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1.
传统水泥工业不可持续发展的因素与中国水泥工业可持续发展的对策 总被引:3,自引:0,他引:3
如何及早认识,采取有力措施,发扬水泥工业有利的一面,克服水泥工业不利的一面,为人类的可持续发展服务,为人类造福,这是世界可持续发展工商理事会(WBCSD)和中国企业联合会(CEC)联合举办“面向可持续发展的水泥工业专题研讨会”的主题,在资源、能源、环境等三个方面存在着制约传统水泥工业不可持续发展的因素,提出了实现水泥工业可持续发展的7点对策。 相似文献
2.
The pulse corona plasma has been used as an activation method for reaction of methane and carbon dioxide, the product was C2 hydrocarbons and by-products were CO and H2. Methane conversion and the yield of C2 hydrocarbons were affected by the carbon dioxide concentration in the feed. The conversion of methane increased with increasing carbon dioxide concentration in the feed whereas the yield of C2 hydrocarbons decreased. The synergism of La2O3/γ-Al2O3 and plasma gave methane conversion of 24.9% and C2 hydrocarbons yield of 18.1% were obtained at the power input of plasma was 30 W. The distribution of C2 hydrocarbons changed by using Pd-La2O3/γ-Al2O3 catalyst, the major C2 product was ethylene. 相似文献
3.
Consumption of fossil fuel resources throughout the industrial era has resulted in an enormous increase in carbon dioxide concentration in the atmosphere. Developed countries have committed to reducing the atmospheric load of greenhouse gases and ratified the Kyoto Protocol. Chemical utilization of carbon dioxide captured from large scale stationary sources is one possible pathway to decrease the rate of emissions. Catalysis plays a crucial role in these carbon dioxide utilization reactions. In this paper, the production of synthesis gas from carbon dioxide-containing secondary gases and carbon dioxide hydrogenation to methanol over copper-based zirconia-containing catalysts have been investigated. Pathways of carbon dioxide utilization are outlined, research done on carbon dioxide hydrogenation over copper-based zirconia-containing catalysts is reviewed, and the challenges of these reactions are reported. It is argued that direct utilization of secondary carbon dioxide from industrial sources can be a significant step toward developing sustainable industrial practices and a critical part in sustainable energy strategies. 相似文献
4.
The effects of carbon dioxide on the dehydrogenation of C3H8 to produce C3H6 were investigated over several Cr2O3 catalysts supported on Al2O3, active carbon and SiO2. Carbon dioxide exerted promoting effects only on SiO2-supported Cr2O3 catalysts. The promoting effects of carbon dioxide over a Cr2O3/SiO2 catalyst were to enhance the yield of C3H6 and to suppress the catalyst deactivation. 相似文献
5.
Laura A. Pellegrini Stefania Moioli Simone Gamba 《Chemical Engineering Research and Design》2011,89(9):1676-1683
The most commonly used process for the CO2 capture is absorption by means of chemical solvents such as alkanolamines. This consolidated technology can be applied to CO2 removal from natural gas, refinery gas, and exhaust gas of power plants.This paper focuses on CO2 capture from exhaust gas by absorption with monoethanolamine (MEA).A commercial simulation software, namely Aspen Plus®, is used, with Electrolyte-NRTL thermodynamic package where ad hoc parameters, obtained from regression of experimental solubility data for the system CO2-MEA-H2O, have been implemented.The comparison among different schemes is based on energy saving. Both the reboiler heat duty and the total equivalent work (which sums up every work and heat contribution in the purification section) are considered as criteria for comparison. 相似文献
6.
Benjaram M. Reddy Seung-Cheol Lee Dae-Soo Han Sang-Eon Park 《Applied catalysis. B, Environmental》2009,87(3-4):230-238
Vanadium oxide and cerium oxide doped titania–zirconia mixed oxides were explored for oxidative dehydrogenation of ethylbenzene to styrene utilizing carbon dioxide as a soft oxidant. The investigated TiO2–ZrO2 mixed oxide support with high specific surface area (207 m2 g−1) was synthesized by a coprecipitation method. Over the calcined support (550 °C), a monolayer equivalent (15 wt.%) of V2O5, CeO2 or a combination of both were deposited by using wet-impregnation or co-impregnation methods to make the V2O5/TiO2–ZrO2, CeO2/TiO2–ZrO2 and V2O5–CeO2/TiO2–ZrO2 combination catalysts, respectively. These catalysts were characterized using X-ray diffraction (XRD), Raman, scanning electron microscopy (SEM), transmission electron microscopy (TEM), temperature preprogrammed reduction (TPR), CO2 temperature preprogrammed desorption (TPD) and BET surface area methods. All characterization studies revealed that the deposited promoter oxides are in a highly dispersed form over the support, and the combined acid–base and redox properties of the catalysts play a major role in this reaction. The V2O5–CeO2/TiO2–ZrO2 catalyst exhibited a better conversion and product selectivity than other combinations. In particular, the addition of CeO2 to V2O5/TiO2–ZrO2 prevented catalyst deactivation and helped to maintain a high and stable catalytic activity. 相似文献
7.
