Visbreaking of heavy petroleum oil catalyzed by SO42-/ZrO2 solid super-acid doped with Ni2+ or Sn2+

SO₄²⁻/ZrO₂ solid super-acid catalysts (SZ) doped with Ni²⁺ or Sn²⁺ (Ni²⁺/SZ, Sn²⁺/SZ) were prepared for catalytic visbreaking of heavy petroleum oil from Shengli oil field. The visbreaking reactions were carried out at 240°C and 3–4 MPa for 24 h using a heavy petroleum oil to catalyst mass ratio of 100 : 0.05. The effect of water content on viscosity of heavy petroleum oil was also investigated. Both catalysts can promote thermolysis of heavy petroleum oil and the viscosity was reduced from 0.319 Pa·s to 0.135 Pa·s for Ni²⁺/SZ and 0.163 Pa·s for (Sn²⁺/SZ) with visbreaking rates of 57.7% and 48.9%, respectively. After visbreaking, the saturated hydrocarbon content increased while aromatics, resin, asphaltene, sulfur and nitrogen content decreased. The presence of water was disadvantageous to visbreaking of heavy petroleum oil. __________ Translated from Petrochemical Technology, 2007, 36(3): 237–241 [译自: 石油化工]     

金属离子催化葡萄糖异构化和脱水反应特性研究

以金属氯化物为催化剂,研究金属离子对葡萄糖异构化和脱水反应的催化特性。考察金属离子种类、用量和温度对反应过程的影响,用动力学模型拟合实验数据,定量分析金属离子的催化规律。葡萄糖脱水制备HMF的反应是一个串联反应,基于此机理构建的动力学模型能准确描述各组分浓度随时间的变化。Ni²⁺、Cr³⁺和Sn⁴⁺具有良好的催化活性,但3种金属离子呈现不同的催化特性。Sn⁴⁺的葡萄糖转化速率最快,Ni²⁺最慢,但Sn⁴⁺的副反应速率常数是Ni²⁺的约20倍。实验范围内,增加Ni²⁺用量,葡萄糖异构化和副反应速率加快,但对果糖脱水过程没有催化活性。增加Cr³⁺用量能显著提升葡萄糖异构化速率,对其它反应影响不大。随着Sn⁴⁺用量的增大,各步反应速率均加快,但整个反应过程中的副反应的严重程度有所降低。反应速率常数随温度的变化规律遵循Arrhenius模型,对Ni²⁺而言...     

稠油注空气催化氧化采油催化剂的制备与评价

注空气催化氧化采油技术是一项提高稠油采收率的创新技术,因其气源丰富、成本低,越来越受到人们关注。该文针对SZ36-1稠油,制备了5种油溶性催化氧化催化剂——过渡金属环烷酸盐,并加以筛选,得到环烷酸铜催化效果最佳。对稠油注空气催化氧化条件进行了初步评价。在催化剂用量为原油质量的0.2%,反应温度100℃,反应时间3 d的条件下,稠油酸值从3.96 mg KOH/g上升至13.50 mg KOH/g,黏度由2.004 Pa.s上升到11.48 Pa.s,尾气中φ(O2)由21.0%降至10.0%。向氧化油中分别加入氧化油质量1.2%的助剂SW-1和质量分数40%的水,保温50℃搅拌,生成大量表面活性剂,形成O/W乳化油,黏度最终降至0.067 Pa.s,总降黏率达到96.66%。     

In situ XPS investigations of Cu1−xNixZnAl-mixed metal oxide catalysts used in the oxidative steam reforming of bio-ethanol

A series of CuNiZnAl-multicomponent mixed metal oxide catalysts with various Cu/Ni ratios were prepared by the thermal decomposition of Cu_1−xNi_xZnAl-hydrotalcite-like precursors and tested for oxidative steam reforming of bio-ethanol. Dehydrogenation of EtOH to CH₃CHO is favored by Cu-rich catalyst. Introduction of Ni leads to CC bond rupture and producing CO, CO₂ and CH₄. H₂ yield (selectivity) varied between 2.6–3.0 mol/mol of ethanol converted (50–55%) for all catalysts at 300 °C. The above catalysts were subjected to in situ XPS studies to understand the nature of active species involved in the catalytic reaction. Core level and valence band XPS as well as Auger electron spectroscopy revealed the existence of Cu²⁺, Ni²⁺ and Zn²⁺ ions on calcined materials. Upon in situ reduction at reactions temperatures, the Cu²⁺ was fully reduced to Cu⁰, while Ni²⁺ and Zn²⁺ were partially reduced to Ni⁰ and Zn⁰, respectively. On reduction, the nature of ZnO on Cu-rich catalyst changes from crystalline to amorphous, relatively inert and highly stabilized electronically. Relative concentration of the Ni⁰ and Zn⁰ increases upon reduction with decreasing Cu-content. Valence band results demonstrated that the overlap between 3d bands of Cu and Ni was marginal on calcined materials, and no overlap due to metallic clusters formation after reduction. Nonetheless, the density of states at Fermi level increases dramatically for Ni-rich catalysts and likely this influences the product selectivity.     

