Dechlorination of carbon tetrachloride by the catalyzed Fe-Cu process

The dectrochemical reduction characteristics of carbon tetrachlofide （CT） were investigated using cyclic voltammetry in this study. In addition, the difference in reduction mechanisms of CT between Master Builders＇ iron and the catalyzed Fe-Cu process was discussed. The results showed that CT was reduced directly on the surface of copper rather than by atomic hydrogen produced at the cathode in the catalyzed Fe-Cu process. The reduction was realized largely by atomic hydrogen in Master Builders＇ iron. The entire CT in 350 ml aqueous solution with 320 mg/L was reduced to trichloromethane and dichloromethane in 2.25 h when 100 g of scrap iron with Fe/Cu ratio of 10：1 （w/w） were used. Moreover, the reduction rate slowed with time. CT could be reduced at acidic, neutral and alkaline pH from solution by Fe-Cu bimetallic media, but the mechanisms were different. The degradation rate was not significantly influenced by pH in the catalyzed Fe-Cu process; in Master Builders＇ iron it clearly increased with decreasing pH. The kinetics of the reductions followed pseudo-first order in both cases. Furthermore, the reductions under acidic conditions proceeded faster than that under the neutral and alkaline conditions. The catalyzed Fe-Cu process was superior to Master Builders＇ iron in treating CT-containing water and this advantage was particularly noticeable under alkaline conditions. The reduction was investigated in the cathode （Cu） and anode （Fe） compartments respectively, the results showed that the direct reduction pathway played an important role in the reduction by the catalyzed Fe-Cu process. The catalyzed Fe-Cu process is of practical value.

Electrochemical reduction characteristics and mechanism of nitrobenzene compounds in the catalyzed Fe-Cu process

The reduction of the nitrobenzene compounds （NBCs） by the catalyzed Fe-Cu process and the relationship between the electrochemical reduction characteristics of NBCs at copper electrode and reduction rate were studied in alkaline medium（pH=11）. The catalyzed Fe-Cu process was found more effective on degradation of NBCs compared to Master Builder＇s iron. The reduction rate by the catalyzed Fe-Cu process decreased in the following order： nitrobenzene 〉4-chloro-nitrobenzene ≥m-dinitrobenzene ：〉 4-nitrophenol ≥2,4-dinitrotoluene 〉2-nitrophenol. The reduction rate by Master Builder＇s iron decreased in the following order： m-dinitrobenzene ≥4-chloro-nitrobenzene 〉4-nitrophenol 〉2,4-dinitrotoluene ≈nitrobenzene 〉2-nitrophenol. NBCs were reduced directly on the surface of copper rather than by the hydrogen produced at cathode in the catalyzed Fe-Cu process. The reduction was realized by the hydrogen produced at cathode and Fe（OH）2 in Master Builder＇s iron, It is an essential difference in reaction mechanisms between these two technologies. For this reason, the reduction by the catalyzed Fe-Cu depended greatly on NBC＇s electron withdrawing ability.

Multivariate Statistical Process Monitoring of an Industrial Polypropylene Catalyzer Reactor with Component Analysis and Kernel Density Estimation

Abstract Data-driven tools, such as principal component analysis （PCA） and independent component analysis （ICA） have been applied to different benchmarks as process monitoring methods. The difference between the two methods is that the components of PCA are still dependent while ICA has no orthogonality constraint and its latentvariables are independent. Process monitoring with PCA often supposes that process data or principal components is Gaussian distribution. However, this kind of constraint cannot be satisfied by several practical processes. To ex-tend the use of PCA, a nonparametric method is added to PCA to overcome the difficulty, and kernel density estimation （KDE） is rather a good choice. Though ICA is based on non-Gaussian distribution intormation, .KDE can help in the close monitoring of the data. Methods, such as PCA, ICA, PCA.with .KDE（KPCA）, and ICA with KDE,（KICA）, are demonstrated and. compared by applying them to a practical industnal Spheripol craft polypropylene catalyzer reactor instead of a laboratory emulator.

