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In order to separate In(III) and Fe(III) from the sulfate leaching solution, solvent extraction with Di-2-ethylhexylphosphoric acid (D2EHPA) was investigated using a Impinging Stream–Rotating Packed Bed (IS–RPB) contactor in laboratory scale. The effects of operating parameters, such as feed solution pH, flow rate ratio, the high gravity factor, the concentration of D2EHPA, initial iron concentration, stripping solution concentration were examined. The experimental results showed that the IS–RPB was effective in the separation of In(III) and Fe(III)under favorable operating conditions. The extraction and stripping efficiency as high as 99% could be achieved, at a separation factor in excess of 3000. Compared with other mixing devices, IS–RPB contactor has better micromixing characteristics, which has a good application prospect.

Bamboo as the raw material is carbonized to prepare high specific surface area activated carbon by microwave heating under nitrogen atmosphere in our present work. Influences of activation agents on the preparation of activated carbon are studied. The results show that activation agents have a significant influence on the preparation of activated carbon. Under the heating time of 15 min, the adsorption capacity of the activated carbon prepared utilizing KOH as activation agent is the best. When the KOH/C ratio is 4, the iodine number and yield of activated carbon are 2298 mg/g and 39.82%, respectively. The BET specific surface area, total pore volume and average pore diameter of activated carbon are 3441 m2/g, 2.093 ml/g and 2.434 nm, respectively. The micropore volume of 1.304 ml/g is 62.30% of total pore volume, indicating that the activated carbon is microporous activated carbon.

High gravity technology is an efficient process intensification technology. Its applications in the chemical, materials and other industries have been relatively mature. The basic principles, characteristics and development of this technology are firstly summarized in this paper. And then, its basic theory researches and engineering applications are comprehensively analyzed. Finally, aiming at the liquid extraction problems in metallurgy industry, the application prospects and problems to be solved were put forward.

The effect of ZnO dosage, iron remover and the time duration of neutralization and iron-precipitation on iron removal percentage was investigated to find out the optimal parameters in the technique of ZnO pressurization, neutralization and iron removal, and the residual acid from pressurization lixiviation and neutralization was assayed by using ZnO ore to neutralize and remove iron from lixiviated mineral pulp containing residual acid 20 g/l by simulation of Zn concentrate pressurization and lixiviation in a 2 L autoclave, in order to simplify Zinc pressurization process. The result showed that when Zn lixiviation percentage is higher than 98 %, up to 99.74 % of iron in the lixiviation fluid could be precipitated and the lixiviated fluid contains iron at the level of 20 mg/l, meeting the requirement on pre-purification fluid. Keywords: Zinc Sulfide Concentrate; Pressurization and Lixiviation; ZnO Ore; Neutralization and Iron Precipitation

Theoretical studies on a series of binuclear transition metal pentazolides M2(N5)4(M=Co, Rh and Ir) predict Paddlewheel-type structures with very short metal-metal distances suggesting high-order metal-metal multiple bonds. Natural Bonding Orbital (NBO) analysis have indicated that the bonding between the metal atom and the five-membered ring is predominantly ionic for each M2(N5)4species, and a high-order metal-metal multiple bonding exists between the two metal atoms, in addition, the presence of the delocalized π orbital plays an important role in the stabilization of this metal-polynitrogen species. Nucleus independent chemical shift (NICS) values confirm that the planar N5exhibits aromaticity in these M2(N5)4species. The values of NICS(0.0), NICS(0.5) and NICS(1.0) for Co2(N5)4are larger than those of the other two M2(N5)4species (M=Rh and Ir), with the order of Co2(N5)4>Rh2(N5)4>Ir2(N5)4. The dissociation energies into Mononuclear Fragments for M2(N5)4(M=Co, Rh and Ir) are predicted to be 82.9 (85.7), 139.9 (113.2), and 155.1 (149.7) kcal/mol, respectively. However, the dissociation energies for the loss of one pentazolato group from the M2(N5)4analysis have indicated that the Co2(N5)4is relatively higher at ~40 kcal/mol. Thermochemistry suggests Co2(N5)4to be a viable species.