Protein-derived nitrogen and sulfur co-doped carbon for efficient adsorptive removal of heavy metals

A nitrogen and sulfur co-doped carbon has been synthesized employing egg white as a sustainable protein-rich precursor. According to CHNS elemental analysis, N, S and O heteroatoms accounted for mass fractions of 3.66%, 2.28% and 19.29% respectively, and the types of surface functionalities were further characterized by FT-IR and XPS measurements. Although the carbon possessed a smaller surface area (815 m²·g^-1) compared to a commercial activated carbon (1100 m²·g^-1), its adsorption capacity towards Co²⁺ reached 320.3 mg·g^-1, which was over 8 times higher compared to the limited 34.0 mg·g^-1 over the activate carbon. Furthermore, the carbon was found to be an efficient adsorbent towards a series of metal ions including VO²⁺, Cr³⁺, Ni²⁺, Cu²⁺ and Cd²⁺. Combined with its environmental merits, the protein derived carbon may be a promising candidate for heavy metal pollution control.     

Stellerite-seeded facile synthesis of zeolite X with excellent aqueous Cd2+ and Ni2+ adsorption performance

Zeolite X was synthesized by a two-step hydrothermal method using natural stellerite zeolite as the silicon seed, and its adsorption performance for Cd²⁺ and Ni²⁺ ions was experimentally and comprehensively investigated. The effects of pH, zeolite X dosage, contact time, and temperature on adsorption performance for Cd²⁺ and Ni²⁺ ions over were studied. The adsorption process was endothermic and spontaneous, and followed the pseudo-second-order kinetic and the Langmuir isotherm models. The maximum adsorption capacitiesfor Cd²⁺ and Ni²⁺ ions at 298 K were 173.553 and 75.897 mg·g^-1, respectively. Ion exchange and precipitation were the principal mechanisms for the removal of Cd²⁺ ions from aqueous solutions by zeolite X, followed by electrostatic adsorption. Ion exchange was the principal mechanisms for the removal of Ni²⁺ ions from aqueous solutions by zeolite X, followed by electrostatic adsorption and precipitation. The zeolite X converted from stellerite zeolite has a low n(Si/Al), abundant hydroxyl groups, and high crystallinity and purity, imparting a good adsorption performance for Cd²⁺ and Ni²⁺ ions. This study suggests that zeolite X converted from stellerite zeolite could be a useful environmentally-friendly and effective tool for the removal of Cd²⁺ and Ni²⁺ ions from aqueous solutions.     

阳离子交换树脂改性研究进展

强酸性阳离子交换树脂含有大量的强酸性基团,具有选择、交换、吸收和催化等功能,但其存在耐高温性能差、酸强度低等问题,故需要对其进行改性。改性的阳离子交换树脂广泛应用于水处理、有机合成、分离处理、环境保护及生物制药等领域。本文简要介绍了近年来强酸性阳离子交换树脂的改性方法,主要包含:金属离子改性(Al³⁺、Sn⁴⁺、Zn²⁺、Ti⁴⁺、Fe³⁺和Fe²⁺、Ce⁴⁺和Ga³⁺、Ni²⁺、Zr⁴⁺、Pd²⁺等)、磺化改性、巯基改性、胺化改性及其他类改性等方法;指出了其存在的问题,分析了改性阳离子交换树脂的未来发展方向,开发和研制具有耐高热和化学稳定性的树脂载体材料成为其研究的关键。除此之外,对树脂进行各种改性处理也是改善树脂综合性能、扩大其应用范围的重要方法。     

