Thermoelectric Properties of NdGd<Subscript>1+<Emphasis Type="Italic">x</Emphasis></Subscript>S<Subscript>3</Subscript> Prepared by CS<Subscript>2</Subscript> Sulfurization

Ternary rare-earth sulfides NdGd_1+x S₃, where 0 ≤ x ≤ 0.08, were prepared by sulfurizing Ln₂O₃ (Ln = Nd, Gd) with CS₂ gas, followed by reaction sintering. The sintered samples have full density and homogeneous compositions. The Seebeck coefficient, electrical resistivity, and thermal conductivity were measured over the temperature range of 300 K to 950 K. All the sintered samples exhibit a negative Seebeck coefficient. The magnitude of the Seebeck coefficient and the electrical resistivity decrease systematically with increasing Gd content. The thermal conductivity of all the sintered samples is less than 1.9 W K⁻¹ m⁻¹. The highest figure of merit ZT of 0.51 was found in NdGd_1.02S₃ at 950 K.     

FH98、3963、3881催化剂在加氢装置中的应用

介绍了FH98、3963、3881催化剂在延炼40万t／a柴油加氢装置中的装填、干燥、硫化、初活性稳定及正常使用等情况,并通过对反应前后物料的凝点、闪点、十六烷值等性能变化进行了技术分析和总结,对该催化剂的使用效果进行了评价,为该系列催化剂的装置应用积累了数据和经验。     

Hot corrosion studies of a salt-coated Ni-based superalloy under flowing wet air and sulfur vapor ambient

Corrosion of a salt-coated Ni-superalloy has been studied at 900°C under a wet air and sulfur vapor ambient. The corrosion thickness, after an incubation of ~60 hr, linearly increases with the corrosion time t and the onset of surface spallation occurred at t ≈ 60 hr. The corroded layer consists of a corrosion front dominated by Cr₃S₄ scales and linear precipitate structures, an inner corrosion layer dominated by Ni₃S₂ and NiO, and an outer corrosion layer dominated by Al₂O₃ networks surrounding the Ni₃S₂ and/or NiO scale structures. The corrosion mechanism is discussed based on the coexistence of H₂O, sulfur, and oxygen.     

High-temperature sulfurized synthesis of MnxCd1-xS composites for enhancing solar-light driven H2 evolution

In recent years, tremendous efforts have been devoted to develop new photocatalyst with wide spectrum response for H₂ generation from water or aqueous solution. In this paper, Mn_xCd_1-xS composites were in-situ fabricated via the high-temperature sulfurization to enhance the solar-light photocatalytic capacity of H₂ evolution. Benefiting from the S defects and junction interface between MnS and CdS, Mn_xCd_1-xS composites exhibited the better H₂ evolution rate than pure MnS. The H₂ evolution rate of optimal Mn_0.5Cd_0.5S with a Mn(II) content of 22.52% and a Mn/Cd mole ratio of 0.95:1 was 9.27 mmol g^?1 h^?1, which was 35.65 and 2.38 times higher than pure MnS (0.26 mmol g^?1 h^?1) and CdS (3.89 mmol g^?1 h^?1), respectively. In addition, H₂ evolution capacity of Mn_0.5Cd_0.5S decreased from 44.83 to 41.66 mmol g^?1 after three cycles. Mn_0.5Cd_0.5S prepared via the high-temperature sulfurization was thus a potential material for solar-light induced H₂ generation.     

含锰反萃液制备高纯碳酸锰工艺研究

以含锰反萃液为原料,经针铁矿法除铁、硫化除重金属、碳化、洗涤制备了合格高纯碳酸锰。考察了终点pH、反应温度对除铁率的影响和(NH4)2S加入量、温度、反应时间对重金属去除率的影响,结果表明:在pH=4.0、反应温度95℃的条件下可将铁除至1.5 mg/L以下;除铁滤液加入2.2倍计量比的(NH4)2S,在反应温度35℃、反应时间60 min的条件下,Ni、Co、Zn可降低至1 mg/L以下;除重金属滤液加入碳酸氢铵调节pH在7.0~7.2,过滤、洗涤,获得满足HG/T 2836—2011(Ⅰ型)产品标准的合格高纯碳酸锰,锰回收率为93.9%。     