The present study measures dielectric properties (e´, e″ and tanδ) of zinc oxide dust produced in a rotary kiln, using a cavity perturbation method with microwaves at 2.45 GHz. The effect of apparent density of the dust on the dielectric properties was determined. The results indicated that zinc oxide dust has excellent absorbing performance and can reach 800 oC in 6 minutes. The apparent density of zinc oxide dust and the microwave penetration depth were also related.

During metallurgy and food processing it is always necessary for real-time detection of stereo temperature distribution in reaction cavity of microwave. We focus on the stereo reconstruction of temperature distribution of the microwave reaction chamber using real-time image data captured by infrared sensor during heating process. Due to the stereo depth of the scene in humans vision system is mapped through disparity, thus the key technology stereo reconsturction of temperature is to find the corresponding points in the image pair. We employ the block matching algorithm to search the correspondence by minimizing a cost function derived on a hierarchical tree structured pyramid probabilistic graph. The study result shows that in the back projection of the depth map, the walls, ceiling, and floor of the microwave reactor all appear mutually orthogonal, which illustrates that the stereo temperature field is well reconstructed.

The technology that CuCl residue from Zn hydrometallurgy was dried by microwave heating was studied. The influence of the drying duration, drying temperature and material thickness on dehydration rate was investigated. The response surface methodology (RSM) technique was utilized to optimize the process conditions. The optimum conditions for drying CuCl residue have been identified to be an drying temperature of 80°C, drying duration of 11 min and material thickness of 16 mm. The optimum conditions resulted in an CuCl residue with moisture content of 4.97%, which could ensure remove chlorine of CuCl residue by microwave roasting.

In this paper, furfural was produced from hemicelluloses of bagass by hydrolization reaction with sulfuric acid and acetic acid respectively. The effect of several variables such as temperature , liquid-to-solid ratio ,time and catalyst charge（KCL） on furfural yield was studied. The results showed that the better yield of furfural was obtained in acetic acid hydrolysis system. However, compared to yield of acetic acid hydrolysis system, it need more time and higher temperature at the same liquid-to-solid ratio. At last, when sulfuric acid as catalyst, liquid-to-solid ratio was 1:6 and time was 5h at 150°C, furfural yield can reach 75 %.

On the premise of biomass comprehensive using concept, the screw section liquid of aspen APMP was treated by alcohol precipitation method to separate and analyze the hemicelluloses. In the traditional alcohol separation system, not only the effect of the temperature, alcohol dosage, pH value and precipitation time on the hemicelluloses separation was researched, but also the methanol system and alcohol-CPAM system were discussed. The results showed that the hemicelluloses yield was relatively ideal when the AMPM liquid was treated by 2.5 times volume of alcohol at pH of 4.0 at 45°C for 30 min. In addition, compared with alcohol system, the methanol dosage was decreased by about 12% in methanol system and the alcohol dosage was also decreased In the alcohol-CPAM system, when the hemicelluloses yield was similar.

A novel method for preparation of iron oxyhydroxide materials, involving aqueous precipitation followed by microwave assisted aging is investigated. The produced materials are characterized by XRD, SEM, EDX and TEM spectroscopy and BET analysis. The materials show physical characteristics dependent on preparation procedure. The adsorptive properties of the materials for arsenic are studied by batch adsorption techniques. It is found that the rate of arsenic upload depends strongly on the degree of crystallinity of the materials. The adsorption capacity is approximately 55 mg/g. The physical characterization of the arsenic loaded adsorbents show that the adsorption process modifies the morphology of the materials. Over 4% of arsenic atoms are incorporated into the particle matrix.

An Agilent E4980A precision the LCR meter was used to estimate the effect of frequency, moisture content, position, location and variety on dielectric properties for biomass material of tobacco stems at microwave frequency of 2MHz. The dielectric properties of tobacco stems were significantly affected by frequency and moisture content. Both dielectric constant and dielectric loss factor rapidly declined first and then slowed with increasing frequency at lower moisture content. Increasing the moisture content, dielectric constant increased with the increasing frequency by orders of magnitude, while dielectric loss factor increased first and then decreased with dielectric relaxation emerging, where the dipolar relaxation frequency and the max of the dielectric loss factor also increased. Dielectric properties of the biomass material of tobacco stem were also affected by position, location and variety to some degree. The dielectric properties variation of K326 and Yun 87 was similar to each other which reflected their same genetic characteristics. At the frequency of 2MHz, dielectric constant and dielectric loss factor were mainly at 50-100 and 0.005-0.020, respectively.