［(MoO2)(acac)2］/t-BuOOH/H3PO4催化氧化体系对稠油中重组分的降解作用

针对稠油的重组分，探讨了催化氧化稠油降解反应体系中稠油黏度、平均分子量随反应时间、催化剂及氧化降解体系的变化规律.研究了各种条件下油层矿物在反应中的作用.实验结果表明，［(MoO₂)(acac)₂］催化剂对稠油的氧化降黏是非常有效的，其催化降解反应与氧化剂、氢质子供体以及油层矿物有关.在［(MoO₂)(acac)₂］/t-BuOOH/H₃PO₄/油层矿物体系中，稠油沥青质降解率达到81%，稠油黏度由原始的117.2 Pa·s下降到55.8 Pa·s，下降率为52.4%，平均相对分子质量下降了100.TLC-FID分析证明，稠油中的沥青质减少主要生成胶质、芳烃和饱和烃，这种理化性质的改变促进了稠油体系的稳定，对稠油开采、运输以及后处理工艺将起到推动作用.     

Nickel(II) ion-intercalated MXene membranes for enhanced H2/CO2 separation

Hydrogen fuel has been embraced as a potential long-term solution to the growing demand for clean energy. A membrane-assisted separation is promising in producing high-purity H₂. Molecular sieving membranes (MSMs) are endowed with high gas selectivity and permeability because their well-defined micropores can facilitate molecular exclusion, diffusion, and adsorption. In this work, MXene nanosheets intercalated with Ni²⁺ were assembled to form an MSM supported on Al₂O₃ hollow fiber via a vacuum-assisted filtration and drying process. The prepared membranes showed excellent H₂/CO₂ mixture separation performance at room temperature. Separation factor reached 615 with a hydrogen permeance of 8.35 × 10⁻⁸ mol·m⁻²·s⁻¹·Pa⁻¹. Compared with the original Ti₃C₂T_x/Al₂O₃ hollow fiber membranes, the permeation of hydrogen through the Ni²⁺-Ti₃C₂T_x/Al₂O₃ membrane was considerably increased, stemming from the strong interaction between the negatively charged MXene nanosheets and Ni²⁺. The interlayer spacing of MSMs was tuned by Ni²⁺. During 200-hour testing, the resultant membrane maintained an excellent gas separation without any substantial performance decline. Our results indicate that the Ni²⁺ tailored Ti₃C₂T_x/Al₂O₃ hollow fiber membranes can inspire promising industrial applications.     

麦羟基硅钠石的可控合成及其阳离子交换性能研究

目前,开发绿色高效的重金属吸附材料受到人们的广泛关注。以硅藻土为原料,经水热法选择性地制备了2类硅酸盐材料即麦羟基硅钠石和方沸石。吸附测试结果表明,麦羟基硅钠石层间的钠离子能够与锂离子、镁离子、锌离子、钴离子、镍离子、铜离子等进行阳离子交换且能保持层状母体框架的稳定性。以钴离子、镍离子为例深入研究其吸附动力学和吸附机制发现,钴离子和镍离子的嵌入分别将麦羟基硅钠石的层间距由本征的1.56 nm减小到0.24、0.23 nm;室温下,对钴离子、镍离子的最大吸附量分别可达45、39 mg/g,均符合Langmuir单层吸附模型;钠离子的置换量大约是吸附的钴离子、镍离子量的两倍,证实层间离子交换主导吸附化学过程。因此,麦羟基硅钠石材料在多金属硅酸盐功能材料的合成以及环境吸附净化领域具有较大的应用潜力。     

A Simple Model for Predicting the Two-Phase Heavy Crude Oil Horizontal Flow with Low Gas Fraction

A two-phase heavy crude oil flow with low gas fraction is common in the oil transportation process. However, most of the studies of a gas–liquid flow are based on low viscosity fluid, such as water and light oil; as a result, the results cannot be introduced successfully into the mixture flow of gas and heavy crude oil. In this work, a two-phase flow of gas and heavy crude oil, which originated from the Bo-hai oilfield in China, was investigated in a horizontal pipe with 47-mm inner diameter. Data were acquired for the oil flow rate ranging from 2 m³/h to 10 m³/h, the input gas volume fraction ranging from 0.01 to 0.15, and the viscosity of crude oil ranging from 2.41 Pa·s to 0.34 Pa · s. Based on the drift-flux model, a new simplified correlation was developed to predict the void fraction and the pressure gradient. A comparison between the predicted and measured data demonstrates a reasonable agreement, and the correlation might be helpful for practical application in industry, especially in initially estimating the flow characteristic parameters.     

