The second part of this compendium concludes with a collection of phase change enthalpies of organic molecules inclusive of C11–C192 reported over the period 1880–2015. Also included are phase change enthalpies including fusion, vaporization, and sublimation enthalpies for organometallic, ionic liquids, and a few inorganic compounds. Paper I of this compendium, published separately, includes organic compounds from C1 to C10 and describes a group additivity method for evaluating solid, liquid, and gas phase heat capacities as well as temperature adjustments of phase changes. Paper II of this compendium also includes an updated version of a group additivity method for evaluating total phase change entropies which together with the fusion temperature can be useful in estimating total phase change enthalpies. Other uses include application in identifying potential substances that either form liquid or plastic crystals or exhibit additional phase changes such as undetected solid–solid transitions or behave ani...

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Phase Transition Enthalpy Measurements of Organic and Organometallic Compounds and Ionic Liquids. Sublimation, Vaporization, and Fusion Enthalpies from 1880 to 2015. Part 2. C11–C192

Challenges in process optimization for new feedstocks and energy sources

Multi-criteria optimization in chemical process design and decision support by navigation on Pareto sets

The number of design and processing requirements in the chemical and biochemical industries are increasing to adapt to rapidly changing markets and the global competition, as well as to shift toward more sustainable production and to meet the need for new and innovative products. Hence, more efficient processes are needed. Reactive and membrane-assisted distillation can achieve higher efficiencies and high capacities. They are believed to be important technologies for retrofitting existing processes and for incorporation into future processes for efficient and flexible (bio)chemical production. This manuscript aims to briefly summarize past research with a more detailed view on current research areas within the application, modeling, design and optimization of reactive- and membrane-assisted distillation processes, with a special focus on pervaporation, vapor permeation and organic solvent nanofiltration. By identifying the current challenges combined with future perspectives of the chemical processing industry, a personal opinion on future research trends, needs and challenges for these technologies is given. These technologies need to be addressed to increase trust in the potential and reliability of reactive- and membrane-assisted distillation, which would enable the intensification of manufacturing processes.

Reactive and membrane-assisted distillation: Recent developments and perspective

Process optimization for two or more objectives is increasing Since objectives are often conflicting, multi-objective optimization (MOO) provides many Pareto-optimal solutions, quantitative trade-off between objectives, optimal values of decision variables and their trends These results give greater insight about the process and are useful for selecting one of the optimal solutions In this paper, MOO is introduced and compared with single objective optimization, and then MOO studies on design of energy efficient processes, published from January 2013 to February 2015, are reviewed MOO applications in 65 papers of interest to chemical engineers, are classified into four groups: energy efficient processes, biofuels, power generation/CO2 capture, and fuel cell/hydrogen production Main features of these studies are summarized in four tables Finally, concluding remarks are given for future studies on MOO applications

Multi-objective optimization for the design and operation of energy efficient chemical processes and power generation

Hybrid separations combining distillations and crystallisations have a significant potential for process intensification. To address the large number of degrees of freedom in the design of hybrid separations, a three-step approach is utilised. However, it can only be applied if all parameters for the rigorous modelling of crystallisation and cost functions are known a priori, which is often not the case. In this paper, we propose a four-step design method which can be applied in early process development stages when not all model parameters are available. In the first step, different process variants are generated. In the second step, the variants are evaluated using rigorous models, wherein the unknown model parameters are varied to quantify their influence on the process performance. If hybrid separations appear to be compatible, experiments are performed to determine the unknown parameters in the third step. In the last step, an optimisation is performed to find the optimal process, when necessary in dependence of unknown cost parameters. The developed tools and the feasibility of the approach are illustrated with the separation of a binary mixture of long-chain isomeric aldehydes.

Design of hybrid distillation/melt crystallisation processes for separation of close boiling mixtures

Melt crystallization of isomeric long-chain aldehydes from hydroformylation

Separation of the isomeric long-chain aldehydes dodecanal/2-methylundecanal via layer melt crystallization

Layer melt crystallization is a highly selective method for the separation of narrow boiling mixtures which are difficult to separate with conventional separation techniques like distillation due to low driving forces. Contrawise, layer melt crystallization has the drawback of limited capacity due to the direct connection between crystal product and required cooled surface. Here, the combination of the high throughput distillation and highly selective layer melt crystallization into an integrated hybrid process can lead to enormous benefits. Since the separation efficiency of the crystallization is not predictable, it has to be described with empirical correlation. Here, studies from literature use strongly simplified correlations by, e.g. assuming complete separation. This bears the serious risk of overestimating the efficiency of the hybrid process. Further, the effective post purification step sweating was not implemented into hybrid processes in studies from literature. This study fills this gap in literature. A distilliation/melt crystallization hybrid process is optimized by realistically describing crystallization separation efficiency and by implementing sweating. The required crystallization models are presented and experimentally validated. The optimization of the hybrid process is done with different modelling depths and the results underline impressively the importance of the adequate description of the crystallization separation efficiency.

Using complex layer melt crystallization models for the optimization of hybrid distillation/melt crystallization processes

Li‐ion batteries (LIBs) in electric vehicles (EVs) are usually operated intermittently and maintained at high states of charge (SoCs) for long periods. Because the internal particles of Ni‐rich cathodes are easily exposed to the electrolyte at high SoCs owing to mechanical instability, the electrolyte exposure time—during which highly reactive Ni4+ ions react with the electrolyte—critically affects the degradation of the cathode. Here, 1 mol% B doping of a core–shell concentration gradient (CSG) Li[Ni0.88Co0.10Al0.02]O2 cathode (CSG‐NCA88) is shown to dramatically alter the microstructure of the cathode and effectively protect the particle interior from parasitic electrolyte attack. The B‐doped CSG‐NCA88 cathode, CSG‐NCAB87, maintains its original microstructure even after holding for 500 h in the fully charged state, whereas irreversible structural damage occurs in the pristine CSG‐NCA88 cathode during the prolonged electrolyte exposure. The long‐term cycling results confirm that the capacity retention of the cathodes is determined by the electrolyte exposure time at a high SoC and that microstructural modification can effectively suppress the time‐dependent degradation from electrolyte attack. The proposed CSG‐NCAB87 cathode can be utilized at full capacity without restricting the SoC, thus realizing the development of economical high‐energy‐density LIBs.

Thorsten Beierling

Papers

Design of hybrid distillation/melt crystallisation processes for separation of close boiling mixtures

Melt crystallization of isomeric long-chain aldehydes from hydroformylation

Separation of the isomeric long-chain aldehydes dodecanal/2-methylundecanal via layer melt crystallization

Using complex layer melt crystallization models for the optimization of hybrid distillation/melt crystallization processes

High‐Energy Ni‐Rich Cathode Materials for Long‐Range and Long‐Life Electric Vehicles