In this paper, the hemicelluloses extraction of bagasse with NaOH/borax was studied, and some parameters which may affect the hemicelluloses yield and properties were discussed, such as alkali charge, borax charge, liquid-to-solid ratio, temperature and time of extraction. The compositions and characteristics of hemicelluloses were analyzed by FT-IR, GC, GPC. The results showed that compared with the conventional alkali extraction, the hemicelluloses dissolution rate was increased and degradation degree of the hemicelluloses was decreased with NaOH/borax. When the alkali charge was 65%(based on NaOH)and borax charge was 7% at a liquid-to-solid ratio of 15:1 at 90 °C for 180 min, the dissolution rate of hemicelluloses up to 84.5% (to the hemicelluloses content in material).

The mullite whiskers were synthesized from commercial raw materials by sintering in air. Three factors influencing the aspect ratio of whiskers, including sintering temperature, holding time and addition amount of V2O5, were analyzed based on single factor design and response surface methodology respectively. The optimum conditions for the synthesis of mullite whiskers with highest aspect ratio was obtained, i.e. sintering temperature was 1316.87°C, addition amount of V2O5 was 4.09wt.% and holding time was 1.96h. The experiment at the optimum condition was conducted and the real experimental value agrees to the predicted value based on response surface methodology.

The process parameters of one step preparation of ZnO/Activated Carbon (AC) composite materials, from vinyl acetate synthesis spent catalyst were optimized using response surface methodology (RSM) and the central composite rotatable design (CCD). Regeneration temperature, time and flow rate of CO2 were the process variables, while the iodine number and the yield were the response variables. All the three process variables were found to significantly influence the yield of the regenerated carbon, while only the regeneration temperature and CO2 flow rate were found to significantly affect the iodine number. The optimized process conditions that maximize the yield and iodine adsorption capacity were identified to be a regeneration temperature of 950 degrees C, time of 120 min and flow rate of CO2 of 600 ml/min, with the corresponding yield and iodine number to be in excess of 50% and 1100 mg/g. The BET surface area of the regenerated composite was estimated to be 1263 m2/g, with micropore to mesopore ratio of 0.75. The pore volume was found to have increased 6 times as compared to the spent catalyst. The composite material (AC/ZnO) with high surface area and pore volume coupled with high yield augur economic feasibility of the process. EDS and XRD spectrum indicate presence of ZnO in the regenerated samples.

Zinc acetate and Zn-oxo complex of Zn4O(CH3COO)6 containing in the spent catalyst of vinyl synthesis were investigated by means of the first principles of density functional (DFT) methods. The geometries, energies, charge populations and local electron density distributions of the two compounds and their formate analogues were analyzed. Based on the pyrolysis characteristics of the spent catalyst, the thermodynamic properties of ΔG, ΔH and ΔS for possible decomposition reactions of zinc acetate and Zn4O(CH3COO)6 were calculated as functions of temperature. The results provide a theoretical evidence that Zn4O(CH3COO)6 is more stable than zinc acetate due to the regular Zn4O and ZnO4 tetrahedral coordination between Zn atoms and two kinds of O atoms. The preparation of Zn4O(CH3COO)6 via the hydrolysis of zinc acetate is thermodynamically feasible. Zn4O(CH3COO)6 is further decomposed into ZnO via a decarboxylation reaction rather than a hydrolysis reaction.

After being subjected to thermal treatment by microwave, a carbon-based spent catalyst from vinyl acetate synthesis has been proved to be a good precursor for the production of ZnO/activated carbon (AC) composites. Different operating activated times were found to have effect on the properties of the composites. As the activated time rises, the surface area of the activated carbon that is acting as the catalyst support increases due to the decomposition of the organic deposits that are clogging the porous structure. XRD was used to evaluate the transformation of zinc acetate to zinc oxide after thermal treatment. Both the iodine adsorption capacity and the yield of the resulting composites were calculated and SEM-EDX analysis was used to evaluate the changes in surface morphology.