Catalytic oxidation of sulfide ions over nickel hydroxides

The catalytic sulfide ion oxidation by oxygen to elemental sulfur over β-Ni(OH)₂ and LiNiO₂ has been studied. As a result of experimental investigation performed, a reaction mechanism is suggested which involves heterogeneous and homogeneous processes. Dioxygen activation in the heterogeneous process proceeds via a redox Ni²⁺ ↔ Ni³⁺ transition and participation of OH⁻ groups. The active HO⁻₂ species thus formed carries on the reaction in homogeneous phase. Nickel hydroxides are promising catalysts for practical application.     

陶瓷膜短流程工艺处理重金属废水

针对电镀行业重金属废水常规处理方法存在的药剂投加量大、污泥产量多、水质波动影响大等不足,本文提出了一种新工艺-陶瓷膜短流程处理工艺,即废水通过调节pH值使重金属离子形成相应的氢氧化物絮体后,直接进入陶瓷膜组件过滤,同时辅以曝气缓解膜污染。通过实验室小试研究了pH值、重金属质量浓度和曝气量等因素对重金属(Cu²⁺、Cr³⁺和Ni²⁺)去除效果以及陶瓷膜跨膜压差的影响,并进行现场中试验证。试验结果表明:pH=10时,Cu²⁺、Cr³⁺和Ni²⁺的去除率分别达到99.8%、99.7%和99.9%,耐冲击负荷强,原水重金属离子质量浓度为500mg/L时出水也能满足要求。气水体积比值为15时,能在保证出水水质的前提下显著缓解膜污染。该工艺中陶瓷膜的污染主要为可逆污染,可以通过水力反冲洗去除。在pH=10、气水体积比值为15和膜通量为80L/(m²·h)时,现场中试工艺出水中Cu²⁺、Cr³⁺和Ni²⁺的质量浓度分别低于0.15mg/L、0.3mg/L和0.1mg/L,而且跨膜压差保持稳定。     

不同变质程度超微煤粉对重金属离子的吸附性能

重金属离子由于具有毒性、难以生物降解且可在生物体内累积,严重威胁人类的身体健康。吸附是去除重金属离子的一种可行有效的方法。本文选择褐煤、烟煤、无烟煤3种变质程度不同的煤种,通过高能球磨获得超微煤粉。研究了3种超微煤粉对水溶液中Ni²⁺和Cr⁶⁺的吸附动力学与热力学以及投加量与pH值对吸附效果的影响。结果表明3种煤粉对Ni²⁺、Cr⁶⁺的吸附量均随时间的增加而增加,并且Ni²⁺的处理效果明显好于Cr⁶⁺,在180min时褐煤、无烟煤与烟煤对Ni²⁺、Cr⁶⁺的吸附量分别为3.906mg/g、3.582mg/g、2.983mg/g和1.953mg/g、1.774mg/g、0.487mg/g。3种煤粉对两种重金属离子的吸附均符合二级吸附动力学和Freundlich等温式,随着投加量与pH值的增加,去除效果增加,在相同条件下,褐煤的吸附效果优于烟煤与无烟煤。     

NO reduction by CH4 in the presence of excess O2 over Pd/sulfated zirconia catalysts

The selective catalytic reduction (SCR) of NO by methane in the presence of excess oxygen has been studied on a series of Pd catalysts supported on sulfated zirconia (SZ). This support is not as sensitive to structural damage by steaming as the acidic zeolites, such as H-ZSM-5 and H-Mor. In previous studies, it was shown that this type of acidic zeolites are able to stabilize Pd²⁺ ions and promote high SCR activity and selectivity, which are typically not seen in Pd catalysts. In this contribution, it has been demonstrated that SZ is able to promote the NO reduction activity in a similar way to the acidic zeolites, by stabilizing Pd²⁺ ions that is selective for NO reduction. As in the case of acidic zeolites, the stabilization of Pd²⁺ ions can occur through a transfer of Pd species from particle to particle. One of the attractive features of Pd/SZ catalysts is that they are less sensitive to water and SO₂ poisoning than Pd/H-ZSM-5 catalyst and exhibit higher reversibility after removal of water or SO₂.     

