络合-超滤-电解集成过程处理重金属工业废水Ⅱ电沉积回收重金属

系统地研究了络合 -超滤耦合过程处理重金属废水的超滤浓缩液中重金属的电沉积回收。选用性能优异、价格低廉的平板石墨为电极 ,以传统的电解槽为反应器 ,详细地探讨了从稀水溶液中回收 Cu和 Zn重金属的各种因素对电沉积效果的影响 ,确定了最佳的工艺条件。在最佳的工艺条件下 ,电沉积回收 Cu和 Zn的电流效率均可达到 60 %以上 ,而电能消耗分别为 1 1 .5 k W· h/kgCu,1 4.0 k W· h/kg Zn。     

杂质Zn,Fe和Cu对BMIC-AlCl3离子液体电解精炼铝的影响

研究了摩尔比为1:2的BMIC-AlCl3离子液体中杂质元素Zn, Fe和Cu对电解精炼铝的影响. 结果表明,离子液体中Zn(II)/Zn, Fe(II)/Fe和Cu(I)/Cu相对于Al(III)/Al的平衡电极电势分别为0.21, 0.63和0.64 V,比其标准电极电势相对值小得多;在温度80℃和电流密度100 A/m2条件下进行电解精炼,铝合金阳极中的绝大部分Zn, Fe和Cu杂质被去除,阴极铝沉积层中杂质含量随阳极杂质含量增加而升高,但杂质的贫化率降低,电流效率均超过94%,能耗为1.59~1.74 kW×h/kg;电解精炼铝含量为75.3%(w)工业铝合金得到了纯度超过99.8%的金属铝,且沉积层致密平整.     

络合超滤过程处理重金属工业废水

以废水回用为目的,研究了络合 超滤耦合过程处理重金属工业废水。利用聚丙烯酸(PAA)为络合剂和含Zn2+和Cu2+的重金属废水,讨论了各种因素,如操作压力、膜面流速、重金属与络合添加剂的质量比、pH、体积浓缩因子对超滤过程的影响。在NaCl或Na2SO4存在的条件下,对Zn2+和Cu2+仍可达到100%的去除。在较高的离子强度下,如0.203mol/L时,对Zn2+和Cu2+的截留率仍可达到95%以上。经过浓缩的重金属废水,可回收重金属,而透过液可达到回用水的标准。     

浅谈目前氯碱行业变电系统的节能途径

电力在氯碱企业处于原料位置,每吨烧碱的交流电耗一般在2500kW·h～2600kW·h之间;1万t/a烧碱的平均电负荷为3000kW左右。以烧碱规模4万t/a的氯碱厂为例,年用电量就在1亿kW·h以上,电负荷便在15000kW以上。何况4万t/a规模的厂子在行业中还算是“小弟弟”。     

络合-超滤-电解集成过程处理重金属工业废水 Ⅰ络合-超滤耦合过程

以废水回用为目的 ,研究了络合 -超滤耦合过程处理重金属工业废水。利用聚丙烯酸( PAA)为络合剂和含 Zn2 + 和 Cu2 + 的重金属废水 ,讨论了各种因素 (如操作压力 (Δp)、膜面流速( VL)、重金属浓度与络合剂添加浓度比 ( L)、p H、体积浓缩因子 ( VCF) )对超滤过程的影响。在 Na Cl或 Na SO4存在的条件下 ,对 Zn2 + 和 Cu2 + 仍可达到 1 0 0 %的去除。在较高的离子强度下 ,如离子强度为 0 .2 0 3mol/L时 ,对 Zn2 +和 Cu2 +的截留率仍可达到 95 %以上。经过浓缩的重金属废水 ,可回收重金属 ,而透过液可以达到回用水的标准     

生活污泥焚烧灰的重金属含量及其浸出特征

为了探讨生活污泥焚烧灰中重金属的含量及其浸出特征,收集了广州沥窖污水处理厂的剩余污泥,采用火焰原子吸收光谱法测量重金属含量;应用固体废物浸出毒性的浸出方法(GB5086.2-1997),以不同p H的浸提剂,对污泥中重金属的浸出特性进行了实验研究。结果表明:污泥中Fe的含量最高,达到27378 mg/kg,其次是Mn和Cu,分别为436.5 mg/kg和315.2 mg/kg,Zn、Cr、Pb和Ni的含量较高,依次是721.5、199.2、122.2和110.8 mg/kg,Cd的含量极少,仅有0.33 mg/kg。Cr和Cd金属元素的8小时浸出量分别为62.9 mg/kg、0.96 mg/kg,其余被测的金属元素:Fe、Pb、Cu、Ni、Zn以及Mn,在任何浸提时间下,其浸出量均为0 mg/kg。本实验中重金属在酸性条件下的浸出率明显高于碱性条件下,Cr、Ni和Cd的最佳浸提剂p H值均为2。其中Cu和Zn随浸提剂p H变化的浸出特征不明显。。     