The relationship between the catalytic activity of carbided molybdena–alumina and the methane desorption from carbidic carbon through temperature-programmed surface reaction (TPSR) were studied. The effects of passivation and hydrogen treatment on the catalytic activities of molybdenum carbides for CO2 hydrogenation were determined. When the 973 K-carbided catalyst was reduced at 773 K with hydrogen, the catalyst exhibited the highest activity for the reaction, the activity decreasing with increasing H2 pretreatment temperature. Passivation of this catalyst decreased the reaction rate by 20%. TPSR results were correlated with the activity to reveal that molybdenum carbide with slightly deficient carbidic carbon (Mo2C0.962C1.0) serves as an active site for CO2 hydrogenation. 相似文献
8.
Hisanori Ando Qiang Xu Masahiro Fujiwara Yasuyuki Matsumura Mutsuo Tanaka Yoshie Souma 《Catalysis Today》1998,45(1-4):229-234
Hydrocarbons and carbon monoxide were produced from carbon dioxide and hydrogen at 400°C over copper-promoted iron catalysts containing sodium. The major surface phases of the catalysts were FeO and/or FeCO3 although iron carbide is believed as an active phase of the hydrocarbon synthesis from carbon monoxide. Copper was present as metal on the surface and the surface density was considerably high even if the content of copper was less than 1 wt%. The surface density of sodium was not negligible in the catalysts containing sodium less than 0.1 wt% and the sodium ion can affect the surface basicity of the catalysts. The olefin content in the products is believed to relate to the surface basicity. 相似文献
9.
地球上资源有限,而二氧化碳资源十分丰富,二氧化碳在大气中的增加会产生温室效应,开发利用二氧化碳,大力发展二氧化碳产业,具有很大的资源利用和环保意义。本文对近期二氧化碳开发利用的进展作了介绍,并对如何发展二氧化碳产业提出了建议。 相似文献
10.
Mesoporous Ni-CaO-ZrO2 nanocomposites with high thermal stability were designed and employed in the CO2/CH4 reforming. The nanocomposites with appropriate Ni/Ca/Zr molar ratios exhibited excellent activity and prominent coking resistivity. The Ni crystallites were effectively controlled under the critical size for coke formation in such nanocomposites. It was found that low Ni content resulted in high metal dispersion and good catalytic performance. Moreover, the basicity of the matrices improved the chemisorption of CO2 and promoted the gasification of deposited coke on the catalyst. 相似文献
11.
Past research with high temperature molten carbonate electrochemical cells has shown that carbon dioxide can be separated from flue gas streams produced by pulverized coal combustion for power generation. However, the presence of trace contaminants, i.e., sulfur dioxide and nitric oxides, will impact the electrolyte within the cell. If a lower temperature cell could be devised that would utilize the benefits of commercially-available, upstream desulfurization and denitrification in the power plant, then this CO2 separation technique can approach more viability in the carbon sequestration area. Recent work has led to the assembly and successful operation of a low temperature electrochemical cell. In the proof-of-concept testing with this cell, an anion exchange membrane was sandwiched between gas-diffusion electrodes consisting of nickel-based anode electrocatalysts on carbon paper. When a potential was applied across the cell and a mixture of oxygen and carbon dioxide was flowed over the wetted electrolyte on the cathode side, a stream of CO2 to O2 was produced on the anode side, suggesting that carbonate/bicarbonate ions are the CO2 carrier in the membrane. Since a mixture of CO2 and O2 is produced, the possibility exists to use this stream in oxy-firing of additional fuel.From this research, a novel concept for efficiently producing a carbon dioxide rich effluent from combustion of a fossil fuel was proposed. Carbon dioxide and oxygen are captured from the flue gas of a fossil-fuel combustor by one or more electrochemical cells or cell stacks. The separated stream is then transferred to an oxy-fired combustor which uses the gas stream for ancillary combustion, ultimately resulting in an effluent rich in carbon dioxide. A portion of the resulting flow produced by the oxy-fired combustor may be continuously recycled back into the oxy-fired combustor for temperature control and an optimal carbon dioxide rich effluent. 相似文献
12.
