Regeneration of spent nickel catalyst from hydrogenation process of edible oils: Heat treatment with hydrogen injection

In this paper spent nickel catalyst (Ni/diatomite) resulting from hydrogenation process of edible oil was regenerated. To reach this aim heat treatments with hydrogen flushing was employed. The impact of particle size, reaction time and temperature on spent nickel catalyst regeneration were studied. The structural characteristics, elemental and chemical analysis of the samples were studied by Fourier transform infrared spectroscopy and X-ray fluorescence. The regenerated catalyst and fresh catalyst were tested in an experimental hydrogenation process. Noticeable regeneration achieved as under; mesh number: 200, time: 1 h and temperature: 450 °C. All Results showed that spent nickel catalyst could be regenerated directly. Through this method no part of the spent nickel catalyst was left in the environment and no reagent was used.     

Dry reforming of methane over Ni/dendritic fibrous SBA-15 (Ni/DFSBA-15): Optimization,mechanism, and regeneration studies

Dendritic fibrous type SBA-15 (DFSBA-15) was recently discovered with its outstanding catalytic performance and coke resistance as compared to the conventional SBA-15. The operating conditions for dry reforming of methane (DRM) over 10Ni/DFSAB-15 were optimized by using response surface methodology (RSM), followed by stability and regeneration study. Characterization results (TEM and FESEM) confirmed the homogenous distribution of NiO particles with no morphological change in spherical DFSBA-15 upon Ni addition. Process parameters, such as reaction temperature (X₁, 700 °C–900 °C), gas hourly space velocity (X₂, 15,000 mL/g.h ‒ 35,000 mL/g.h), and CH₄/CO₂ ratio (X₃, 1–3) were studied over CO₂ conversion (Y₁), CH₄ conversion (Y₂), and H₂/CO ratio (Y₃). The optimal reaction conditions were found at X₁ = 794.37 °C, X₂ = 23,815.022 mL/g.h, and X₃ = 1.199, with Y₁ = 95.67%, Y₂ = 93.48%, and Y₃ = 0.983. The in-situ FTIR studies of adsorbed CH₄, CO₂, and CH₄ + CO₂ confirmed the formation of unidentate carbonate, bidentate carbonate, and linear carbonyl species as intermediate species. 10Ni/DFSBA-15 presented good reproducibility by using both regeneration medium (air and CO₂/N₂) with two-fold regeneration by air as compared to CO₂/N₂. It was proven that the synthesized 10Ni/DFSBA-15 was appreciably stable and prone to be regenerated by air for DRM under optimal conditions.     

西藏民居类古建筑更新与利用 — —以邦达仓为例

古建筑作为城市文化的基本载体, 是城市文化复兴的重要场所。古建筑的更新方 式和利用形式多种多样,其更新利用一直是古 建筑保护研究的一个重要方向。为实现西藏 城市、建筑文化的复兴,充分发扬和利用绚丽 多样的地域特色文化遗产,通过对西藏古建 筑邦达仓的更新改造与利用情况进行深入调 研,对各阶段使用情况进行对比研究,总结出 西藏地区古建筑尤其是民居类古建筑在更新 利用过程中所存在的问题并针对性地提出建 议,为西藏古建筑更新提供参考。     

Regeneration of AgXO@SBA-15 for reactive adsorptive desulfurization of fuel

Adsorbent regeneration is critical for a continuous adsorption–regeneration process and often underestimated. In this work,the regeneration of bifunctional AgXO@SBA-15 for [O]-induced reactive adsorptive desulfurization of liquid fuel is reported and further investigated. The spent AgXO@SBA-15 was regenerated in various types of solvents followed by calcination and tested in multiple desulfurization–regeneration cycles. The effects of regenerate solvents were also compared systematically. The original and regenerated AgXO@SBA-15 was characterized by X-ray diffraction, transmission electron microscopy, energy-dispersive X-ray spectroscopy, N_2 adsorption, X-ray photoelectron spectroscopy and atomic absorption spectrometry. The recovery of desulfurization capacity using various solvents follows the order of acetonitrile [ acetone [ ethanol [ methanol [ water. Owing to the complete reduction of silver species to Ag~0 and severe agglomeration of Ag~0, the bifunctional AgXO@SBA-15 demonstrating [ 85%(2.60 mg-S/g) of sulfur removal dramatically reduced to \ 46%(1.56 mg-S/g) after only 1 st-cycle regeneration. It is suggested that polar organic species strongly adsorbed(or residual) on the spent AgXO@SBA-15, in that case, after solvent wash may contribute to the accelerated decomposition of Ag~+ to Ag~0 in the following calcination step. The desulfurization capacity decreased rather mildly in the later regeneration runs. Cautious choice of regeneration conditions and strategies to rational design stabilized adsorbents is required to avert the adsorbent deactivation.     

