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1.
采用气液硫化法对模拟含锌污酸废水进行处理,考察pH值、H2S气体分压、反应温度、反应时间、Zn~(2+)初始浓度等条件对Zn~(2+)去除效果的影响。在单因素实验的基础上进行五因素五水平的正交实验,并对采用该工艺处理冶炼烟气洗涤污酸废水效果进行验证。研究Zn~(2+)硫化分离的热力学,及其气液反应动力学过程,并对锌沉渣进行分析与表征。结果表明:在最佳工艺条件为模拟溶液初始pH值3、反应时间80 min、温度35℃、H2S气体的体积分数为30%、Zn~(2+)初始浓度100 mg/L时,Zn~(2+)脱除率为99.54%,沉渣主要物相为ZnS,锌的质量分数达63.84%;实际污酸废水锌浓度为569和216.7 mg/L时,去除率分别达到99.79%和99.49%。  相似文献   

2.
以液相还原法制备纳米零价铁,将其负载于石墨表面制备负载型纳米零价铁复合材料(G-nZVI),并用来去除溶液中的U(Ⅵ),考察初始溶液的pH、反应温度、反应时间、U(Ⅵ)的初始浓度以及固液比等因素对复合材料(G-nZVI)去除U(Ⅵ)影响。用扫描电镜(SEM)和X射线衍射(XRD)技术对反应前后的材料进行表征,分析其去除U(Ⅵ)的机理。结果表明:纳米零价铁颗粒分散在石墨粉的表面,没有产生团聚。反应后溶液中主要生成UO_2和U(Ⅳ)氢氧化物沉淀。石墨负载型纳米零价铁对U(Ⅵ)有很好的去除效果,在pH为4.0,温度为30℃,反应时间为60 min,固液比为0.25 g/L,初始U(Ⅵ)浓度为10 mg/L条件下,U(Ⅵ)的去除率和吸附容量分别达到99.67%和43.2 mg/g,说明该复合材料(G-nZVI)在含铀放射性废水的处理与环境修复中具有潜在的应用价值。  相似文献   

3.
以聚合氯化铝(PAC)生产过程中铝钙粉浸出渣为原料,通过酸浸-焙烧-水热晶化工艺制备沸石,并研究其对锌冶炼废水中重金属的去除效果。结果表明:铝钙粉浸出渣通过酸浸-焙烧-水热晶化过程,当原料n(SiO_2)/n(Al_2O_3)=2时,产物物相为结构完整的A型沸石;当原料n(SiO_2)/n(Al_2O_3)=6时,产物物相为结构完整的P型沸石。拟二级动力学方程计算得到A型沸石对Zn~(2+)、Cd~(2+)的平衡吸附量分别为97.09、12.39 mg/g,P型沸石对Zn~(2+)、Cd~(2+)的平衡吸附量分别为57.84、10.82mg/g。Freundlich吸附等温线拟合结果表明,A型沸石和P型沸石吸附Zn~(2+)、Cd~(2+)机理均为非均相表面的复杂吸附。当废水pH为8、吸附温度为25℃、吸附时间为150 min时,采用A型沸石处理锌冶炼废水,产渣量为1.1 g/L,废水中Cu~(2+)、Pb~(2+)、Zn~(2+)、Cd~(2+)、总砷(AsT)浓度分别由1.68、13.12、147.00、15.14、4.06 mg/L降至0.06、0.05、0.52、0.03、0.01 mg/L,达到《铅、锌污染物排放标准》(GB25466—2010)。  相似文献   

4.
以非活性羊栖菜粉为吸附剂,研究羊栖菜对水溶液中Cd~(2+)的吸附特性。结果发现:在最佳吸附pH为5,温度为313.15K,吸附剂浓度为1g/L,Cd~(2+)初始浓度为40mg/L左右时,羊栖菜对镉离子的去除率的最大值为92.54%,且吸附10 min时,即达到最大去除率93.95%;在60 min时,基本达到吸附平衡,羊栖菜对Cd~(2+)的去除具有快速、去除率高的特点。动力学实验数据符合准二级动力学模型,Langmuir对热力学实验平衡数据的拟合较高,最大理论吸附容量为68.49 mg/g。通过方程拟合和SEM分析发现吸附过程发生了离子交换。FTIR分析显示,羟基、羧基等官能团在吸附过程中发挥了作用,通过解吸可以实现羊栖菜粉的再生和循环利用。  相似文献   