M. Rezaei S.M. Alavi S. Sahebdelfar Peng Bai Xinmei Liu Zi-Feng Yan 《Applied catalysis. B, Environmental》2008,77(3-4):346-354
Mesoporous nanocrystalline zirconia with high-surface area and pure tetragonal crystalline phase has been prepared by the surfactant-assisted route, using Pluronic P123 block copolymer surfactant. The synthesized zirconia showed a surface area of 174 m2 g−1 after calcination at 700 °C for 4 h. The prepared zirconia was employed as a support for nickel catalysts in dry reforming reaction. It was found that these catalysts possessed a mesoporous structure and even high-surface area. The activity results indicated that the nickel catalyst showed stable activity for syngas production with a decrease of about 4% in methane conversion after 50 h of reaction. Addition of promoters (CeO2, La2O3 and K2O) to the catalyst improved both the activity and stability of the nickel catalyst, without any decrease in methane conversion after 50 h of reaction. 相似文献
13.
The paper takes into consideration a new approach for CO2 capture and transport, based on the formation of solid CO2 hydrates.Carbon dioxide sequestration from power plants can take advantage of the properties of gas hydrates. The formation and decomposition of hydrates from various N2-CO2 mixtures has been studied experimentally in a 2 l reactor, to determine the CO2 separation in terms of hydrate composition and residual CO2 content in the reacted gas.Carbon dioxide acts as a co-former for the production of hydrates containing nitrogen, besides CO2. The mixed hydrates that are obtained are less stable than simple CO2 hydrates. When CO2 content in the flue gas is higher than 30% by volume, the hydrates formed at 5 MPa are sufficiently concentrated (about 70% CO2) and carbon dioxide reduction in the reacted gas is acceptable.The application of a process based on hydrate formation could be especially interesting (for CO2 capture and transport) when connected to an oxy-coal combustion process; in this case the CO2 content in the flue gas is very high and the hydrate formation is greatly facilitated. 相似文献
14.
15.
Dispersion polymerization of styrene has been performed in CO2-expanded ethanol at ≤9 MPa and 70 °C using PVP as stabilizer. The polymerizations proceeded with good colloidal stability, resulting in spherical particles of diameters of ∼2 μm. Pressurization with CO2 leads to an increase in particle size (∼1 μm in the corresponding CO2-free system), and a decrease in both polymerization rate and molecular weight. The main effect of CO2 is proposed to be its influence on the partitioning of monomer between the continuous and the particle phase–the results indicate that CO2-pressurization causes a reduction in monomer concentration in the particles. Overall, the results are consistent with literature data on the effects of the polarity of the continuous phase in dispersion polymerization of styrene in alcohols and alcohol/water mixtures. 相似文献
16.
The aim of this study is the characterisation of VLE and chemical equilibria for the system CO2/diethanolamine (DEA)/H2O/methanol. The effect of MeOH composition has been studied using four compositions (from 0 to 30 wt% of methanol with a fixed composition (30 wt%) of DEA), the measurement being made at T = 298.15 K and at various CO2 loadings (from 0.2 to 0.8). An original experimental device was used. This device combines a FT-IR spectroscopy analysis of the liquid phase with a VLE measurement cell.The data base obtained, including the new solubility data and the liquid phase composition, allows the modelling of the system CO2/DEA/H2O/methanol using an electrolyte equation of state [Fürst, W., Renon, H., 1993, Representation of excess properties of electrolyte solutions using a new equation of state, AIChE J, 39(2): 335–343] representing the equilibrium properties of the system and the liquid phase speciation. 相似文献
17.
Aiyu Yan Vasiliki Maragou Antonino Arico Mojie Cheng Panagiotis Tsiakaras 《Applied catalysis. B, Environmental》2007,76(3-4):320-327
The effect of carbon dioxide on the chemical stability of a Ba0.5Sr0.5Co0.8Fe0.2O3−δ cathode in the real reaction environment at 450 °C was investigated by X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), temperature programmed desorption (TPD), X-ray diffraction (XRD) and electrochemical impedance spectra (EIS) techniques. It was found that the presence even of very small quantities of CO2 seriously deteriorates the fuel cell performance at 450 °C. XPS, TPD and XRD results strongly evidenced the formation of carbonates involving strontium and possibly barium after the BSCF cathode was operated in 1% CO2/O2 gas mixture at 450 °C for 24 h. SEM-EDX analysis of the BSCF cathode surface, after treatment in CO2/O2 environment at 450 °C, showed small particles on the surface probably associated with a carbonate phase and a segregated phase of the perovskite. The corresponding EDX spectra confirmed the presence of a carbonate layer and also revealed the surface enrichment of strontium and barium elements. EIS results indicated that both ohmic and polarization resistances increased gradually with the introduction of carbon dioxide in the oxidant stream, which could be interpreted by the decreased oxygen reduction kinetics and the formation of carbonate insulating layer. 相似文献
18.
