氧化镁对聚丙烯/聚氯乙烯脱氯行为的影响

对废旧塑料的回收利用是近年来人们一直关注和不断研究的一个重要课题。将废塑料热裂解为燃料油或单体被认为是最具前景的处理方法之一[1]。当含有PVC的废旧塑料裂解时产生氯化氢气体,严重腐蚀设备;同时也会产生含氯的有机化合物,从而使其裂解生成的液体作为燃料使用时会生成有     

废旧塑料回收利用技术的现状及发展趋势

本文详细综述了从３０年代到现在国内外废旧塑料再生利用技术发展的过程及近几年废塑料回收最新技术,对未来废旧塑料回收利用技术的发展趋势进行了预测     

碳化硅纳米材料的溶剂热合成

本文综述了溶剂热法制备一系列碳化硅纳米材料的研究,包括一维纳米线、纳米带、纳米棒、二维纳米片及空心球等;同时,碳源过量时可形成碳包覆碳化硅的复合材料。使用废塑料作为碳源合成了碳化硅纳米材料,为废塑料的回收再利用提供了新途径。通过使用碘、硫等添加剂,有效降低了合成温度,显示出溶剂热技术在制备碳化硅方面的独特优势。     

碳化硅纳米材料的溶剂热合成

本文综述了溶剂热法制备一系列碳化硅纳米材料的研究,包括一维纳米线、纳米带、纳米棒、二维纳米片及空心球等;同时,碳源过量时可形成碳包覆碳化硅的复合材料。使用废塑料作为碳源合成了碳化硅纳米材料,为废塑料的回收再利用提供了新途径。通过使用碘、硫等添加剂,有效降低了合成温度,显示出溶剂热技术在制备碳化硅方面的独特优势。     

基于高温化学转化的废旧锂离子电池资源化技术

鉴于废旧锂离子电池的环境危害性和资源化价值的双重属性,对其进行无害化处理并对其中的有价资源进行回收再利用具有十分重要的意义。目前电池资源化技术主要通过高温或常温条件下的化学转化实现。高温条件下,废旧锂离子电池中有价元素化学转化速率快、回收流程短、物料适应性强,易于实现工业应用,相关技术成为废旧锂离子电池资源化研究热点之一。本文基于物相化学转化方式的差异,系统分析了高温化学还原、熔盐化学焙烧以及短程材料再生等方法的物理化学机理、技术特征及研究现状,并对比了不同技术的优势和存在的问题。在此基础上,提出今后高温化学转化方法实现废旧锂离子电池资源化研究中需要考虑材料的短程清洁循环再生、深入研究其化学转化机理。基于绿色化学原理的工艺设计开发出低能耗、环境友好的资源化工艺路线,真正实现废旧锂离子电池的绿色处理和循环利用。     

废旧塑料回收利用的现状及发展趋势

本文详细综述了从３０年代到现在国内外废旧塑料再生利用技术发展的过程及近几年废塑料回收最新技术，对未来肇旧塑料回收利用的发展趋势进行了预测。     

白色污染

塑料作为一种新型合成材料,随着人口膨胀、城市发展、科技进步,在其产量和品种不断增多的同时。大量用过被丢弃的塑料制品所带来的“白色污染”,却越来越成为困扰人类社会的一大公害。本文较详细地讨论了塑料及其废弃物对人体及环境的危害以及废塑料的回收、利用、资源化、能源化和与之有关的分解性塑料等问题。     

废塑料裂解制液体燃料和化学品技术开发进展

本文对废塑料裂解制取液体燃料和化学品的最新进展进行了评述。讨论了典型工艺流程和存在的问题及解决办法。     

加热速率和粒径对聚乙烯在超临界水中转化的影响

随着塑料制品的广泛使用，废塑料在中国每年呈递增趋势，在城市垃圾中特别是沿海地区废塑料的质量分数己增加到8％～10％，而体积分数达到30％以上，造成严重的“白色污染”。回收利用废塑料不仅可以解决环境污染问题，而且可以将废弃物转化为资源。废塑料降解油化可以得到价值较高的液体燃料或化工原料，是一种较为理想的回收利用方法。     