双极性膜电渗析技术在酒石酸生产中的应用研究

实验验证了二室式和三室式双极性膜电渗析法用于从酒石酸盐制备酒石酸过程的可行性。系统研究了制备过程中的电流效率、能耗、产品浓度和纯度等技术指标。结果表明 ,在酒石酸钠 (或钾 )的转化率达 97%时 ,电流效率在 80 %以上。平均电耗为 2 .31kW·h/kg(二室式 )和 7.0 4kW·h/kg (三室式 )。     

离子交换-电沉积联合工艺对电镀废水的处理研究

采用离子交换-电沉积联合工艺处理含铜电镀废水,考察了各相关因素对处理效果的影响。结果表明,离子交换处理中,pH=4时D402树脂对铜离子去除率最大;流速为6 BV/h时,穿透时间为213.1 min;用质量分数为10%的硫酸作为解吸剂,解吸率可达95.9%。对树脂吸附饱和后解吸的再生液进行电沉积回收铜,在电流密度210 A/m2、温度60℃、pH为0.8、极板间距15 mm的条件下,对450 mL初始Cu2+质量浓度为10 380 mg/L的再生液电解4 h,铜回收率可达94.8%,电流效率62.2%,沉积Cu的质量分数为99.7%。离子交换-电沉积工艺不仅可以保证出水达标排放,而且可以回收铜。     

碳材料改性锌负极的复合锌离子电池电化学性能的研究

采用涂布法分别将碳纳米管(CNT)和氧化石墨(GO)涂布在铜箔(Cu)上制成Cu/CNT和Cu/GO复合集流体,随后在复合集流体表面电沉积锌(Zn)制成Cu/CNT/Zn和Cu/GO/Zn复合电极作为锌负极,并通过扫描电子显微镜(SEM)观察微观形貌。结果表明,可以发现锌在两种复合集流体上均为不规则片状,且由于氧化石墨的尺寸大于碳纳米管,其表面的锌片尺寸也略大于碳纳米管表面的锌片尺寸。在电流密度为0.5 mA/cm²的循环测试中,Cu/CNT/Zn||Cu/CNT/Zn复合对称电池保持极化电压在0.02 V以内正常运行了50 h,而Cu/GO/Zn||Cu/GO/Zn复合对称电池保持极化电压在0.04 V以内正常运行了160 h。在全电池的电化学性能测试中, MnO_2||Cu/CNT/Zn和MnO_2||Cu/GO/Zn复合锌离子电池均表现出高于MnO_2||Zn电池的容量。     

论水泥工业能源消耗控制战略

一、水泥工业能源消耗的基本状况水泥生产包括生料均化、生料粉磨、熟料煅烧和泠却、水泥粉磨及水泥包装和发送等多个工艺过程,各个工艺过程都需要一定量的电耗见表1。依据工艺技术条件,各个工艺过程的电耗会在一定范围内变化。例如,采用立磨的生料粉磨系统的平均电耗为16kW·h/t,而采用球磨机的生料粉磨系统的平均电耗为20kW·h/t,两者相差4kW·h/t。另一方面,技术先进的大型球磨机的生料粉磨系统的电耗可低于17kW·h/t,而落后的小型球磨机的生料粉磨系统的电耗可高达25kW·h/t,两者相差8kW·h/t。由于技术水平的不同,水泥生产综合电耗…     

Antibacterial Properties of Ester—Cross-Linked Cellulose–Containing Fabrics Post-Treated with Metal Salts

To improve the performance properties of cellulose-containing fabric, ester was cross-linked with polycarboxylic acid in the presence of specific catalysts. Its pendant carboxyl groups were exploited in binding some heavy metals (by reacting with some salts, such as zinc acetate, zinc chloride, zinc sulfate, cupric acetate, cupric chloride, cupric sulfate, and nickel sulfate) capable of imparting their antibacterial activity toward some gram-positive bacteria (viz., B. subtilis, B. mycoides, Sta. aureus) and a gram-negative bacteria (E. coli). Zinc salts impart to the fabric the highest antibacterial activity, followed by cupric acetate. Zinc chloride proved to be the metal salt that yielded the maximum antibacterial activity.     