In this work, we report the development of MnO2/F-MWCNT/Ta hybrid nanocomposite sensor with different MnO2 overlayer thickness for the detection of H2O2 in real samples. A novel two-step process using e-beam evaporation and spray pyrolysis deposition was adopted for the synthesis of hybrid MnO2/F-MWCNT/Ta electrodes. SE morphology revealed smaller-sized, compact grains of MnO2 infiltrated on the outermost walls of MWCNTs. Raman analysis confirmed the existence of carbon nanotubes with abundant structural defects of MnO2 in the composite. The cyclic voltammetry results displayed a high peak current and narrowed over potential towards the reduction of H2O2. The sensor displayed a fast response (<5?s), wide linear range (2–1510?μM) and a low limit of detection (0.04?μM) with significant anti-interfering properties, promising for the development of highly sensitive and reproducible biosensors. The three dimensional nanocomposite sensor also exhibited good recovery (> 98%), thus providing a favourable tool for analysis of H2O2 in milk samples. 相似文献
19.
The influence of different metal oxide supports (i.e. ZrO2, ThO2, UO2, TiO2 and SiO2) on the performance of Ni- and/or Co-containing catalysts [Ni and/or Co/MO2 mole ratio (where M=Zr, Th, U, Ti or Si)=1.0] in the oxidative methane-to-syngas conversion at very low contact time (GHSV=5.2×105 cm3 g−1 h−1 at STP) was investigated. The nickel-containing ZrO2, ThO2 and UO2 catalysts (with or without pre-reduction by hydrogen at 500°C) showed good performance in the process; the order of their performance is NiO–ThO2>NiO–UO2>NiO–ZrO2. The NiO–TiO2 showed appreciable catalytic activity only after its reduction at 800°C. However, this catalyst and the NiO–SiO2 catalyst showed poor performance in the process. These two catalysts are also deactivated very fast, mostly because of sintering of Ni and/or formation of catalytically inactive binary metal oxide phases by solid–solid reaction at the high catalyst calcination and/or catalytic reaction temperature. Although the Ni-containing ThO2, UO2 and ZrO2 catalysts showed good performance, carbon deposition on them during the process is fast. However, because of the addition of cobalt to these catalysts (with Co/Ni=1.0), the rate of carbon deposition on them in the process is drastically reduced. This Co addition however resulted in a significant decrease in both the conversion and selectivity; the decrease in the selectivity was small. 相似文献
20.
Michael J. Bortner 《Polymer》2004,45(10):3399-3412
Acrylonitrile (AN) copolymers (AN content greater than about 85 mol%) are traditionally solution processed to avoid a cyclization and crosslinking reaction that takes place at temperatures where melt processing would be feasible. It is well known that carbon dioxide (CO2) reduces the glass transition temperature (Tg) and consequently the viscosity of many glassy and some semi-crystalline thermoplastics. However, the ability of CO2 to act as a processing aid and permit processing of thermally unstable polymers at temperatures below the onset of thermal degradation has not been explored. This study concentrates on the ability to plasticize an AN copolymer with CO2, which may ultimately permit melt processing at reduced temperatures. To facilitate viscosity measurements and maximize the CO2 absorption, a relatively thermally stable, commercially produced AN copolymer containing 65 mol% AN was investigated in this research. Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) indicated that CO2 significantly absorbs into and reduces the Tg of the AN copolymer. Pressurized capillary rheometry indicated that the magnitude of the viscosity reduction is dependent on the amount of absorbed CO2, which correlates directly to the Tg reduction of the plasticized material. Up to a 60% viscosity reduction was obtained over the range of shear rates tested for the plasticized copolymer containing up to 6.7 wt% CO2 (31 °C Tg reduction), corresponding to as much as a 30 °C equivalent reduction in processing temperature. A Williams-Landel-Ferry (WLF) analysis was used to estimate the viscosity reduction based on the Tg reduction (and corresponding amount of absorbed CO2) in the plasticized AN copolymer, and the predicted viscosity reduction based on using the universal constants was 34-85% higher than measured, depending on the amount of absorbed CO2. Van Krevelen's empirical solubility relationships were used to calculate the expected absorbance levels of CO2, and found to be highly dependent on the choice of constants within the statistical ranges of error of the Van Krevelen relationships. 相似文献