二氧化碳的间接利用:碳酸乙烯酯应用研究进展

以二氧化碳(CO2)为主的温室气体排放所导致的全球气候和生态系统变异问题正得到普遍重视,全球CO2年排放量已达数百亿吨[1].控制CO2排放量,对其回收、固定、利用及再资源化,已成为世界各国严重关切的问题.同时,从资源化角度出发,CO2是世界上最为丰富和廉价的碳一(C1)资源[2,3],因此,大力发展二氧化碳的绿色化利用技术,开发绿色高新精细化工产业链,提高产品的附加值,具有重要的意义.     

Reductive amination of 1,6-hexanediol with Ru/Al_2O_3 catalyst in supercritical ammonia

Hexamethylenediamine(HMDA) is an important reagent for the synthesis of Nylon-6,6, and it is usually produced by the hydrogenation of adiponitrile using a toxic reagent of hydrocyanic acid. Herein, we developed an environmental friendly route to produce HMDA via catalytic reductive amination of 1,6-hexanediol(HDO) in the presence of hydrogen. The activities of several heterogeneous metal catalysts such as supported Ni, Co, Ru, Pt, Pd catalysts were screened for the present reaction in supercritical ammonia without any additives. Among the catalysts examined, Ru/Al_2O_3 presented a high catalytic activity and highest selectivity for the desired product of HMDA. The high performance of Ru/Al_2O_3 was discussed based on the Ru dispersion and the surface properties like the acid-basicity. In addition, the reaction parameters such as reaction temperature,time, H_2 and NH_3 pressure were examined, and the reaction processes were discussed in detail.     

Catalytic performance of iron oxide loaded on electron-rich surfaces of carbon nitride

Carbon nitride(CN) in CN encapsulated Ni/Al_2O_3(denoted as CN/Ni/Al_2O_3) catalyst was evidenced previously as a material in electron-rich state and possessed H2-dissociative adsorption activity due to the electron doping effect from underlying nickel. In this report, iron oxide loaded on the CN/Ni/Al_2O_3 was synthesized and investigated by Fischer-Tropsch(F-T) synthesis to test the special effect of electron-rich support on the catalytic activity of iron oxide. The Fe/CN/Al_2O_3 and CN/Ni/Al_2O_3 samples were accordingly synthesized for comparison. In Fe/CN/Ni/Al_2O_3, the iron oxide was reduced to magnetite by syngas as evidenced by the in-situ XPS measurements and XRD pattern of used catalyst. Compared with Fe/CN/Al_2O_3, more light hydrocarbons over Fe/CN/Ni/Al_2O_3 were observed. It should be understood by the interaction between iron oxide and support mainly due to the effect of electron-rich state and thus enhanced H_2 adsorption ability. In addition, such a novel support facilitated the CO conversion and retarded the water-gas shift reaction and CO2 formation. The new type of adjustment on electronic state should be useful for novel catalyst design.     

Effect of ethanedioic acid functionalization on Ni/Al_2O_3 catalytic hydrodeoxygenation and isomerization of octadec-9-enoic acid into biofuel: kinetics and Arrhenius parameters