电解法制备高纯异辛酸亚锡的研究

金属锡为阳极，阴极为钛网，电解温度为７０℃，槽电压为６．５Ｖ，电解９０ｍｉｎ，电流效率为６９．１％，与异辛酸的转化率为９８．６％，异辛酸亚锡产率为９５．２％，耗电量为１．２０ｋ·ｈ／ｋｇ。     

采用液化天然气冷量的空分系统新流程

从多个角度分析了空分装置中应用液化天然气(LNG)冷量的优势,针对不同的场合提出了2种引进LNG冷量的液体空分流程新方案。方案1适用于投资建设新设备的场合,方案2适用于现有流程的改造生产液体的场合,2种方案有一个共同点即使用LNG冷量冷却循环氮气制冷。采用Aspen P lus软件对2个方案进行了模拟计算,结果表明:引进LNG冷量之后,所需循环氮气量明显减少,系统最高运行压力降低由传统流程的4.2—5.0 MPa降低到2.1—2.6 MPa,液态产品的单位能耗从约0.5 kW.h/kg降低到0.327—0.338 kW.h/kg,节能效果明显。LNG气化过程中换热压力的提高对冷量回收影响较小,而采用液泵加压节省能耗,将气化过程安排在升压过程之后有利于能源的合理利用。     

Separation and recovery of heavy metals from concentrated smelting wastewater by synergistic solvent extraction using a mixture of 2-hydroxy-5-nonylacetophenone oxime and bis(2,4,4-trimethylpentyl) -phosphinic acid

Extraction and separation of copper, zinc, nickel, and cadmium from calcium and magnesium in concentrated smelting wastewater by synergistic solvent extraction using a mixture of 2-hydroxy-5-nonylacetophenone oxime (Mextral 84H) and bis(2,4,4 -trimethylpentyl)-phosphinic acid (Cyanex 272) in an aliphatic diluent (DT-100) was studied. The effects of extractant concentrations, equilibrium pH, organic-to-aqueous phase ratios, system temperature, and extraction and stripping efficiencies on the extraction performance of the heavy metals were investigated. Extraction of pH isotherms showed that addition of Cyanex 272 to Mextral 84H causes obvious synergistic shifts for zinc and cadmium and a slightly antagonistic shift for nickel. The separation factor of cadmium over magnesium was 155.7 and the ΔpH₅₀ values between the metals were over 1.00 pH units. Semi-continuous tests for the metals extraction, scrubbing, and stripping were conducted in a continuous extraction apparatus with conditions further optimized for separation of the metals. Nearly 100% of the copper and nickel and over 98% of the zinc and cadmium were recovered with less than 0.1 mg/L copper and nickel, 26 mg/L of zinc, and 10 mg/L of cadmium remaining in the raffinate. A process in which all valuable metals are extracted simultaneously and stripped selectively at optimal conditions is proposed that is entirely feasible for the separation of copper, zinc, nickel, and cadmium from calcium and magnesium in concentrated smelting wastewater. The study determines the fundamental parameters for the treatment of smelting wastewater by solvent extraction.     

The separation and recovery of copper(Ⅱ), nickel(Ⅱ), cobalt(Ⅱ), zinc(Ⅱ),and cadmium(Ⅱ) in a sulfate-based solution using a mixture of Versatic 10 acid and Mextral 984H

