Availability of elements for heterogeneous catalysis: Predicting the industrial viability of novel catalysts

Growing concern regarding the sustainability of the chemical industry has driven the developmentof more efficient catalytic reactions.First‐generation estimates of catalyst viability are based oncrustal abundance,which has severe limitations.Herein,we propose a second‐generation approachto predicting the viability of novel catalysts prior to industrial implementation to benefit the globalchemical industry.Using this prediction,we found that a correlation exists between catalyst consumptionand the annual production or price of the catalyst element for11representative industrialcatalytic processes.Based on this correlation,we have introduced two new descriptors for catalystviability,namely,catalyst consumption to availability ratio per annum(CCA)and consumed catalystcost to product value ratio per annum(CCP).Based on evaluations of CCA and CCP for selected industrial reactions,we have grouped catalysts from the case studies according to viability,allowing the identification of general limits of viability based on CCA and CCP.Calculating the CCA and CCP and their comparing with the general limits of viability provides researchers with a novel framework for evaluating whether the cost or physical availability of a new catalyst could be limiting.We have extended this analysis to calculate the predicted limits of economically viable production and product cost for new catalysts.?2018,Dalian Institute of Chemical Physics,Chinese Academy of Sciences.Published by Elsevier B.V.All rights reserved.

Operational Robustness Studies of Solid Oxide Electrolysis Stacks

Stacks of solid oxide cells which can be run as both electrolysers and fuel cells have been tested for robustness towards simulations of stress conditions which are likely to occur during operation of solid oxide electrolysis systems, for which the energy supply comes from renewable sources, such as wind mills and solar cells. Such conditions are thermo mechanical stress conditions as well as loss of fuel and air supply. The cells have Ni/YSZ （yttria stabilized zirconia） fuel electrodes, YSZ electrolytes, and LSCF （lanthanum strontium cobalt ferrite） oxygen electrodes with a CGO （cerium gadolinium oxide） barrier layer. In the stacks, the cells are separated by chromium rich steel interconnects. The robustness tests of stacks are one step in the development of a SOEC （solid oxide electrolysis cell） core; the core component in a SOEC system, including one or more SOEC stacks, heaters, heat exchangers, insulation, and feed troughs.

Injection of gas-liquid jets into gas-solid fluidized beds:A review

Injection of gas-liquid sprays into gas-solid fluidized beds finds application in many industries.Effective mixing and distribution of liquid feed and solid bed material is paramount to ensure an efficient and profitable process.Despite its long-term use,the mechanism of liquid injection into gas-solid fluidized beds continues to raise questions and is only partially understood.This paper provides a thorough and up-to-date review of experimental and numerical investigations of gas-liquid sprays into gas-solid fluidized beds conducted over the past decades.Based on the surveyed literature,a phenomenological description of the prevalent mechanisms of gas-liquid injection under different operating conditions is presented.This review identifies suitable computational fluid dynamic models for simulating the mechanisms involved in gas-liquid-solid interactions along with recommendations for future numer-ical and experimental work.

Cu／ZnO甲醇合成催化剂的瞬变行为

对铜-氧化锌催化剂下的甲醇合成反应进行时间分辨测定时，发现一种取决于预处理气体组成的瞬间甲醇生产。确切地说，该甲醇产品的首次产量极大值，出现在对氢气和CO的中间混合气体进行预处理的时候（CO中H2比例为20％-80％）。其活性测量结果在可比较的反应条件时，与环境透射电子显微镜（ETEM）中在ZnO载体上的铜纳米粒子的观察结果具有可比性。在气体混合物组成为H2：CO=1：1时，环境透射电子显微镜的图像揭示了具有明显扁平形状的一种铜纳米粒子的气体依附形态。这种铜纳米粒子的气体依附形态为在瞬间甲醇生产和在由Ovesen等人提出的动态微动力学模型的框架内所观察到的预处理条件之间的偶合提供了一致性的解释。