天然钾长石-磷石膏矿化CO_2联产硫酸钾过程评价

利用工业固废磷石膏热活化天然钾长石矿化CO2是一种减排CO2、消除工业固废并联产高价值硫酸钾的新方法。通过耦合热活化钾长石及CO2矿化过程,研究了新工艺的技术条件。通过单因素实验确定了最优化操作条件,并对最优条件下操作过程进行了评价。结果表明,钾长石/硫酸钙质量比1∶2,焙烧温度1 200℃,焙烧时间2 h,矿化温度100℃,初始CO2压力4 MPa为最佳工艺参数,此时提钾率为87%,矿化率为7.7%。新工艺在经济上可行。     

渣油废催化剂回收制备拟薄水铝石

采用渣油废催化剂为原料,考察了焙烧温度,液固比及pH等因素对金属回收率的影响;通过正交实验考察了原料配比、焙烧温度、焙烧时间、液固比及水浸时间对氧化铝转化率的影响,并采用N2物理吸附⁃脱附、XRD和SEM进行表征。结果表明,在焙烧温度800 ℃和液固比为5∶1时,钼和钒的浸出率可以达到94.0%以上;控制pH为1时,钼酸回收率可以达到97.6%;通过正交实验,确定了氧化铝回收条件：原料配比1.5,焙烧温度900 ℃,焙烧时间3 h,液固比5∶1,水浸时间15 min。     

焙烧温度对提纯磷化渣制备LiFePO4/C 正极材料的影响

利用水热酸洗法对固废磷化渣进行提纯,以得到纯度较高的FePO_4·2H_2O为铁源,通过碳热还原法制备LiFePO_4/C正极材料。研究结果表明:当焙烧温度为750?C时,制得的LiFePO_4/C材料晶体结构良好,首次放电比容量为151.9 m A·h/g,首次库伦效率为93.5%;在10 C倍率下容量保持率为65.0%;经过80周循环后,放电比容量基本不衰减,表现出较好的倍率和循环性能。     

膨润土的硫酸铵活化

以硫酸铵为活化剂,通过固相热活化法从膨润土中提取铝,探讨了活化温度、时间和活化剂用量对铝浸出率的影响,并通过XRD和荧光光谱分析对活化后产品的结构和组成进行分析。结果表明,最佳提铝工艺条件为:硫酸铵与膨润土质量比为2.5,在480℃焙烧2 h,铝的浸出率可达到85%。产品的XRD和X荧光光谱分析显示,膨润土的蒙脱石晶体结构得到有效分解,产物主要为活性及晶态的二氧化硅,其纯度达到94.3%。     

膨润土的硫酸铵活化

以硫酸铵为活化剂,通过固相热活化法从膨润土中提取铝,探讨了活化温度、时间和活化剂用量对铝浸出率的影响,并通过XRD和荧光光谱分析对活化后产品的结构和组成进行分析。结果表明,最佳提铝工艺条件为:硫酸铵与膨润土质量比为2.5,在480℃焙烧2 h,铝的浸出率可达到85%。产品的XRD和X荧光光谱分析显示,膨润土的蒙脱石晶体结构得到有效分解,产物主要为活性及晶态的二氧化硅,其纯度达到94.3%。     

白云鄂博铁精矿含碳球团直接还原实验研究

对于白云鄂博铁精矿进行了内配碳直接还原的研究,通过正交实验考察C/O、焙烧温度和H2/CO 3个因素对金属化率的影响.得出最优的实验方案:C/O为1.1,焙烧温度为950℃,H2/CO为3:2.在最优实验方案下,球团金属化率可达89.24%,还原度为91.96%.     

高铝粉煤灰硫酸铵与碳酸钠焙烧活化对比研究

分别采用硫酸铵与碳酸钠焙烧活化法浸出高铝粉煤灰中的铝,考察了焙烧条件(焙烧温度、焙烧时间、试剂添加量)对铝浸出效果的影响,并对焙烧物料和浸出渣的物相进行了分析,探讨了焙烧活化及酸浸提铝的机理.经380℃焙烧,莫来石与硫酸铵活化反应生成易溶于酸的NH4Al(SO4)2,酸浸后,粉煤灰中的铝被成功提取;900℃焙烧下,莫来石及Si O2与碳酸钠活化反应生成易溶于酸的Na Al Si O4,Na2Si O3和Al2O3,酸浸后,粉煤灰中的铝被成功提出,并生成Si O2.两种方法均能实现粉煤灰中铝、硅的分别提取,铝的浸出率超过92%.相较于硫酸铵法,碳酸钠法焙烧温度高,酸浸过程中液固比大,硫酸消耗量高,且易生成凝胶状Si O2而难以过滤分离.因此,硫酸铵焙烧活化-硫酸浸出提取高铝粉煤灰中的铝更具优势.     

