surfactant aggregate structures and highlight the decane phase effect on the orientation of the hydrophobic part of the surfactant;the surfactant molecules readily form long-range hydrogen bonded structures.Our results are an important complement to experimental studies.We used the all-atom model by employing the GROMACS and ffAMBER programs in the simulations,which provides a new way to simulate the interfacial behavior of alkyl benzenesulfonate surfactants.

Molecular catalysis for the steam reforming of ethanol

In this paper, the application of molecular catalysis for steam reforming of ethanol （SRE） is reviewed. Eight metals （Ni, Co, Cu Pt, Rh, Pd, Ir and Ru） have shown high catalytic activity for SRE. Among them Ni and Rh are very promising because of high d character in the metal bond and low metal-oxygen bonding （vs. metal-carbon）. They can effectively promote C-C bond cleavage in the rate-determining process during SRE. However, Rh is weak in water-gas-shift so that CH4 and CO become the main by-products at low reaction temperatures, while Ni catalysts suffer from rapid deactivation due to coking and sintering. Two low-temperature CO-free catalysts have been developed in our lab, namely Rh-Fe/Ca-Al2O3 and carbonyl-derived Rh-Co/CeO2, in which the presence of iron oxide or Co can promote water-gas-shift reaction and significantly improve the SRE performance. On the other hand, adding 3 wt% CaO to Ni/Al2O3 can greatly improve the catalyst stability because the Ca modification not only increases Ni concentration on the Ni/Ca-Al2O3 surface and 3d valence electron density, but also facilitates the water adsorption and coke gasification via water-gas-shift. The availability of abundant surface OH groups helps the formation and conversion of adsorbed formate intermediate. Hence, ethanol reaction on Ca-Al2O3-supported Ni, Pt, Pd and Rh catalysts are found to follow the formate-intermediated pathway, a new reaction pathway alternative to the traditional acetate-interrnediated pathway.