国外渣油加氢技术研究进展

随着原油劣质化趋势的加剧及环保法规的日益严格,渣油加氢技术已成为炼厂提高轻油收率的关键技术。本文针对目前主要的渣油加氢技术,比较了固定床、沸腾床、悬浮床、移动床四大类型渣油加氢技术的优势和不足,重点分析了国外主要的渣油加氢技术的研究进展,探讨了未来的发展趋势。固定床加氢技术最成熟,在可预见的未来仍将占据渣油加氢的主导地位;沸腾床加氢技术日趋成熟,代表未来渣油加氢的发展方向;移动床加氢技术暂不作为渣油加氢的有效手段;悬浮床加氢技术尚未实现工业化应用,正在建设多套工业装置,具有良好的发展前景。渣油加氢技术与其他重油加工工艺进行优化集成,将会显著提高炼厂的经济效益。     

新型多胺羧甲基壳聚糖的合成及对Ni(Ⅱ)的吸附特性

为了提高壳聚糖(CS)吸附重金属的能力,对表面含有氨基乙酸基团的新型多胺羧甲基壳聚糖(CTGCS)进行了合成研究。其合成过程为:以CS为原料,通过戊二醛交联得到壳聚糖树脂(GCS),再经四乙烯五胺改性,得到多胺壳聚糖树脂(TGCS),最后采用一氯乙酸进行修饰,得到了目标产物(CTGCS)。通过对CS、GCS、TGCS和CTGCS进行红外光谱和XPS分析,对合成过程进行了分析。吸附结果表明,CTGCS对Ni²⁺的吸附规律符合Freundlich 等温式模型,吸附过程符合拟二级动力学模型,最大平衡吸附量为533.8 mg·g^-1,比TGCS的吸附量增加了1.5倍。     

钢渣对Ni2+与Cu2+的竞争吸附研究

将转炉钢渣磨碎筛分,从钢渣投加量、吸附时间、酸性条件等方面探究其对水溶液中Ni²⁺的吸附性能及吸附机理,并讨论Cu²⁺对钢渣吸附Ni²⁺的影响。研究结果表明,100 mL浓度为50 mg·L^-1的Ni²⁺溶液,用200目(0.074 mm)0.15 g的钢渣处理30 min,Ni²⁺的吸附率为99.88%。钢渣吸附Ni²⁺的过程符合准二级动力学模型和Freundlich等温模型。钢渣吸附Cu²⁺与吸附Ni²⁺属于竞争吸附,且钢渣对Cu²⁺的吸附能力优于对Ni²⁺的吸附能力。钢渣吸附Ni²⁺的过程以化学吸附为主,伴随着物理吸附,且随着钢渣表层吸附位点的减少,钢渣对Ni²⁺的物理吸附作用会逐渐减弱。该研究对处理工业含Ni²⁺与Cu²⁺的废水具有一定的指导意义。     

硫代杯[4]冠-4在硝酸体系中对Sr2+的萃取

乏燃料后处理的高放废液分离过程中,发展新型分离材料实现对锶的高效萃取至关重要。合成了1,2交替构象的硫代杯[4]冠-4(TCACE),利用FT-IR、¹H NMR和MS对目标产物进行了表征。研究不同稀释剂对萃取的影响,优化得出CH₂Cl₂为稀释剂,在硝酸浓度为3 mol·L^-1,有机相中硫代杯[4]冠-4浓度为1×10^-3 mol·L^-1,水相中Sr²⁺浓度为5×10^-4 mol·L^-1,萃取温度为25℃,萃取80 min条件下,平均传质系数为1.36×10^{-5 m}·s^-1,Sr²⁺的分配比为0.69。分析了不同条件对硫代杯[4]冠-4对Sr²⁺的萃取影响,研究了萃取计量方程式,实验结果表明萃合物为{Sr(NO₃)₂}·{TCACE}。研究了TCACE对其他金属离子Mo⁶⁺、Ni²⁺、Ag⁺、Sn⁴⁺等的萃取效果,表明对Sr²⁺具有较好的选择性。     

Ion-imprinted silica gel and its dynamic membrane for nickel ion removal from wastewaters

An ion-imprinted sorbent (IIP) was prepared by using Ni²⁺ as template, 3-[2-(2-aminoethylamino) ethylamino] propyl-trimethoxysilane as functional monomer, and silica gel as carrier. The adsorption performance of IIP towards Ni²⁺ was investigated. IIP showed a higher adsorption capacity than that of non-imprinted sorbent, and it also exhibited high selectivity for Ni²⁺ in the presence of Cu²⁺ and Zn²⁺ ions. Then, IIP was used to form a dynamic membrane onto the surface of ceramic membrane for treatment of electroplating wastewater containing Ni²⁺. Compared with ceramic membrane, IIP dynamic membrane had much higher steady membrane flux, and also rejected Ni²⁺ to obtain a lower concentration of Ni²⁺ in the permeate fluid. Perhaps it is suitable for future practice applications.