吸附法净化制氨原料气技术方案的财务评价

采用吸附法净化制合成氨原料气,比传统的铜洗法有节约能源,物耗,降低生产成本。净化度高以及工艺简单等优点,通过对年产8万吨吸附法净化制氨原料气技术方案的财务评价,得出应大力推广该项新技术的结论。     

Recovery of platinum, tin and indium from spent catalysts in chloride medium using strong basic anion exchange resins

This work describes a route for platinum recovery from spent commercial Pt and PtSnIn/Al₂O₃ catalysts using strong basic mesoporous and macroporous anion exchange resins (Cl⁻ form). The catalysts were leached with aqua regia (75 °C, 20-25 min). Platinum adsorption was influenced by the presence of other metals which form chlorocomplexes (tin, indium) and also base metals (aluminum). However, it was possible to overcome this fact by a sequential desorption procedure. Aluminum was selectively removed from the resins by elution with 3 mol L⁻¹ HCl. Platinum was desorbed passing 1 mol L⁻¹ Na₂S₂O₃ (pH 9). Tin was removed by elution with 0.1 mol L⁻¹ ascorbic acid. Indium was removed using 0.1 mol L⁻¹ EDTA as eluent. Desorption efficiency exceeded 99% for all metals. Metals were recovered in high yields (>98 wt%).     

茶树菇水溶性多糖的分离纯化和化学组成的研究

本研究为了对茶树菇保健食品的研究开发提供理论依据,研究了茶树菇中的功能因子——真菌水溶性多糖。研究中首次分离纯化得到五种茶树菇水溶性多糖,并进一步分析研究其中含量最大的多糖AP2的物理化学组成。结果表明,AP2分子量为122460,是由D-葡萄糖、D-甘露糖、D-木糖和半乳糖醛酸组成的酸性多糖,其中半乳糖醛酸含量为6.8%。     

车用三元催化器故障诊断系统和实车检测装置的研究

作者在汽车的机外排放控制装置———三元催化器的失效原理的基础上 ,提出了汽车三元催化器故障诊断系统。该方案主要是检测发动机排气的参数和催化器的转化效率 ,通过这些特征参数诊断催化器故障。同时 ,对本系统采集的数据进行了分析 ,证实了该方法的可行性     

Extended Lifetimes of Gold(III) Chloride Catalysts using Copper(II) Chloride and 2,2,6,6‐Tetramethylpiperidine 1‐Oxyl (TEMPO)

The turnovers of a gold(III) chloride catalyst were increased by 3,300% with the addition of several equivalents of 2,2,6,6‐tetramethylpiperidine 1‐oxyl (TEMPO) and catalytic amounts of copper(II) chloride. A three‐component coupling reaction between piperidine, phenylacetylene, and benzaldehyde yielded a propargylic amine in quantitative conversions and isolated yields when gold(III) chloride was added in catalytic amounts, but the gold catalyst decomposed and had little to no reactivity when a second set of piperidine, phenylacetylene, and benzaldehyde was added after the reaction was complete. Thus, only one cycle was possible with gold(III) chloride. The addition of TEMPO and copper(II) chloride to reactions with gold(III) chloride maintained the catalytic activity of gold for up to 33 cycles. This result demonstrates a new way to greatly increase the turnovers of a gold(III) chloride catalyst with the addition of inexpensive, commercially available reagents.     

紫芝胞外多糖分离纯化及抗氧化性的研究

目的:探讨紫芝（Ganoderma Sinense）胞外多糖的分离纯化及抗氧化活性。方法:采用乙醇沉淀法、聚酰胺脱蛋白法,DEAE-52阴离子交换色谱柱法分离纯化紫芝胞外多糖;通过对DPPH自由基、超氧阴离子自由基和羟自由基的清除能力的测定确定抗氧化活性。结果:粗多糖经DEAE-52柱层析纯化得到三种多糖组分GSP1、GSP2和GSP3,均具有抗氧化活性。其中GSP2的抗氧化活性尤为明显,在1.6mg/mL时DPPH自由基清除率达到76.3%;在5mg/mL时羟自由基的清除率达到81.5%。结论:三种紫芝胞外多糖组分具有较强的抗氧化活性,其中GSP2最为明显。      

Preparation of a modified crosslinked chitosan/polyvinyl alcohol blended affinity membrane for purification of His-tagged protein

Based on a crosslinked chitosan (CS)/polyvinyl alcohol (PVA) matrix membrane, an immobilized metal ion affinity membrane (IMAM) using Cu²⁺ and Ni²⁺ ions as affinity ligands was prepared for purification of the His-tagged recombinant protein. The affinity membrane possessed a favorable membrane structure including 1.39 μm average pore size and 0.33 mL·cm⁻²·s⁻¹ water flux under 0.08 MPa pressure at 25 °C. The Cu²⁺ and Ni²⁺ ions capacities immobilized on the IMAM were 155.6 and 137.3 μmol·disk⁻¹, respectively. The IMAM had an excellent specific affinity to His-tagged protein. About 10-fold purification factor for the model protein was obtained in a batch adsorption, and serine hydroxymethyl transferase could be purified to a single band in sodium dodecyl sulfate–polyacrylamide gel electrophoresis analysis from its crude extract solution with an affinity membrane cartridge by a dynamic purification process. This work provides a promising IMAM for the purification of His-tagged recombinant proteins. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47347.     

Unusual selectivity of oxygenate synthesis: Formation of acetic acid from syngas over unpromoted Rh in NaY zeolite

Syngas conversion over Rh/zeolite-NaY catalysts at high-pressure lead to high yields of acetic acid. This unusual selectivity toward one oxygenate in the absence of any catalyst promoter is most pronounced at lower temperature; the apparent activation energy for overall CO-hydrogenation is 23.7 kcal/mol, but for the formation of acetic acid it is 11.9 kcal/mol. The selectivity is little affected by the protons formed during the reduction of Rh. In stiu FT-IR measurement reveals that changes in activity and selectivity during the start-up period are caused by thorough catalyst reconstruction, converting the original Rh⁰ clusters to multinuclear Rh₆(CO)₁₆ and CH₃Rh_y(CO)_x and/or mononuclear CH₃Rh(CO)_x carbonyl complexes, and smaller Rh⁰ clusters. Stable acetate groups, but not the surface bound acetyls, are formed and detected by FT-IR. Most of the cooperating Rh species survive when the pressure is lowered from 1.0 to 0.1 MPa, maintaining a high acetic acid selectivity that is vastly superior to that of the fresh catalyst.     

Acid-catalyzed moisture-curing polyurea/polysiloxane ceramer coatings

The para-toluene sulfonic acid (p-TSA) was used to catalyze the moisture curing of an organic/inorganic hybrid coating system. The organic phase was based on the isocyanurate of 1,6-hexamethylene of diisocyanate (HDI). The inorganic phase was based on the prepolymerized oligomers of tetraethyl orthosilicate (TEOS). An alkoxysilane-functionalized HDI isocyanate was added into the coating formulation to aid in phase miscibility. The general coating and tensile properties were evaluated as a function of the acid catalyst concentration. In addition, the films were analyzed using differential scanning calorimetry (DSC) and dynamical mechanical thermal analysis (DMTA). The results indicated that the acid catalyst enhanced the adhesive properties of the hybrid coatings. The addition of the acid catalyst increased the changed crosslink density of films and decreased the crystallinity of the organic phase.     

热分析技术在催化研究中的应用

介绍了热分析技术在研究催经剂的物相变化,制备条件,活性相变化,失活的分解温度等方面的应用。