The effect of ethanedioic acid(Ed A) functionalization on Al_2O_3 supported Ni catalyst was studied on the hydrodeoxygenation(HDO), isomerization, kinetics and Arrhenius parameters of octadec-9-enoic acid(OA) into biofuel in this report. This was achieved via synthesis of two catalysts; the first, nickel alumina catalyst(Ni/Al_2O_3) was via the incorporation of inorganic Ni precursor into Al_2O_3; the second was via the incorporation nickel oxalate(Ni Ox) prepared by functionalization of Ni with Ed A into Al_2O_3 to obtain organometallic Ni Ox/Al_2O_3 catalyst. Their characterization results showed that Ni species present in Ni/Al_2O_3 and Ni Ox/Al_2O_3 were 8.2% and 9.3%, respectively according to the energy dispersive X-ray result. Ni Ox/Al_2O_3 has comparably higher Ni content due to the Ed A functionalization which also increases its acidity and guarantees high Ni dispersion with weaker metal-support-interaction leading to highly reducible Ni as seen in the X-ray diffraction, X-ray photoelectron spectroscopy, TPR and Raman spectroscopy results. Their activities tested on the HDO of OA showed that Ni Ox/Al_2O_3 did not only display the best catalytic and reusability abilities, but it also possesses isomerization ability due to its increased acidity. The Ni Ox/Al_2O_3 also has the highest rate constants evaluated using pseudo-first-order kinetics,but the least activation energy of 176 k J/mol in the biofuel formation step compared to 244 k J/mol evaluated when using Ni/Al_2O_3. The result is promising for future feasibility studies toward commercialization of catalytic HDO of OA into useful biofuel using organometallic catalysts.     

负载型纳米ZrO_2/Al_2O_3复合载体的制备和表征及其Ni/ZrO_2/Al_2O_3催化性能的研究

以大孔Al2O3为基载体,采用沉积-沉淀法和溶胶-沉积法制备了负载型纳米ZrO2/Al2O3复合载体.用XRD、TEM和比表面与孔径测定等手段对载体进行了表征.结果表明,负载型纳米ZrO2/Al2O3复合载体具有较大的比表面积和适宜的孔径分布,纳米ZrO2在载体上呈单层均匀分布.以CH4-CO2重整制合成气为探针反应,考察了Ni/ZrO2/Al2O3催化剂的活性和选择性.     

准“原位”XPS技术研究加氢精制催化剂的硫化过程

用准“原位”XPS技术研究了Mo/Al_2O_3、Mo/TiO_2-Al_2O_3、CO/Al_2O_3、CO/TiO_2-Al_2O_3、Co-Mo-Al_2O_3和Co-Mo/TiO_2-Al_2O_3等催化剂的硫化过程．结果表明：对以Al_2O_3为载体的催化剂，当Mo或Co载量较低(分别低于0.05 gMoO_3/gAl_2O_3或0.03gCoO/gAl_2O_3)时，没有Mo或Co硫化物的生成，而以TiO_2改性的Al_2O_3为载体的催化剂，Mo/TiO_2-Al_2O_3催化剂的硫化较Mo/Al_2O_3容易得多, 表现为在较低温度下，负载在TiO_2改性Al_2O_3载体上的MoO_3，能很快硫化并达到相当大的硫化度, 对Co/Al_2O_3催化剂而言，即使在较高温度400 ℃时，载体上高分散的CoO物种仍难以硫化；而Co_3O_4微晶的硫化却容易得多, 载体用TiO_2改性，并不影响高分散形态的CoO催化剂的硫化，却明显地影响Co_3O_4微晶的硫化．噻吩加氢脱硫(HDS)的活性测量指出，对Co-Mo/Al_2O_3和Co-Mo/TiO_2-Al_2O_3催化剂而言，HDS活性和硫化度之间存在着良好的相关性．并用TiO_2改性载体，可以增加Co-Mo催化剂的HDS活性和硫化度.     

溶剂化金属原子浸渍法制备高分散载型催化剂 II. Fe,Co,Ni催化剂的分散度和催化性能研究

本文利用一种新的方法-溶剂化金属原子浸渍法制备了Fe/γ-Al_2O_3, Fe/SiO_2, Co/γ-Al_2O_3,Co/SiO_2, Ni/γ-Al_2O_3和Ni/SiO_2六种催化剂。H_2化学吸附, TEM和XRD测定结果表明这些催化剂中Fe, Co, Ni金属颗粒平均直径都小于3.0 nm, 金属分散度均大于50%。作者研究了Fe/γ-Al_2O_3, Co/γ-Al_2O_3和Ni/γ-Al_2O_3三种催化剂在CO+H_2反应中的催化行为, 测定了碳氢产物分布和比催化活性, 表明随着H_2/CO比增大和反应温度升高。较高分子量物种产量减少, 有利于生成甲烷。催化剂的活性大小次序为Fe>Ni>Co。     

