Anode oxidation of HCHO in THPED-containing electroless copper plating solution

The electrochemical mechanism of anode oxidation of HCHO in electroless copper plating solution with N, N, N', N'-tetrakis(2-hydroxypropyl)ethylenediamine (THPED) was investigated by measuring cyclic voltammetry curves and anodic polarization curves. Three different oxidation peaks occur at the potentials of-0.62V (Peak 1), -0.40V (Peak 2) and -0.17V (Peak 3) in the anode oxidation process of THPED-containing solution. The reaction at Peak 1, a main oxidation reaction, is the irreversible reaction of adsorbed HCHO with hydrogen evolution. The reaction at Peak 2, a secondary oxidation reaction, is the quasi-reversible reaction of adsorbed HCHO without hydrogen evolution. The reaction at Peak 3 is the irreversible oxidation of anode copper. The current density of Peak 1 increases gradually, that of Peak 2 remains constant and that of Peak 3 decreases with the increase of HCHO concentration. The current density of Peak 3 increases with the increase of THPED concentration and the complexation of THPED promotes the dissolution of anode copper.     

CTAB改性钒硅分子筛对CO-SCR低温催化脱硝性能的影响

为了提高 NO-CO低温选择性催化还原(SCR)的脱硝性能,寻找新的催化剂成为脱硝领域的重点.采用水热法制备钒硅酸盐AM-6 ,并加入表面活性剂CTAB(十六烷基三甲基溴化铵)改性,考察CTAB不同添加量对AM-6 形貌、组成结构以及选择性催化还原(SCR)性能的影响.采用 X 射线衍射仪(XRD)、傅里叶红外仪(FT-IR)、扫描电子显微镜(SEM)和 X射线光电子能谱分析(XPS)等对催化剂性能进行表征.结果表明:添加 CTAB 未引入其他杂质元素,当CTAB与 V比例为 1∶4 时,合成的 AM-6(1/4CTAB)形貌更加规整,晶体结构良好,V5+/V4+比例较为均衡,150 ℃时脱硝率达到 81.54%,相比于 AM-6 脱硝活性达到 80%的温度约降低 50 ℃.     

Recovery of copper sulfate after treating As-containing wastewater by precipitation method

The solid sodium hydroxide neutralized acidic As-containing wastewater till pH value was 6. Green copper arsenite was prepared after copper sulfate was added into the neutralized wastewater when the molar ratio of Cu to As was 2:1 and pH value of the neutralized wastewater was adjusted to 8.0 by sodium hydroxide. The arsenious acid solution and red residue were produced after copper arsenite mixed with water according to the ratio of liquid to solid of 4:1 and copper arsenite was reduced by SO₂ at 60 °C for 1 h. The white powder was gained after the arsenious acid solution was evaporated and cooled. Copper sulfate solution was obtained after the red residue was leached by H₂SO₄ solution under the action of air. The results show that red residue is Cu₃(SO₃)₂·2H₂O and the white powder is As₂O₃. The leaching rate of Cu reaches 99.00% when the leaching time is 1.5 h, molar ratio of H₂SO₄ to Cu is 1.70, H₂SO₄ concentration is 24% and the leaching temperature is 80 °C. The direct recovery rate of copper sulfate is 79.11% and the content of CuSO₄·5H₂O is up to 98.33% in the product after evaporating and cooling the copper sulfate solution.     

用MIBK萃取剂从含金铂钯的贵液中萃取金的研究

采用甲基异丁基酮(MIBK)萃取剂从含金、铂、钯的贵液中用萃取金, 研究了MIBK 萃取剂对金的萃取性能, 并探讨了其萃取机理。实验表明:在一定条件范围内, MIBK 萃取金分配比受[H⁺] 和[Au]o 的影响很小, 受相比影响较大;其萃取是按照羊盐机理萃取的, 即金在有机相中主要是以[RH⁺] [AuCl₄^-] 缔合物的形式存在;MIBK 萃取金不但速度快, 而且萃取率高, 当贵液中含金为310 mg/L, 相比为0.1(有机相/ 水相), 萃取时间为6 min 时, 其一级萃取率可达99 %以上。     

氯化钯制备过程中赶硝工艺的研究

研究了以Pd(NH3)2Cl2作原料,用水合肼还原成金属钯,王水溶解钯制备PdCl2的工艺,着重研究了采用MxOy+HCl复合赶硝剂对降低PdCl2产品中NO3-含量和赶硝过程中NO2生成的影响。结果表明,加入MxOy可大大降低PdCl2中NO3-的含量,当每公斤海绵钯加入7L(1∶1)王水,在30℃左右溶解后加入1L浓HCl和1.5LMxOy(35%)时,一次性赶硝,PdCl2中NO3-的含量<0.03%。复合赶硝剂的应用可解决采用HCl作赶硝剂,反复赶硝,不仅产生大量NO2污染环境,而且导致PdCl2产品中NO3-含量高的问题。     