Feedback Architecture

The specialist research and design unit in Aedas' London office focuses on three principal areas of research: computational design, advanced modelling and sustainable design. Christian Derix, Judit Kimpian, Abdulmajid Karanouh and Josh Mason of Aedas R&D explain how this cross-pollination of interests has led the practice to develop innovative approaches, exemplified by the design for Al Bahr Towers, the Abu Dhabi Investment Council Headquarters and the Digital Masterplanning (Digma) tool. Copyright © 2011 John Wiley & Sons, Ltd.     

Theoretical and experimental investigation on the application of solar water heater coupled with air humidifier for regeneration of liquid desiccant

Theoretical and experimental investigation on the application of flat plate solar water heater coupled with air humidifier for regeneration of liquid desiccant has been presented in this work. The heated water from the storage tank of the solar heating system is circulated in a finned tube air heater. Hot air from the air heater is blown through a packing of a honeycomb type for the purpose of regeneration of calcium chloride (CaCl₂) solution. An experimental system has been designed and installed for this purpose. The system comprises a solar water heater with a storage tank connected to an air/water heat exchanger. Hot air from the heat exchanger is blown to the air humidifier, which functions in this study as a regenerator. Calcium chloride solution is applied as the working desiccant in this study. Solution concentration is determined at the end of regeneration process and the mass of evaporated water is evaluated. It is observed that the heating temperature varies, at day time, in a range of about 5 °C. This limited variation in hot water temperature demonstrates the importance of the storage tank to attain a nearly steady state operation of the system. Experimental results show that solution with 30% concentration can be regenerated up to 50% using solar energy. In the theoretical part of this study, a multiple-layer artificial neural network (ANN) model has been applied to study the performance of a solar liquid-desiccant dehumidification/regeneration system when calcium chloride solution is applied as the working desiccant. The experimental results of the present study are used to construct and test the ANN model. Then the model has been utilized to describe and analyze the effect of the inlet conditions of air on the regeneration process. Good agreement between the outputs from the ANN model and the corresponding results from the experimental data has been found. The proposed model can work well as a predictive tool to complement the experiments.     

The energy-saving characteristic of silica gel regeneration with high-intensity ultrasound

The energy-saving characteristic of silica gel regeneration with power ultrasonic was analyzed by introducing the conception of specific energy consumption. For the purpose, the experiments of silica gel regeneration with 21-kHz power ultrasound were performed under different drying air temperatures (i.e., 35, 45, 55 and 65 °C) combined with different acoustic power levels (i.e., 0, 20, 40 and 60 W). And the energy saving ratios of the ultrasonic-assisted regeneration were studied by the method of ANOVA (Analysis of Variance) and compared among different conditions. The influences of acoustic power and drying air temperature as well as the target moisture ratio (at which the regeneration process ended) on the total specific energy consumption (TSEC) and the excess specific energy consumption (ESEC) were also discussed. The results indicate that all the factors (drying temperature, ultrasonic power level and the interaction between the drying temperature and the power level) have a significant (P < 0.05) influence on the energy saving ratio, among which the influence of drying temperature is the most significant (P < 0.05). According to the analysis of specific energy consumption, the optimal drying conditions aiming at the minimum energy use can be obtained. For the present experimental conditions, the condition of 55 °C (drying temperature) and 60 W (acoustic power level) can achieve the lowest TSEC and ESEC. In addition, different thresholds of power level are required to achieve the energy-saving effect due to the application of ultrasonic in the regeneration. The method of specific energy consumption can be also used for the energy analysis of the new regeneration technology in the scale-up study.     

粉煤灰在废润滑油再生中的应用研究

本文主要介绍粉煤灰在发电厂废润滑油再生中的应用研究。研究表明：粉煤灰是一种优良的吸附剂，节能效果十分明显，其生产成本是目前所采用的各种吸附剂的１／１５～１／５０，不但降低了劳动强度，而且再生油的重要指标都有所提高。     

Catalytic performance of Ni/CeO2/Al2O3 modified with noble metals in steam gasification of biomass

In the steam gasification of biomass, the additive effect of noble metals such as Pt, Pd, Rh and Ru to the Ni/CeO₂/Al₂O₃ catalyst was investigated. Among these noble metals, the addition of Pt was most effective even when the loading amount of added Pt was as small as 0.01 wt.%. In addition, the catalyst characterization suggests the formation of the Pt–Ni alloy over the Pt/Ni/CeO₂/Al₂O₃.