ZnO/AC composite was prepared from spent catalyst of vinyl acetate synthesis by using conventional thermal treatment under CO2 atmosphere. The final composite was obtained with the operating conditions of activation temperature of 950°C, activation time of 120min and the CO2 flow rate of 600ml/min. The structure and surface properties of the ZnO/AC composite were observed and characterized by scanning electron microscope (SEM-EDX), X-ray diffraction (XRD), fourier transform infrared spectroscopy (FT-IR) and the UV diffuse reflectance spectra. It was found that the zinc acetate present in the spent catalyst is transformed to zinc oxide (ZnO) after thermal treatment. ZnO particles were well adhered and uniformly distributed onto the carbon surface, forming ZnO/AC composite. The thermal treatment of the spent catalyst gives rise to a material with excellent adsorptive and photocatalytic properties.

The aim of this paper is to study the adsorption characteristics of nitric oxide (NO) and sulfur dioxide (SO2) on raw coal activated carbon over temperature ranged 298～343K using a static volumetric adsorption apparatus. The adsorption equilibrium data for NO and SO2were fitted to Freundlich, Dubinin-Radushkevich (D-R) and Sips adsorption isotherm model. Isosteric heat of adsorption was determined by the Clausius-Clapeyron equation. It was found that Sips adsorption isotherm model is more suitable for description of NO adsorption process at 298K, 313K and 328K and SO2adsorption process at 313K, 328K and 343K, however, D-R adsorption isotherm model is more suitable for description of the NO adsorption process at 343K and SO2adsorption process at 298K. The isosteric heat of adsorption values of SO2increase slightly as the adsorbed amounts increasing from 0.8 to 1.6mg/g, but the isosteric heat of adsorption values of NO show a converse trend. Meanwhile, NO and SO2adsorbed on coal activated carbon at the four temperatures may be a dominant of physical adsorption.

Support vector machines (SVMs) are a promising type of learning machine based on structural risk minimization and statistical learning theory, which can be divided into two categories: support vector classification (SVC) machines and support vector regression machines (SVR). The basic elements and algorithms of SVR machines are discussed. As modeling and prediction methods are introduced into the experiment of microwave preparing partially stabilized zirconia (PSZ) and built the stability prediction model, the better prediction accuracy and the better fitting results are verified and analyzed. This is conducted to elucidate the good generalization performance of SVMs, specially good for dealing with nonlinear data.

A novel solar-powered hybrid energy system with cooling and heating is presented, which consists of an adsorption ice maker subsystem and water heater subsystem. It can be used as an ice maker and water heater hybrid system or a single water heater respectively according to incident solar radiation intensity. A numerical model is developed to predict the performances of the hybrid energy system. Performance simulation and analysis on the hybrid energy system have been made. Simulation results show that, under the climatic conditions of daily solar radiation being about 12-20MJ/m2, the hybrid energy system can be used as an ice maker and a water heater effectively, its daily solar cooling COP (coefficient of performance) is about 0.173 - 0.181, the daily heating coefficient of performance is about 0.294-0.327.

The paper overviewed the recovery methods of germanium, summarized the feature of those methods such as leaching with sulphuric acid, chlorination leaching- distillation, alkali decomposion, leaching with hydrofluoric acid, extracting, reduction and leaching germanium with microorganism. And introduced the principles ,technologies and disadvantages of those methods. Finally, prospected that microwave pretreatment technology and microwave directly leaching can be used in traditional methods such as acid leaching and alkali decomposion to improve the recovery rate of germanium by change insoluable germanium into soluble germanium and upgrade the leaching rate of germanium.

A novel nanofiller containing layered organo-modifed montmorillonite (oM) and mesoporous silica micro-sphere (MS) was prepared by in situ deposition method, and the microstructures and morphologies of this nanofiller were characterized by Fourier transform infrared spectrometry (FTIR) X-ray diffraction (XRD) and transmission electronic microscopy (TEM). EP/oM-MS nanocomposite was obtained by adding oM-MS to EP matrix. Morphologies and mechanical of the new ternary nanocomposite were investigated. For purpose of comparison, the corresponding binary nanocomposites, i.e., EP modified with either oM or MS, were tested as well. The test results of mechanical properties show that oM obviously improves the strength of EP and MS enhances the toughness of EP, but oM-MS exhibits synergistic effect on toughening and reinforcing of EP.