LCA studies for alkaline and enzyme catalyzed biodiesel production from palm oil

The life cycle analysis of biodiesel production from palm oil (PO) involves 3 stages: 1) Cultivation;2) Oil Extraction and 3) Transesterification of PO. There are several different approaches to the production process. The enzyme catalyzed process, was investigated and its environmental performance was compared with the conventional alkali-catalyzed process by using life cycle analysis (LCA). The enzyme catalyzed process is found to be technically a simpler production process and offers the production of less environmentally damaging wastes.

Fe-Cu催化还原法处理硝基苯类化合物废水

以硝基苯、4-氯硝基苯、4-硝基苯酚与2-硝基苯酚为目标污染物,对比了铁单独处理和铁铜联合处理的效果,并研究了硝基苯与4-氯硝基苯、4-硝基苯酚、2-硝基苯酚双组分混合以及2-硝基苯酚与4-硝基苯酚双组分混合状态下,Fe-Cu催化还原体系降解各组分的效果和相互影响.结果表明:铜可以催化铁屑法对硝基苯的还原;无论是单一组分还是混合状态下,硝基苯类化合物的催化还原降解反应均符合准一级反应动力学;除2-硝基苯酚以外,其他硝基苯类化合物均是以混合状态存在时催化降解速率比其单独存在时的慢;在双组分混合溶液中,另一种化合物对硝基苯催化还原降解产生的抑制作用大小为:2-硝基苯酚>4-硝基苯酚>4-氯硝基苯.化合物的扩散速率越快,表面反应速率越慢时,它对混合溶液中其他共存硝基苯类化合物的催化还原反应速率抑制作用越大.

Stability analysis of alkaline nitrobenzene-containing wastewater by a catalyzed Fe-Cu treatment process

Iron and copper bimetallic system(catalyzed Fe-Cu process)is a promising technology for alkaline nitrobenzene-containing wastewater treatment.However,little is currently known about the changes of treatment efficiency with time going.This research investigated the long-term performance of the catalyzed Fe-Cu process to reduce nitrobenzene(NB)in alkaline wastewater.In addition,the changes of the metal surfaces morphologies and matters before and after the reaction were analyzed by scanning electron microscopy(SEM)in conjunction with energy-dispersion spectroscopy(EDS)and X-ray diffraction spectros-copy(XRD).The results showed that the surface properties of copper almost remained unchanged after weeks of operation,which spelled its strong chemical stability and resistance to poisoning.Moreover,the results indicated that there were two reasons for the treatment efficiency decreasing with time.One was the gradual iron element consumption due to corro-sion.The other was iron reactivity weakened due to the precipitates accumulation on the surfaces that were mainly Fe_(3)O_(4) and FeCO.

我国煤温和气化(热解)焦油性质及其加工利用现状与进展

煤的温和气化（热解）技术是洁净煤技术的重要内容之一。采用该工艺对低阶煤进行加工转化，可同时获取多种用途广泛、有经济价值的煤基产品，从数量和质量上较好地利用了煤资源，技术上和经济上易于实现不同层次的开发和生产，是该类煤种综合利用的有效途径。分析总结了国内主要的煤热解工艺，特别是较典型的热解工艺焦油产物的基本性质。在此基础上，对我国目前低阶燥热解焦油的加工利用现状及进展进行了阐述和比较分析。认为加氢制取机动车燃料油是此类焦油深加工的有效途径之一，同时指出应关注其中＞36℃的重焦油类的加工利用、酚类化合物的提取利用和热解焦油沥青的深加工与有效利用。

浸出黄铜矿的新工艺研究

研究了银离子催化、过硫酸铵浸出黄铜矿的新工艺及机理,并分析和讨论了浸出温度、浸出时间、过硫酸铵浓度、粒度、银离子浓度、pH等因素对浸出率的影响。试验结果表明,在过硫酸铵初始浓度0.50mol/L、黄铜矿粒度-74+58μm、浸出温度368K、浸出时间100min、搅拌转速600r/min和矿浆密度25g/L的浸出条件下,铜的浸出率可达到98.00%以上。对浸出渣分别采用电子探针和XRD进行表征,发现加入的银离子以硫化银的形式均匀残留在渣中,且有大量元素硫产生并均匀地分布在浸出渣中;此外,原料中的黄铁矿仍残留在渣中,说明在浸出试验中没有随黄铜矿一起被浸出。机理分析表明,浸出过程中加入的微量Ag+与黄铜矿反应生成Ag2S,并能均匀夹杂在产物硫层中,改善了元素硫层的导电性能,是加快了反应速度的主要原因。

