The article contains sections titled: 1. Introduction 2. Properties 2.1. Physical Properties 2.2. Chemical Properties 3. Production of Natural Fatty Acids 3.1. Resources and Raw Materials 3.2. Fat Splitting 3.2.1. Hydrolysis – Principles 3.2.2. Hydrolysis – Industrial Procedure 3.2.3. Hydrolysis – Enzymatic Processes 3.3. Separation of Fatty Acids 3.3.1. Distillation 3.3.2. Crystallization 3.4. Modification of Fatty Acids 3.4.1. Hydrogenation 3.4.2. Double Bond Isomerization 3.4.3. Dehydration 3.4.4. Dimerization 3.4.5. Ozonolysis 3.4.6. Thermal Decomposition 3.4.7. Bio‐Oxidation of Fatty Acids 3.4.8. Enzymatic Esterification 4. Production of Synthetic Fatty Acids 4.1. Hydroformylation 4.2. Hydrocarboxylation 4.3. Other Commercial and Noncommercial Processes 5. Analysis 6. Storage and Transportation 7. Environmental Protection, Toxicology and Occupational Health 8. Uses 9. References

Although dividing-wall columns are now well established in industrial practice, their complex hydraulics is not well understood, and open literature does not provide any quantitative information in this respect. This study aims to provide the missing knowledge. Hence, a pilot plant was built to separate a ternary mixture of fatty alcohols into high-purity products of ∼99 wt %. A model was established to simulate this separation process. It could successfully describe the experiments quantitatively and even account for the self-adjustment of the vapor splits. A case study with the validated model highlighted the strong influence of the heat transfer across the vertical partition wall on hydrodynamics and vapor distribution. These aspects are of special interest for the design and scale-up of dividing-wall columns.

Simultaneous and sequential adsorption equilibria of single and binary adsorption of bovine serum albumin and bovine hemoglobin on Q Sepharose FF were investigated in different buffer constituents and initial conditions. The results in simultaneous adsorption showed that both proteins underwent competitive adsorption onto the adsorbent following greatly by protein-surface interaction. Preferentially adsorbed albumin complied with the universal rule of ion-exchange adsorption whereas buffer had no marked influence on hemoglobin adsorption. Moreover, an increase in initial ratios of proteins was benefit to a growth of adsorption density. In sequential adsorption, hemoglobin had the same adsorption densities as single-component adsorption. It was attributed to the displacement of preadsorbed albumin and multiple layer adsorption of hemoglobin. Three isothermal models (i.e. extended Langmuir, steric mass-action, and statistical thermodynamic (ST) models) were introduced to describe the ion-exchange adsorption of albumin and hemoglobin mixtures. The results suggested that extended Langmuir model gave the lowest deviation in describing preferential adsorption of albumin at a given salt concentration while steric mass-action model could very well describe the salt effect in albumin adsorption. For weaker adsorbed hemoglobin, ST model was the preferred choice. In concert with breakthrough data, the research further revealed the complexity in ion-exchange adsorption of proteins.

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Molecular dynamics (MD) simulations with coarse-grained models are used to investigate the adsorption process of proteins onto an ion-exchange chromatographic medium. The adsorption of human serum albumin (HSA) and bovine hemoglobin (bHb) on the anion exchanger Q Sepharose FF is studied. These two proteins have similar molecule sizes with different isoelectric points. To obtain a reliable set of data, simulations with different initial conditions are carried out for each protein. Convincingly, the results of the MD simulations are qualitatively consistent with those of previous experiments. HSA reaches a stable adsorption in all simulations, while the binding sites can differ. In contrast, bHb reaches a stable adsorption only in one simulation. Due to the stronger protein–ligand interaction of HSA, it adsorbs faster, stronger, and with more binding sites onto Q Sepharose FF than bHb. The spatial movements during the adsorption process and the adsorbed states are investigated in detail. Moreover, we studied the underlying physical relevance of two parameters (characteristic charge and steric factor) of the steric mass action (SMA) model for HSA and for bHb with MD simulations and compared them with the results of experiments. The results reveal that MD simulations are useful to interpret the physical consistence of the SMA parameters.