钴、钌在加氢脱硫催化剂中的助剂作用

以CO, NO, H_2, O_2作为探针分子, 应用红外光谱法和化学吸附法研究了还原态Co-Mo/Al_2O_3, Ru-Mo/Al_2O_3和Ru-Co-Mo/Al_2O_3催化剂中Co, Ru的助剂作用。结果表明, Co担载在Mo/Al_2O_3上, 由于Co与Al_2O_3之间的相互作用减弱, Co中心上吸附CO和NO的能力增强, 改变了Mo中心吸附CO, NO, H_2,O_2的能力, 表现出Co-Mo/Al_2O_3上的Co中心性质显著地不同于Co/Al_2O_3。Ru担载在Mo/Al_2O_3或Co-Mo/Al_2O_3催化剂上, Ru自身的吸附CO, H_2, O_2能力降低, 但促进了MoO_3的还原, 使CO, NO, H_2, O_2在Mo中心上的吸附量增加。可以认为, Ru的作用是活化, 解离氢, 通过溢流氢促进配位不饱和的Mo中心生成。Ru的这种作用比Co明显。     

The effect of Al~(3+) coordination structure on the propane dehydrogenation activity of Pt/Ga/Al_2O_3 catalysts

The effect of the Al_2O_3 structure on the performance of Pt/Ga/Al_2O_3 catalysts is investigated for the direct dehydrogenation of propane. The study unveils that the structure of Al~(3+)determines the bulk structure of catalysts, particularly a high content of coordinatively unsaturated Al~(3+)sites(penta-coordinated Al~(3+),denoted as Al~(3+)penta) could lead to a remarkably improved dehydrogenation activity of the catalyst. The bulk characterization reveals that the sufficient amount of Al~(3+)pentain Al_2O_3 benefit the dispersion of Pt and Ga_2O_3 on the Al_2O_3 support. At the same time, TPR results reveal that the presence of Pt facilitates the reduction of Ga_2O_3, likely due to the hydrogen spillover between the well dispersed Pt and Ga_2O_3,which consequently enhances the synergistic function between Pt and Ga_2O_3 in the dehydrogenation of propane. Recyclability tests demonstrate that the dehydrogenation activity stabilizes after three cycles over the Pt/Ga/Al_2O_3 catalyst.     

单层分散型Pt/Ni双金属催化剂的制备及其C=C和C=O催化加氢性能

 利用金属置换反应制备了表面单层分散型Pt/Ni双金属催化剂,并测定了该催化剂对环己烯、苯乙烯、丙酮和丁醛气相加氢反应的催化性能. 结果发现,这种催化剂具有比传统浸渍法制备的相同Pt含量的Pt/Ni和Pt/Al2O3催化剂更高的催化活性.     

混合硝酸镍和醋酸镍制备的催化剂的特征和催化加氢抗硫性能

使用直接还原镍盐前体[Ni(NO_3)_2/γ-Al_2O_3, NiAc_2/γ-Al_2O_3或Ni (NO_3)_2-NiAc_2/γ-Al_2O_3]和镍氧化物前体的方法制备催化剂,研究了它们的 表面特征和甲苯加氢抗硫性能。还原镍盐得到的催化剂比还原其焙烧成的氧化物制 得的催化剂金属的还原和分散程度高。Ni(NO_3)_2-NiAc_2/γ-Al_2O_3分解得到的 氧化物前体的TPR在约415 ℃出现了较小数量的块状NiO的还原峰;而Ni(NO_3)_2- NiAc_2/γ-Al_2O_3的TPR中镍盐分解成氧化物时的耗氢量变小。用氢溢流的概念和 镍盐分解时的耗氢量可以将TPR的结果和金属的分散性关联起来。在镍盐前体催化 剂上甲苯的加氢具有较高的活性,而两种盐摩尔比为1：1时,盐前体催化剂反应活 性出现了一极大值,同时盐和氧化物前体催化剂都给出了抗硫性能的极大值。