银离子在细菌浸出黄铜矿中的催化行为研究

对银离子催化细菌浸出黄铜矿进行了研究。在银离子存在下 ,矿粒越细 ,浸出率就越高 ;浸出溶液pH值在 1.5～ 2时浸出率较高 ;银离子浓度在 10mg/L时浸出效果最好。在实验范围内 ,不论银离子初始值大小如何 ,银离子在加入浸出体系后主要是以硫化银形式存在 ,以离子形式存在于溶液中只占很小一部分。

微曝气催化铁内电解法预处理化工废水

采用微曝气催化铁内电解法处理桃浦工业区混合化工废水,中试结果表明,该预处理工艺具有显著的脱色效果(平均脱色率为43%),对COD、PO3-4-P和TP的平均去除率分别高达54.5%、87.5%和79.4%。采用微曝气催化铁内电解法预处理对进水起到了缓冲和水质调节的作用,可提高整个系统的抗冲击负荷能力和运行稳定性。

4,6-二氨基间苯二酚盐酸盐合成研究

以三氯苯为原料,经硝化、水解和催化加氢三步反应,合成聚对苯撑苯并双噁唑(PBO)单体4,6-二氨基间苯二酚盐酸盐(DADHC)。研究了各中间体和单体合成中的影响因素,确定了各步反应的最佳工艺参数。对合成的各中间体和单体采用元素分析(EA)、傅立叶变换红外光谱(FT-IR)、氢核磁(1H NMR)、碳核磁(13C NMR)和高效液相色谱(HPLC)等方法进行了表征分析。结果表明,各中间体和单体均达到预定要求,纯度和收率较高。研制了一套单体防氧化分离Pd/C过滤装置,实现了Pd/C催化剂的回收再利用,解决了单体易氧化、Pd/C易失活难题,提高了生产效率,降低了生产成本。

酶促合成油酸香茅醇酯的超临界连续反应-分离过程

将固定床动态酶促反应过程和超临界二氧化碳萃取分离过程相耦合,设计并建立了一套超临界相反应分离一体化的实验装置。在该装置上初步考察了反应压力和温度对脂肪酶催化油酸甲酯和外消旋香茅醇酯交换反应的影响。结果表明,我们所建立的反应装置能有效地实现反应分离一体化过程;当体系压力接近二氧化碳的临界压力时反应速率最高;9MPa压力下反应温度为328K时反应转化率最高,而在14MPa压力下反应转化率在308K～328K之间随着温度的升高而增大。

DO对催化铁内电解预处理混合化工废水的影响

上海市西北某工业区排放的污水以化工和医药废水为主，其水量占排放总量的75％以上，属于典型的混合化工废水。目前该区的污水处理厂采用SBR工艺，但出水水质达不到有关的排放标准，尤其是色度超标严重。为此，开展了催化铁内电解法预处理该混合化工废水的生产性试验研究。结果表明，溶解氧浓度对预处理效果影响较大，在缺氧（DO〈0．5mg／L）条件下，对色度的去除效果较为明显，平均去除率可达42％，但对COD的平均去除率仅为14％左右；在高氧（DO=5．3～5．9mg／L）条件下，对COD的平均去除率可达44％左右，对色度的平均去除率为34％；在低氧（DO=0．9～1．4mg／L）条件下，对COD的平均去除率可达54．5％，对色度的平均去除率为43％，是比较理想的工况。

催化铁内电解/生物膜法处理化工废水

化工废水因含有难降解和对生物有抑制性的物质而较难处理,为此以某工业区的化工废水为研究对象,考察了催化铁内电解/悬浮填料生物膜法的处理效果,并同现有工艺进行比较。结果表明,催化铁内电解可提高废水的可生化性,整个工艺对COD、BOD5、NH3-N、色度等的去除效果较现有工艺有明显改善。

自催化乙醇法制浆最新研究进展

介绍了溶剂法制浆和自催化乙醇法的起源、定义和基本原理,重点论述了乙醇法制浆工艺、蒸煮历程、脱木素机理以及动力学等方面的研究成果,总结了多种木材和非木材原料乙醇法制浆工艺及机理。