High-porosity silicon nitride ceramics with excellent mechanical properties were fabricated by the carbothermal reduction of SiO2. The influences of sintering conditions on microstructure and mechanical properties were studied. The results showed that microstructure and mechanical properties of porous silicon nitride ceramics were dependent mostly on the sintering conditions. The sintered porous silicon nitride ceramics exhibited the formation of fibrous microstructure with submicrometer-sized, high-aspect ratio b-Si3N4 grains, and uniform pore structure. Porous Si3N4 ceramics with a porosity of about 70%, and a flexural strength of about 70 MPa were obtained by sintering at 1750°C, with lower rate of temperature rise and no retaining time. The high strength was attributed to fine, high-aspect ratio b-Si3N4 grains and uniform pores between grains.

The leaching tests of nickel supported activated carbon under normal pressure in (NH4)2SO4were studied. The effects of experimental condition, such as initial concentration of (NH4)2SO4, liquid-to-solid ratio, leaching time and leaching temperature on the leaching rate of nickel, were investigated. The results show that the leaching rate of nickel is 96.12% with initial concentration of (NH4)2SO4of 7.5%, liquid-to-solid ratio of 2, leaching time of 5h and leaching temperature of 25°C. The morphology of nickel supported activated carbon before and after leaching was characterized by XRD, which proved the effective separation of nickel and activated carbon. The leaching rate of nickel was also shown better at room temperature and atmospheric pressure. Moreover, it needn’t equipments enduring high-pressure and high temperature in the leaching process, thus reducing the costs of leaching equipments greatly. This work provides a new way to the comprehensive utilization of nickel-containing activated carbon.

A microwave carbonthermal nitridation method under the condition of nitrogen at atmospheric pressure was used to the synthesis of vanadium nitride from vanadium pentoxide and carbon black. In the present work, the effects of synthesis temperature, flowing rate of nitrogen, heating rate and soaking time on the apparent density and the nitrogen content of the microwave sintered samples were studied. The experimental data indicated that the apparent density and the nitrogen content of the microwave sinter sample was 4.1 g/cm3 and 13.8 %, respectively under the optimum conditions of flowing rate of nitrogen 50 L/h, heating rate of 6 °C/min to 1400 °C and soaking time of 50 min. The denser pellet was preferred to generated in the centre of the samples of which was beneficial to the expulsion of stoma and the diffusion of nitrogen due to the opposite temperature gradient compared with traditional heating.

This paper reports detailed investigation on the influence of microwave irradiation on the cobalt oxalate (Co(C2O4)·2H2O):cobalt oxide (Co3O4) systems in different mass ratio. The analyses of the spectra attenuation and relative frequency shift showed that Co(C2O4)·2H2O had weak capability to absorb microwave irradiation, while Co3O4 had good capability to absorb microwave irradiation. The ability to absorb microwave irradiation was also assessed based on the temperature raise of the system exposed to microwave irradiation. The capability to absorb microwave irradiation of Co(C2O4)·2H2O increased with an increase of ratio Co3O4 in system.

The stability is a key product performance index, which can directly determine the quality of the partially stabilized zirconia (PSZ), so how to predict the stability of PSZ accurately, quickly and easily in the preparation process is very important. In this paper, a new mathematical model to predict the stability of PSZ prepared by microwave heating was proposed, based on statistical theory (SLT) and support vector machine (SVM) theory, which relates the stability of PSZ and the influence factors, such as the holding temperature, rising rate of temperature, holding time, decreasing rate of temperature and hardening temperature. Typical data collected from 58 experiments were used for the training samples and test samples. Then testing and analyzing was done. The results showed that the SVM model is reasonable and it is accurate and reliable to predict the stability of the partially stabilized zirconia prepared by microwave heating by SVM model. Besides, multiple influence factors can be comprehensively considered in the SVM model, thus a new highly effective method for predicting the stability of PSZ prepared by microwave heating is provided for future application, which is of great significance to theory and practice.