全球二氧化碳减排不应是CCS，应是CCU

提出了二氧化碳减排的CCU(Carbon Dioxide Capture and Utilization—CCU)新理念,系统分析了全球现在非常重视和关注的CCS(Carbon Dioxide Capture and Storage—CCS)存在投入较大的经济问题以外还存在比较大的CO2泄露、咸水层破坏、地表拱起和诱发地震等潜在风险。因此作者提出二氧化碳减排不应是CCS而应该是CCU,即在低能耗低成本条件下,利用CO2矿化转化天然矿物和固体废物联产出高附加值的化工产品,将CO2作为一种资源,真正实现CO2的高效利用。作者已探索形成了可行的技术方法,包括氯化镁矿化CO2联产盐酸和碳酸镁、固废磷石膏矿化CO2联产硫基复合肥等技术。研究表明在人类可利用的范围内,利用地壳中1%的钙、镁离子进行CO2矿化利用,理论上以50%的转化率来计算,可矿化约2.56×107亿吨CO2,按照全球2010年的CO2排放量约为300.6亿吨,可满足人类约8.5万年的CO2减排需求。同时中国的磷石膏固废每年产出约5 000万吨,利用其中的钙离子进行CO2矿化,每年可消耗CO2约1 250万吨。作者提出的CO2矿化利用的CCU新理念和技术路线,在实现CO2减排的同时,由于高附加值产品的生成,总体经济效益分析具有较好的利润空间,是真正能够开展规模化工业化应用的二氧化碳减排方法。     

纳米Au／ZnO／TiO2催化剂对富氢气体中CO选择性氧化

以纳米TiO2为载体用共沉淀法负载不同含量Au和ZnO,研究了在不同沉淀剂、焙烧温度和活化条件下制备的催化剂对富氢气体中CO转化率与选择性的影响。反应气采用模拟原料气,用微反-色谱联用装置对反应产物进行催化活性评价,用BET和XRD等方法对合成的催化剂进行表征。实验结果表明催化剂的活性与选择性受沉淀剂、焙烧温度、活化条件等制备因素综合影响。当催化剂组成为Au(2%)ZnO(2%)/TiO2,用尿素做沉淀剂、300℃空气焙烧,氢气条件下还原制备的催化剂在30℃时活性与选择性最佳。     

焙烧改性膨润土处理苯酚废水的效果研究

通过高温焙烧法对辽宁黑山膨润土改性,分析了改性膨润土对苯酚溶液的处理效果。实验使用不同焙烧温度的改性膨润土,探讨了固液比、吸附时间、吸附温度、苯酚浓度等条件对苯酚溶液的吸附效果。结果表明：600℃改性膨润土的吸附效果最佳,苯酚去除率为68.3%;最佳吸附条件为,苯酚浓度为20mg/L、固液比为6g/L、常温吸附时间1.5~2h。     

Use of lime mud from paper mill as a heterogeneous catalyst for transesterification

Lime mud(LM),a solid waste from the paper mill,is used as an economic and environmental friendly heterogeneous basic catalyst for transesterification,which is accompanied by characterization of X-ray fluorescence,thermogravimetric-differential thermal analysis,X-ray diffraction,N2adsorption,and Hammett indicator method.To investigate the performance of the achieved catalyst,which is activated through calcination,the aspects of calcination temperature,reaction time,mole ratio of methanol to oil,catalyst addition percentage,and reaction temperature are concerned.Characterization of catalyst reveals that LM could be activated through calcination to transform the carbonate and hydrate of calcium into the oxide forms and higher calcination temperature could lead to stronger basic strength.However,N2adsorption results indicate that higher temperature causes the sintering of the catalyst and shrinkage of the catalyst grains.When LM is activated at 800°C(LM-800)and the reaction is carried out at 64°C with a methanol to oil mole ratio of 15:1,catalyst addition percentage of 6%,and reaction time of 2h,the maximum transesterification conversion of 94.35%could be achieved.Reusability of LM-800 is also investigated compared with laboratory grade CaO in five reaction cycles and the results indicate that the catalysts derived from LM can be used as an economic and efficient catalyst for biodiesel production.     