5.
通过气-液硫化反应初步分离污酸废水中的铜和砷,并将一级铜、砷分离渣按一定比例加入污酸原液中实现溶液中铜和渣中砷的置换分离。考察反应时间、温度和H2S用量对铜、砷去除率的影响,同时考察固液比、时间和温度对铜、砷置换反应的影响。当在50℃时加入20mmol/L的H2S时,在0.5min时间内即可使铜的去除率达到80%以上,且砷的去除率约为20%。将铜、砷一级分离渣按照10%以上的固液比例加入污酸废水中,在20℃下10min后由于铜、砷置换作用,废酸中铜和砷分离率达到99%以上。沉渣中主要物相为CuS,富集的铜渣中铜的质量分数为63.38%。  相似文献   

6.
《轻金属》2015,(6)
本文以高铝粉煤灰提铝过程中产生的副产物活性硅酸钙为吸附剂,研究了活性硅酸钙添加量、吸附温度及吸附时间对活性硅酸钙吸附铝酸钠粗液中铁化合物效果的影响。试验结果表明:活性硅酸钙加入量为10g/L、吸附温度70℃、吸附时间60min的条件下,铝酸钠粗液中Fe2O3质量浓度由8.6mg/L降低至2.53mg/L,除铁率达70.59%。吸附过程对铝酸钠粗液成分及活性硅酸钙固相组成影响很小;吸附过程更符合Freundlich方程,其吸附机制为化学吸附。  相似文献   

7.
生物法制备聚合硫酸铁及其应用研究   总被引:2,自引:0,他引:2  
研究生物法制备铁系絮凝剂及其影响因素。以FeSO4·7H2O为原料,利用驯化后的氧化亚铁硫杆菌(T·f)在酸性条件下的催化氧化作用制备生物聚合硫酸铁(PFS),并确定最佳制备条件。实验表明:在反应液初始pH值1.5、硫酸铵用量0.5g/L、初始Fe2+浓度45g/L、接种量10%、温度30℃时,在转速为120r/min的恒温水浴摇床中连续培养5~6d、可以制出pH1.5~2.2、盐基度17.5%~22.7%、全铁含量43.87~45.24g/L的产品。实验通过处理3种废水来考察其絮凝性能,结果表明:当PFS投加量一定时,COD去除率可达70%以上,脱色率达90%,Zn2+去除率达99%,说明PFS是一种絮凝效果优异的水处理剂。  相似文献   

8.
为了在中国南方有色矿冶区同时实现工业钨渣的资源化利用和重金属废水的处理,以钨渣和硅藻土为主要原料制备一种新型陶粒,对其与溶液中重金属Cu~(2+)的吸附规律进行研究。结果表明:新制备的近球形陶粒表面粗糙多孔,内部有许多贯穿性孔道与外部相连通;陶粒的主要物相组成含有MnFe_2O_4。在303 K、铜离子初始浓度100 mg/L、陶粒投加量0.5 g和300 min条件下,陶粒对Cu~(2+)的吸附量为9.421 mg/g,吸附去除率达94.21%。随着陶粒投加量的增大,其对溶液中Cu~(2+)的总吸附量增大,单位吸附量降低;陶粒对Cu~(2+)的吸附量随试验pH值的增大而增大。陶粒对Cu~(2+)的等温吸附更符合Freundlich模型,吸附主要发生在非均质表面,为优惠吸附;陶粒对铜离子的吸附动力学符合准二级动力学方程,吸附过程主要受液膜扩散、表面吸附以及颗粒内扩散因素控制。对于实际重金属废水的处理,陶粒对重金属离子的吸附初始阶段受扩散控制,此时,可通过加强搅拌的方式提高Cu~(2+)的去除率。  相似文献   

9.
离子交换吸附富集红土镍矿浸出液中的镍   总被引:1,自引:0,他引:1  
研究高镁铁质红土镍矿硫酸浸出液中镍的高效提取方法。通过在d 150 mm×1800 mm PVC柱中填充12 L CN27离子交换树脂,对高镁铁质红土镍矿硫酸浸出液进行动态吸附。研究初始液pH、Ni2+和Fe2+的质量浓度、流速、吸附时间等参数对树脂有效吸附量和吸附效率的影响。结果表明:初始液中Ni2+质量浓度2.5 g/L、pH 3~5、流速1.0 L/min、树脂饱和吸附时的有效利用率达85%~93%,树脂吸附Ni2+的最高有效吸附量可达58.0 g/kg;初始液中Ni2+质量浓度2.5 g/L、pH 4.5、流速1.0 L/min时,吸附后液Ni2+质量浓度1.0 mg/L时,树脂吸附Ni2+的有效吸附量可达41.8~42.0 g/kg,富集液中Ni2+的富集倍数达到25以上,镍离子的质量浓度提高到54 g/L以上;初始液中Fe2+的质量浓度增加,树脂对镍的吸附量降低,不仅会导致富集液中Ni2+的质量浓度降低,富集液中Fe2+的质量浓度也会增加。离子交换吸附不但能使低浓度含镍溶液富集到满足镍电积工艺的要求,且能对杂质进行有效分离。  相似文献   