We studied the separation and recovery of copper(Ⅱ), nickel(Ⅱ), cobalt(Ⅱ), zinc(Ⅱ), and cadmium(Ⅱ) from magnesium and calcium, using synergistic solvent extraction(SSX) in a typical hydrometallurgical waste solution. A mixture of Versatic 10 acid and Mextral 984 H, diluted with Mextral DT100, was used to obtain fundamental data on p H and distribution isotherms, as well as the kinetics of extraction and stripping. We also investigated the main effects and interactions of common solvent extraction factors: the extraction p H at equilibrium, the temperature, and the extractant concentration. The synergistic effect for extracting metals was confirmed. The results showed that the addition of Mextral 984 H enhanced the separation factors of copper, nickel, cobalt,zinc, and cadmium over magnesium and calcium. Compared with Versatic 10 acid alone, for a mixture of0.5 mol·L~(-1) Versatic 10 acid/0.5 mol·L~(-1)Mextral 984 H, Δp H50 values of copper, nickel, cobalt, zinc, and cadmium were found to be N 2.0, 3.30, 2.85, 0.95, and 1.32 p H units, respectively. The Δp H_(50)(Zn–Mg)and Δp H_(50)(Zn–Ca)values were 3.27 and 2.25, respectively, indicating easy separation and recovery of copper, nickel, zinc, cobalt,and cadmium. The extraction and stripping of copper, cobalt, zinc, and cadmium were fast, with 90% of the metal transferred in 2 min. We next studied whether the metals could be stripped from the extracted liquid selectively in sequence, by using sulfuric acid at different concentrations. The influence of the molecular structure of the oxime and carboxylic acid components upon the synergistic effects was identified by numerical analysis.Excellent separation of copper, nickel, cobalt, and zinc over magnesium and calcium was achieved with this synergistic solvent extraction system.     

Simple separation method of Zn(Ⅱ) and Cd(Ⅱ) from brine solution of zinc plant residue and synthetic chloride media using solvent extraction

In this work, the possibility of separation of Zn~(2+) and Cd~(2+) metal ions from chloride(brine) solutions was examined. For this purpose, simple solvent extraction(SX) experiments by di-2-ethylhexyl phosphoric acid(D2EHPA)in kerosene as a diluent was performed on synthetic and industrial chloride solution obtained from brine leaching of zinc filter cakes(by-product of zinc hydrometallurgical processing). The optimal conditions for separation were determined. The zinc extraction efficiency was 99% with negligible co-extraction of cadmium.Therefore, a high ΔpH_(0.5) value for Zn(Ⅱ) and Cd(Ⅱ) was achieved. FT-IR and slope analysis indicated that ZnClA·3HA and CdClA·3HA species were probably extracted.     

山东淄博通宇聚酯试生产及流程改进

介绍瑞士伊文达四釜流程20万t/a聚酯项目的试车过程以及4年来的运行状况和工艺设备改进之处。该工程吸纳了专利公司的许多改进之处,形成了装置的工艺设备特点,一次投料试车成功;在110%的负荷下,PTA、EG、电的单耗分别为856kg/t、334kg/t、88kW·h/t。在工艺设备改进方面给同类厂家提供了参考。     

铁氧体法去除废水中的镍、铬、锌、铜离子

采用铁氧体法处理含镍、铬、锌、铜的废水,研究了pH及硫酸亚铁投加量对重金属离子去除效果的影响.对于镍、锌、铜离子,最佳絮凝pH分别为8.00～9.80、8.00～10.50和10.00,投加的亚铁离子与其摩尔比均为2～8;六价铬的最佳还原pH为4.00～5.50,最佳絮凝pH则为8.00～10.50,最佳投料比为20....     

多孔电极中氧的阴极还原制备过氧化氢

把炭黑与PTFE乳液混和制成多孔电极.在用阳离子膜分隔两电极的电解池中,当KOH的浓度大于0.3mol/1时,20℃下产生HO-_2的电流效率超过90%.每公斤过氧化氢耗电2.2kW·h.     

垃圾焚烧飞灰水洗脱氯及重金属浸出特性研究

系统研究了机械炉排炉垃圾焚烧飞灰水洗过程中氯化物和重金属的浸出特性,并采用Visual MINTEQ模拟分析水洗液中重金属的存在形态。结果表明：飞灰中的氯主要以可溶性氯化钠（NaCl）、氯化钾（KCl）、氯化钙（CaCl₂）、碱式氯化钙（CaClOH）的形式存在,飞灰水洗浸出成分97%以上为氯离子（Cl^-）、钠（Na）、钾（K）、钙（Ca）,其中氯离子占比高达60%;重金属及其他成分的浸出量很少,不足1%。水洗对氯离子的去除效果非常明显,可达92%以上,但是重金属的浸出量极低。飞灰单次水洗最佳条件：液固体积质量比为6 mL/g,洗涤时间为10 min。Visual MINTEQ模型分析表明,pH是控制飞灰水洗液中铅（Pb）、铜（Cu）、锌（Zn）、镉（Cd）形态的重要因素,氯离子（Cl^-）对镉的形态分布也有着重要的影响。飞灰水洗液电导率与氯离子质量浓度具有极好的线性相关性,其可作为监测滤液中氯离子质量浓度变化的有效间接指标。