Hydrothermal synthesis of xonotlite-type calcium silicate insulation material using industrial zirconium waste residue

Xonotlite-type insulation material was prepared by hydrothermal synthesis technology using industrial zirconium waste residue in this paper,and the phase analysis together with the observation of micro–morphology were also carried out by XRD,SEM and TEM.The density and thermal conductivity were measured finally.The results indicate,chlorine ion impurity contained in zirconium waste residue can be removed effectively via water washed process,and the reactive activity of silicon dioxide is almost not affected,which make it be a good substitution of silicon material for the preparation of calcium silicate insulation material by hydrothermal synthesis technique.The density and thermal conductivity of xonotlite-type calcium silicate insulation material obtained by hydrothermal synthesis technique can reach 159 kg/m3,0.049 W/(m·° C),respectively,meeting with National Standard well,when synthesis conditions are selected as follows:Ca/Si molar ratio equal to 1,synthesis temperature at 210°C and kept for 8 hrs.It provides a new approach to realize lightweight and low thermal conductivity of calcium silicate insulation material.     

Experimental design technique on removal of hydrogen sulfide using CaO-eggshells dispersed onto palm kernel shell activated carbon: Experiment,optimization, equilibrium and kinetic studies

This study presents the use of chicken eggshells waste utilizing palm kernel shell based activated carbon(PKSAC) through the modification of their surface to enhance the adsorption capacity of H_2S. Response surface methodology technique was used to optimize the process conditions and they were found to be: 500 mg/L for H_2S initial concentration, 540 min for contact time and 1 g for adsorbent mass. The impacts of three arrangement factors(calcination temperature of impregnated activated carbon(IAC), the calcium solution concentration and contact time of calcination) on the H_2S removal efficiency and impregnated AC yield were investigated. Both responses IAC yield(IACY, %) and removal efficiency(RE, %) were maximized to optimize the IAC preparation conditions. The optimum preparation conditions for IACY and RE were found as follows: calcination temperature of IAC of 880 ℃, calcium solution concentration of 49.3% and calcination contact time of 57.6 min, which resulted in 35.8% of IACY and 98.2% RE. In addition, the equilibrium and kinetics of the process were investigated. The adsorbent was characterized using TGA, XRD, FTIR, SEM/EDX, and BET. The maximum monolayer adsorption capacity was found to be 543.47 mg/g. The results recommended that the composite of PKSAC and Ca O could be a useful material for H_2S containing wastewater treatment.     

Porous haydite used as waste water filter medium for lake sludge

Porous haydite used as waste filter medium was prepared by dreging lake sludge to help solve the treatment problem of sludge and realize its reclamation. Several calcination regimes were considered and their effects on the pore structure and the properties such as the strength, the density, the filtering ability and the phosphate absorption ability of the haydite were investigated. For the mixture of 60% lake sludge and 40% fly ash in this experiment, the calcination regime with a pre-calcination period at about 600 °C, a temperature keeping period at 1 200 °C and a moderate cooling rate are recommended to prepare haydite with reasonable pore structure and good performances for its usage as the waste water filter media.     

Fe-MnOx催化臭氧氧化甲基橙的研究

实验以甲基橙为目标物,考察Fe-MnOx的催化效果,同时比较不同煅烧温度（300°C、400°C、500°C、600°C和700°C）、Fe/Mn混合比例（Fe/Mn=1/3、Fe/Mn=1/1和Fe/Mn=1/3）等制备条件对催化剂活性的影响,力求得到催化剂的最佳制备条件。结果表明：在400°C,Fe/Mn=1:1的制备条件下,Fe-MnOx催化剂对催化臭氧降解甲基橙表现出显著的催化活性,反应进行20min,甲基橙的去除率高达70.26%,较单独臭氧氧化提高了32.29%;加入叔丁醇后,明显抑制甲基橙去除率,说明催化过程不仅存在羟基自由基反应机理,而且存在臭氧分子与吸附在催化剂表面的甲基橙直接反应的反应途径;为了进一步了解催化剂的催化活性和内部结构之间的内在关系,采用XPS、XRD、TEM和BET等检测技术对催化活性最好的Fe-MnOx催化剂进行表征。表征的结果显示：催化剂中存在Fe2O3、FeO(OH)、 MnO2和Mn5O8,且催化剂结构呈不定晶型,结构疏散,表面孔隙多,比表面积高达117.81 m2/g。     