10.
为有效去除锌湿法冶金过程中的微量钴,探索采用臭氧氧化净化ZnSO4溶液中钴的可行性,考察搅拌速度、反应温度、气体流量、溶液pH值、钴离子浓度、锌离子浓度等因素对除钴效果的影响。结果表明:在锌离子初始浓度100 g/L、钴离子初始浓度20 mg/L、温度30℃、气体流量800 mL/min、pH=5.0、搅拌速度800 r/min等条件下,反应30 min后,钴浓度可降至0.2 mg/L,除钴率高达99%。  相似文献   

11.
In as-welded state, each region of 2219 aluminum alloy TIG-welded joint shows diff erent microstructure and microhardness due to the diff erent welding heat cycles and the resulting evolution of second phases. After the post-weld heat treatment, both the amount and the size of the eutectic structure or θ phases decreased. Correspondingly, both the Cu content in α-Al matrix and the microhardness increased to a similar level in each region of the joint, and the tensile strength of the entire joint was greatly improved. Post-weld heat treatment played the role of solid solution strengthening and aging strengthening. After the post-weld heat treatment, the weld performance became similar to other regions, but weld reinforcements lost their reinforcing eff ect on the weld and their existence was more of an adverse eff ect. The joint without weld reinforcements after the post-weld heat treatment had the optimal tensile properties, and the specimens randomly crack in the weld zone.  相似文献   

12.
After nearly two years' tense construction, the first phase of industrialized base of Shenyang Research Institute of Foundry (SRIF), located at the Tiexi Casting and Forging Industrial Park in the west of Tiexi District, has now been completed and formally put into operation.  相似文献   

13.
The motion of melt droplets in spray degassing process was analyzed theoretically. The height of the treatment tank in spray degassing process could be determined by the results of theoretical calculation of motion of melt droplets. To know whether the melt droplets would solidify during spraying process, the balance temperature of melt droplets was also theoretically analyzed. Then proof experiments for theoretical results about temperature of melt droplets were carried. In comparison, the experimental results were nearly similar to the calculation results.  相似文献   

14.
On the basis of the single-particle framework, a new theory on inclusion growth in metallurgical melts is developed to study the kinetics of inclusion growth on account of reaction and collision. The studies show that the early growth of inclusion depends on reaction growth and Brawnian motion collision, and where the former is decisive, the late growth depends on turbulence collision and Stokes' collision, and where the former is dominant; collision growth is very quick during the smelting process, lessened in the refining process, but nearly negligible in the continuous casting process.  相似文献   

15.
An approach based on film buckling under simple uniaxial tensile testing was utilized in this paper to quantitatively estimate the interfacial energy of the nanostructured multilayer films(NMFs) adherent to flexible substrates. The interfacial energies of polyimide-supported NMFs are determined to be *5.0 J/m2 for Cu/Cr, *4.1 J/m2 for Cu/Ta,*2.8 J/m2 for Cu/Mo, *1.1 J/m2 for Cu/Nb, and *1.2 J/m2 for Cu/Zr NMFs. Furthermore, a linear relationship between the adhesion energy and the interfacial shear strength is clearly demonstrated for the Cu-based NMFs, which is highly indicative of the applicability and reliability of the modified models.  相似文献   

16.
A 17 vol% SiCp/Al–Mg–Si–Cu composite plate with a thickness of 3 mm was successfully friction stir welded(FSWed) at a very high welding speed of 2000 mm/min for the first time. Microstructural observation indicated that the coarsening of the precipitates was greatly inhibited in the heat-affected zone of the FSW joint at high welding speed, due to the significantly reduced peak temperature and duration at high temperature. Therefore, prominent enhancement of the hardness was achieved at the lowest hardness zone of the FSW joint at this high welding speed, which was similar to that of the nugget zone. Furthermore, the ultimate tensile strength of the joint was as high as 369 MPa, which was much higher than that obtained at low welding speed of 100 mm/min(298 MPa). This study provides an effective method to weld aluminum matrix composite with superior quality and high welding efficiency.  相似文献   

