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Process Intensification (PI) is a vast and growing area in Chemical Engineering, which deals with the enhancement of current technology to enable improved efficiency; energy, cost, and environmental impact reduction; small size; and better integration with the other equipment. Since process intensification results in novel, but complex, systems, it is necessary to rely on optimization and control techniques that can cope with such new processes. Therefore, this review presents some advancements in the field of process intensification that are worthy of exploring in detail in the coming years. At the end, several important open questions that can be taken into consideration in the coming years are listed.

Environmental pollution, particularly that caused by the presence of heavy metals in wastewater, is a serious problem. Therefore, heavy metals should be prevented from reaching the natural environment or removed from polluted wastewater. Adsorption is a very economical, simple, effective, highly versatile process for removing harmful pollutants from wastewater. In this study, six commercial activated carbon (AC) samples were used to evaluate the adsorption of Pb2+, Ni2+, and Zn2+. We investigated the correlation between the adsorption of metal ions on AC and the pore or surface properties of AC. Large quantities of ions in the order [Pb2+] >> [Zn2+], [Ni2+] were adsorbed on all AC samples. The results showed that the Pb2+ adsorption capacity per unit Dubinin–Polanyi (DP) surface area (SDP) is correlated with the graphite/defect (G/D) ratio of AC; the G/D ratio was analyzed via Raman spectroscopy. The adsorbability of Pb2+ on AC per unit SDP was higher in AC with a larger G/D ratio. Moreover, we found that hard and soft acids and bases contribute to adsorption. The observed correlation facilitates the determination of the adsorption capacity of Pb2+ on AC using the G/D ratio without any adsorption test.

Microreactors and micro heat exchangers have very unique characteristics due to the small size of their channels. Our close examination of the properties of microchemical systems has resulted in the finding that microchannel reactor systems have modular structures, a feature which may be exploited to create novel systems. In microreactors, reagents are mixed in a dedicated device while another microchannel is used to exchange heat. For this reason, the chemical reactor, which is conventionally treated as a unit operation, may be decomposed into more elementary operations, thereby enabling the development of new chemical apparatuses by reconfiguring the individual modules. This presentation introduces a conceptual framework for the elementary operation of these chemical apparatuses. An example of the application of these concepts to the development of a new distillation device will be discussed.

Basic copper acetate can be obtained by mixing copper acetate with sodium hydroxide solutions. However, the quality of the resulting crystals is usually poor. An unknown peak appears in its X-ray diffraction pattern, and moreover, the intensity of the peak varies from sample to sample. In this study, effect of mixing methods on the quality of the basic copper acetate crystals was studied. The crystals were synthesized by employing three different mixing methods, which were batch, semi-batch system, and micromixer. The intensity of the unknown peak weakened when the semi-batch system was employed. The results implied that the mixing rate gave strong influence on the quality of the resulting basic copper acetate crystals.

Isosteric heat of adsorption is indispensable in probing the energetic behavior of interaction between adsorbate and solid, and it can shed insight into how molecules interact with a solid by studying the dependence of isosteric heat on loading. In this study, we illustrated how this can be used to explain the difference between adsorption of non-polar (and weakly polar) fluids and strong polar fluids on a highly graphitized carbon black, Carbopack F. This carbon black has a very small quantity of functional group, and interestingly we showed that no matter how small it is the analysis of the isosteric heat versus loading can identify its presence and how it affects the way polar molecules adsorb. We used argon and nitrogen as representatives of non-polar fluid and weakly polar fluid, and methanol and water for strong polar fluid. The pattern of the isosteric heat versus loading can be regarded as a fingerprint to determine the mechanism of adsorption for strong polar fluids, which is very distinct from that for non-polar fluids. This also allows us to estimate the interplay between the various interactions: fluid-fluid, fluid-basal plane and fluid-functional group.