Comparison of temperature field distribution between cement preclinkering technology and cement precalcining technology

Through the comparison of calcination conditions between cement preclinkering technology and cement precalcining technology,we studied the characteristics of temperature field distribution of cement preclinkering technology systems including cyclone preheater,preclinkering furnace,and rotary kiln.We used numericalsimulation method to obtain data of temperature field distribution.Some results are found by system study.The ratio of tailcoalof cement preclinkering technology is about 70%,and raw mealtemperature can reach 1070 ℃.Shorter L/D kiln type of preclinkering technology can obtain more stable calcining zone temperature.The highest solid temperature of cement preclinkering technology is higher than 80 ℃,and high temperature region(1450 ℃)length is 2 times,which is beneficialfor calcining clinker and higher clinker quality.So cement preclinkering technology can obtain more performance temperature filed,which improves both the solid-phase reaction and liquid-phase reaction.     

Structure transition of nano-titania during calcination

1　INTRODUCTIONTitaniahasthreecrystallines :brookite ,anataseandrutile .Theirbasicstructuralunitisthesame[TiO6 ]octahedron ,buttheirlatticestructuresaredifferent .Forexample ,brookitebelongstorhombiccrystallo series ,whilerutileandanatasebelongtosquarecrystallo series .Thoughrutileandanatasearethesamecrystallo series ,theirsymmetricalelementsandunit cellparametersaredifferent[1] .Inrecentyears ,muchattentionhasbeenpaidtophasetransformationoftitaniaparticle ,especiallytothetemperatureofph…     

Generation of electricity from CO_2 mineralization: Principle and realization

Current CO2 reduction and utilization technologies suffer from high energy consuming. Thus, an energy favourable route is in urgent demanding. CO2 mineralization is theoretically an energy releasing process for CO2 reduction and utilization, but an approach to recovery this energy has so far remained elusive. For the first time, here we proposed the principle of harvesting electrical energy directly from CO2 mineralization, and realized an energy output strategy for CO2 utilization and reduction via a CO2-mineralization fuel cell(CMFC) system. In this system CO2 and industrial alkaline wastes were used as feedstock, and industrial valuable Na HCO3 was produced concomitantly during the electricity generation. The highest power density of this system reached 5.5 W/m2, higher than many microbial fuel cells. The maximum open circuit voltage reached 0.452 V. Moreover, this system was demonstrated viable to low concentration CO2(10%) and other carbonation process. Thus, the existing of an energy-generating and environmentally friendly strategy to utilize CO2 as a supplement to the current scenario of CO2 emission control has been demonstrated.     

钙基吸收剂CCCR法脱除CO_2的固定床过程实验研究

为了系统研究煅烧气氛中CO2分压力、煅烧温度、水蒸汽及循环次数对碳酸化转化率X的综合影响,探究在不同工况下使转化率衰减的主导因素,通过自建固定床反应实验台,在多工况下进行了实验研究,并用氮吸附法测量吸收剂煅烧产物微观结构进行分析。结果表明:850℃以上随煅烧温度的提高,碳酸化转化率X逐渐下降,高CO2气氛下,此下降趋势将被减缓;煅烧温度接近窗口温度时,烧结作用为X下降主导因素,CO2则影响不大;多次循环过程中,高CO2分压气氛下,CO2作为烧结媒介,在转化率下降过程中起主要作用,煅烧温度影响不大;煅烧气氛中水蒸汽的存在可在一定程度上使碳酸化转化率提高。     

New activated carbon with high thermal conductivity and its microwave regeneration performance

Using a walnut shellas a carbon source and ZnCl_2 as an activating agent,we resolved the temperature gradient problems of activated carbon in the microwave desorption process.An appropriate amount of silicon carbide was added to prepare the composite activated carbon with high thermalconductivity while developing VOC adsorption-microwave regeneration technology.The experimentalresults show that the coefficient of thermalconductivity of SiC-AC is three times as much as those of AC and SY-6.When microwave power was 480 W in its microwave desorption,the temperature of the bed thermaldesorption was 10 ℃ to 30 ℃ below that of normalactivated carbon prepared in our laboratory.The toluene desorption activation energy was 16.05 k J·mol~(-1),which was 15% less than the desorption activation energy of commercialactivated carbon.This study testified that the process could maintain its high adsorption and regeneration desorption performances.