17.
吴玉梅  熊晓云  靳蓉  孙敬民  杨林  罗晓星 《金属学报》2005,10(10):1100-1103
目的: 观察本实验室合成的一种治疗阿尔茨海默氏症(AD)的药物(1-二甲基磷酰基-2, 2, 2 -三氯)-乙基-1-醇烟酸醋(NMF),对体外培养的皮层神经细胞活性的影响以及对海人藻酸(KA)所致的神经损伤的保护作用。方法: 采用体外培养皮层神经元的方法,解剖分离 15 d胚胎小鼠皮层神经细胞, 接种于 96孔板,48 h 后加药并培养 72 h,以 MIT 法 观察 NMF 对小鼠皮层神经细胞活性的影响;同时将接种于 24 孔板的细胞预先给予 NMF,d 3 时加或不加KA处理后,以台盼蓝染色鉴别并计数死、活细胞,可得出细胞的存活率。结果: NMF 明显促进胎鼠皮层神经元活性,其中 NMF1、0. 1、10nmol·L-1促进神经元活性增殖率分别高达 34.7%、37.4%、36. 7%, NMF 明显促进正常胎鼠皮层神经元存活卒,与对照组比较,10nmol·L-1 NMF 对皮层神经元的存活率分别提高 39.3%、73.5%。 NMF能显著 对抗 KA 所致的神经元损伤,与 KA 损伤组相比, NMF0.1、10、10nmol·L-1对损伤皮层神经元的保护率分别为 77.30%、80.10%、84.15%。结论: NMF 明 显促进胎鼠皮层神经元的洁性、提高正常皮层神经元,的存活卒,并能有效地保护KA所致的神经元损伤,提示 NMF 是一种很有潜力的治疗 AD 的药物。  相似文献   

18.
On the basis of energy and shape method for the determination of the valence bond (VB) structures of crystal, the valence bond structure of titanium is redetermined at room temperature and calculated in the whole temperature range of 0-1943K. The outer shell electronic distribution of Ti is e_c~(2.9907) · (s_c~(0.4980) d_c~(2.4927)) ef1.0093 in crystal. The temperature dependences of the VB structures of hcp and bcc phases are the same. The VB structures of hcp and bcc phases monotonically increase or decrease with the increase in temperature, but show discontinuous changes at the phase-transformation temperature 1155K.  相似文献   

19.
During the slab continuous casting process, the flow field of molten steel in the mold plays a decisive role in the quality of the slab. In this paper, electromagnetic swirling flow in nozzle technology is proposed to control the flow field in mold.This technology can drive molten steel to rotate inside the submerged entry nozzle by electromagnetic force, thereby controlling the flow field. This research shows that it can reduce the impact of molten steel on the bottom of nozzle and partly reduce the negative pressure at the upper part of nozzle outlet which is even eliminated by optimizing the structure and angle of nozzle. The area of heat flux of the mold wall becomes larger, and the crest value of heat flux gets lower than that without swirling in nozzle and any nozzle optimization. The meniscus fluctuates smoothly, and the flow velocity at the top surface is within a reasonable range. The temperature field distribution in the mold is uniform which was beneficial to the growth of equiaxed crystal and decreased element segregation.  相似文献   

20.
The Lanthanum-doped bismuth ferrite–lead titanate compositions of 0.5(Bi LaxFe1-xO3)–0.5(Pb Ti O3)(x = 0.05,0.10,0.15,0.20)(BLxF1-x-PT) were prepared by mixed oxide method.Structural characterization was performed by X-ray diffraction and shows a tetragonal structure at room temperature.The lattice parameter c/a ratio decreases with increasing of La(x = 0.05–0.20) concentration of the composites.The effect of charge carrier/ion hopping mechanism,conductivity,relaxation process and impedance parameters was studied using an impedance analyzer in a wide frequency range(102–106Hz) at different temperatures.The nature of Nyquist plot confirms the presence of bulk effects only,and non-Debye type of relaxation processes occurs in the composites.The electrical modulus exhibits an important role of the hopping mechanism in the electrical transport process of the materials.The ac conductivity and dc conductivity of the materials were studied,and the activation energy found to be 0.81,0.77,0.76 and 0.74 e V for all compositions of x = 0.05–0.20 at different temperatures(200–300 °C).  相似文献   

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