催化还原法处理硝基苯废水的技术经济分析

采用Fe-Cu催化还原法处理硝基苯废水，优化了Cu和Fe的投加比例，并对反应过程中溶液pH值的变化，铁离子质量浓度的变化，铁的耗量和铜的溶出量进行分析．结果表明：Cu和Fe的质量比在0．2左右较为适宜；初始pH值为3．0～10．0的硝基苯废水，经该工艺处理后其pH值基本稳定在8．1左右；铁的溶解消耗量随着溶液初始pH值的降低而增大，但在30mg·L^-1之内；铁的总消耗量随着溶液初始pH值的升高而增大，但在50mg·L^-1以内；铜基本不发生溶出．与用铁碳内电解法处理工艺相比，采用本工艺处理硝基苯废水具有运行管理方便、铁的消耗量少、费用低和效果好等优点．

钨酸催化氧化环己醇合成己二酸

以钨酸-酸性添加剂为催化体系,在无有机溶剂和相转移剂的情况下,催化30%过氧化氢氧化环己醇合成己二酸。结果表明,当钨酸用量为2．5mmol,钨酸：酸性添加剂：环己醇：过氧化氢为1：1：40：176(摩尔比)时,酸性添加剂中,以磺酸水杨酸氧化环己醇效果最佳,反应8h己二酸分离产率达87．8%、纯度为99．9%；而单独以钨酸为催化剂时,己二酸分离产率达65．6%、纯度为97．3%；以酚类-弱酸性化合物为添加剂时,己二酸分离产率均在80%以上。钨酸-磺酸水杨酸催化体系重复使用至第5次,己二酸分离产率仍可达81．5%。

锰砂催化电化学方法对染料K2G脱色效果的研究

研究了锰砂催化电化学方法对偶氮染料K2G的脱色效果 .结果表明 ,锰砂中的主要成份MnOOH对电化学过程具有催化作用 ,可有效地提高染料的脱色效率 .对锰砂的X光衍射实验证明 ,反应过程中MnOOH的含量无较大变化 .染料溶液的起始pH值对其脱色率没有明显的影响 .在最佳电流密度di 为 0 2 6A·dm- 2 ,Na2 SO4 浓度为0 0 1mol·l- 1时 ,电解 70min ,浓度为 1 0 0mg·l- 1的染料K2G的脱色率能达到 99% .

组合Fenton法处理弹药销毁废水

采用Fenton氧化-活性炭吸附的组合工艺处理兰州军区某弹药试验站弹药销毁废水,通过现场的中试试验,系统考察了4个主要影响因子:H2O2浓度、Fe2+浓度、pH值及反应时间在Fenton氧化中对弹药销毁废水处理效率的影响,分析了各影响因子的作用机制,并确定了它们的最佳运行参数,即H2O2的浓度为0.1 mol/L,Fe2+的浓度为1.8 mmol/L,pH值为3.5,反应时间为8 h。结果表明这些因子对弹药销毁废水的处理效率均有较大影响,应严格控制。经组合Fenton法处理后,TNT、COD的质量浓度分别小于1、60 mg/L,色度小于5倍,达到了GB14470.3-2002标准中规定的污染物排放标准。

本体聚合稀土异戊橡胶的加工性能

对2L釜合成的5个本体聚合稀土异戊橡胶(LnIR)胶样([η]=2.38～8.10 dL/g)的辊筒行为、挤出行为,硫化特性和硫化胶性能进行了研究。结果表明,LnIR具有明显的素炼降解行为,混炼辊筒温度不宜低于70℃,混炼行为与NR和溶液聚合钛系异戊橡胶(IR-10)相当,在110～130℃时,胶料的挤出性能可达良级;口型膨胀(B)位随温度和生胶[η]的增大而略有增加,在[η]相同时,B值与IR-10胶料相近。但小于NR胶料。硫化湿度为143℃时,LnIR硫化胶的性能除拉伸强度和扯断伸长率外,其他均对硫化时间不敏感,从综合性能考虑,硫化时间应为20～40min,LnIR硫化胶的拉伸强度和撕裂强度稍低于IR-10和NR硫化胶,而回弹性、低温性能、生热和抗湿滑性等均优于或相当于后两者。为获得良好综合性能的硫化胶。LnIR[η]应为4.0～6.0dL/g。