预氧化对一种镍基单晶高温合金的热腐蚀影响

为了解预氧化对镍基单晶高温合金的短时热腐蚀影响,采用涂盐法研究了一种高温合金经预氧化后在Na₂SO₄-NaCl盐膜条件下的热腐蚀行为,测量了不同预氧化处理时间合金的腐蚀动力学曲线,借助扫描电子显微镜(SEM)观察了合金腐蚀层截面的微观组织,并利用X-射线衍射仪(XRD)确定相结构.结果表明：未经过预氧化处理的合金表面腐蚀严重,热腐蚀增重质量最多达到0.033 mg/cm²,其腐蚀动力学曲线遵循抛物线规律,而经过预氧化处理后合金表面腐蚀明显改善;合金在900 ℃下的热腐蚀符合硫化氧化模型,腐蚀产物出现了分层结构;合金的主要腐蚀产物是NiO、Al₂O₃以及少量NiCr₂O₄、TiO₂、NiS₂等, 其中Al₂O₃、TiO₂等氧化物位于氧化层最外层;预氧化生成的Al₂O₃层对高温合金在Na₂SO₄-NaCl盐膜下的短时热腐蚀有明显的保护作用,腐蚀层厚度从170 μm降低至80 μm.致密的氧化物保护层能够显著阻止硫元素的扩散,提高合金的耐热腐蚀性能.     

钴提取分离技术分析与应用

总结含钴废料处理过程中钴与镍、铁、铜、锰、铬、镉、钙镁、钼、钨、砷等元素的分离方法，并应用于处理某典型复杂含钴废料．产出纯度较高的草酸钴产品。     

克劳斯尾气加氢催化剂的器外硫化技术研究

研发了反应温度不同的两种固体硫化剂,并将该类硫化剂应用于克劳斯尾气加氢催化剂的硫化反应。对硫化剂的添加量、硫化过程中的操作条件进行了考察,通过能谱分析法确定活性组分的硫化率可达到硫化要求,通过催化剂性能评价确定催化剂可达到性能指标的要求,明确了提前硫化技术在克劳斯尾气加氢催化领域的可行性。     

长庆石化1.2Mt/a加氢裂化装置运行与标定

长庆石化1.2Mt/a加氢裂化装置选用壳牌标准催化剂公司的DN-3551/Z-503/Z-3723/Z-673组合催化剂,开工时利用DMDS干法硫化后未进行液氨钝化,一次开车成功,装置运行平稳,能够满足生产需求。但有些指标未达到设计要求,如氢耗较高、轻质产品占比较大等。标定期间,氢油比为959∶1(体积比),氢分压为10.25MPa,加氢精制反应器和裂化反应器的平均反应温度分别为390.6℃和398.9℃。标定结果显示,加氢精制反应器前后脱硫率为98.1%,脱氮率为97.6%;反应单程转化率为57.38%;轻质油收率为91.78%,尾油收率为7.52%。经核算,得出化学氢耗为2.16%(占原料油质量百分数);反应热为168.46MJ/t原料;装置单位能耗为31.158kg标油/t原料。装置运行主要存在两个瓶颈问题:一是原料为高干点且硫低氮高的单一减压蜡油馏分,反应系统循环气中硫化氢含量不足而氨含量高,存在需要补硫的问题;二是系统压力设计低,而且原料性质较差,造成催化剂选型困难和操作苛刻度较高。     

钼/活性炭渣油加氢催化剂的硫化

钼/活性炭催化剂是一种新型渣油加氢催化剂,其硫化效果直接决定着催化剂的活性和稳定性。实验考察了硫化条件对钼/活性炭催化剂（Mo/AC）硫化度的影响,运用X射线衍射（XRD）、X射线光电子能谱（XPS）、扫描电子显微镜（SEM）和透射电镜（TEM）等手段对硫化态催化剂进行了表征。结果表明,以二硫化碳为硫化剂,正十六烷为硫化介质,在硫化温度350 ℃,硫化时间3 h,氢气初压6 MPa条件下催化剂硫化度为85%,活性相MoS2堆垛结构为4～6层,晶片长度为6～10 nm,分布比较均匀,具有良好的加氢活性。