Vx-Mn0.8Fe0.2O2催化剂的制备及其抗硫脱硝性能

为了更好地适应工业化脱硝需求,选用廉价的黑色金属Mn和Fe作为催化剂主要原料,通过V掺杂极大地提升了锰铁催化剂的低温脱硝性能和抗硫性能。采用共沉淀法制备了V_x-Mn_0.8Fe_0.2O₂催化剂,运用X射线衍射仪(XRD)、扫描电子显微镜(SEM)和X射线光电子能谱分析(XPS)考察了V₂O₅添加量对Mn_0.8Fe_0.2O₂催化剂的结构、形貌及其抗硫脱硝性能的影响。结果表明:V_x-Mn_0.8Fe_0.2O₂催化剂主要物相为Mn₂O₃,样品颗粒尺寸小且分散均匀。V_0.3-Mn_0.8Fe_0.2O₂催化剂具有较多的活性位点及较好的抗硫脱硝性能,在300℃时脱硝率可达90.36%,相比于Mn_0.8Fe_0.2O₂催化剂脱硝性能达到90%的温度约降低100℃;同时,在V(CO):V(NO):V(SO₂)为3:1:1的反应条件下,催化剂的脱硝率仍能保持在80%以上。     

合成交换法制备Alx/HKUST-1催化CO低温还原NO

采用合成交换法成功制备双金属铜基有机金属骨架材料Al_x/HKUST-1(x=1/24,1/12,1/6,1/3),并采用X射线衍射(XRD)、扫描电子显微镜(SEM)、比表面积分析(BET)、热重分析(TG)、红外光谱(IR)、X射线光电子能谱(XPS)以及H₂程序升温还原(H₂-TPR)技术对其进行表征。研究结果表明,Al_x/HKUST-1维持前躯体(HKUST-1)的正八面体结构,掺铝(Al³⁺)后,HKUST-1的热稳性和还原性能均得到提高。Al_1/12/HKUST-1表现出最佳的催化活性,温度为210℃时,催化脱硝率达到100%,相比HKUST-1降低了50℃。催化反应后,Al_1/12/HKUST-1中Al、Cu和O的价态种类没有发生改变,但是不同价态的Al、Cu和O的含量比值发生了明显变化。Al_x/HKUST-1的催化过程遵循Langmuir-Hinshelwood反应机理。     

铜阳极泥中回收碲及其新材料制备技术进展

对铜阳极泥回收碲的几种方法,如纯碱焙烧法、高压碱浸法、硫酸化焙烧法、氧化酸浸法、液膜分离法、溶剂萃取法、微生物法、铜粉还原法及作者发明的铜阳极泥预处理及回收稀散金属的方法作了详细介绍,并对各方法的优缺点作了分析.对高纯碲的制备方法以及碲的新材料在各方面的进行了详细的介绍.铜阳极泥是碲的主要来源之一,在铜阳极泥处理中碲多处分散,碲回收率低.采用铜阳极泥预处理并回收稀散金属,碲回收率可达到88%以上,而且金银得到富集,有利于提高金银直收率.在材料领域中的应用关键在于高纯碲的制备,碲的新材料主要为热电材料、红外探测材料、碲化镉太阳能电池,其应用前景广阔.     

高铁生物堆浸液Na2S2O3回收铜新工艺

在生物浸铜过程中,Fe3+杂质逐步积累,当堆浸液中Fe3+浓度过高时,将使铜的萃取难以进行.本研究采用硫代硫酸钠处理高铁生物堆浸液使铜得到回收,当高铁生物堆浸液Cu2+为7.41g/L、TFe为27.9 g/L、Fe3+为14.68 g/L时,在反应温度为80℃,硫代硫酸钠用量为18 g/L,反应时间为60 min条件...     

以硫铁矿烧渣为原料氯酸钠氧化法制备PFS的研究

在硫铁矿烧渣与硫酸反应所得的酸浸液中加入一定量的七水硫酸亚铁和氯酸钠 ,制备得到聚合硫酸铁 (PFS)。研究了氯酸钠氧化法制备 PFS的影响因素。该方法工艺简单 ,反应时间短 ,无催化剂 ,并具有对环境友好和一定的经济效益。