Volume 41, Issue 1

Halogenation reactions are a vital area of study for the pharmaceutical industry. The study of the reaction conditions along with the reactors and their scale-up is a thrust area in drug synthesis and manufacturing. There is a shift in the research community towards accommodating renewable energy sources which has driven scientists to include energy sources that are sustainable and aid in making the overall process efficient. This review provides a comprehensive overview of the challenges in selecting the best catalyst, light source and reaction conditions for the fluorination, chlorination and bromination reactions. This paper goes a step further to explain the photoreactors’ design and modelling as well as the scale-up of the same. Overall, it provides a comprehensive view of diverse scientific areas, from halogenation in drug synthesis to the potential of photochemical batch and flow approaches in halogenation reactions.

A review of the available information about the packed bed reactors with cocurrent upflow of gas and liquid (UFRs), particularly focused on heat transfer with an external medium through the container wall, was undertaken in this contribution. The typical use of such reactors is summarized as well as some novel applications. A brief discussion about fluid-dynamics is also made due to its strong effect on the transport processes. Experimental setup, available data, and literature correlations of heat transfer parameters are thoroughly reviewed. From a critical analysis of the experimental data, a refined database has been built, which allows comparing the performance of the existing correlations for the two parameters of the extensively employed two-dimensional pseudo-homogeneous plug flow model ( i.e. , effective radial thermal conductivity and wall heat transfer coefficient). In addition, new correlations for these parameters have been developed, which allow improving the actual predictive capabilities. Finally, the global heat transfer between the bed and the wall was comparatively analyzed for upflow (UFRs) and downflow (TBRs) gas–liquid packed bed reactors.

Considering the distinctive features of the delayed coking process and taking into account various particulate matter control technologies, the feasibility of using jet washing technology to remove coke powder from process gas is explored. The performance of scrubbers is heavily reliant on the quality of atomization, which in turn is influenced by liquid jet breakup. Due to the multiple interactions of various instabilities involved in jet breakup, as well as the short duration and small scale of this process, it is challenging to observe experimentally. Therefore, the specific fluid dynamics processes are not yet clear. In recent years, extensive research has been conducted on research methods, jet breakup modes, jet breakup characteristics, and jet breakup mechanisms. However, there is a lack of comprehensive review work summarizing these research advancements. This article aims to provide a comprehensive overview to facilitate jet scrubber designers’ systematic understanding of progress in jet breakup research. Furthermore, it discusses the significance of studying confined spaces for jet breakup with the objective of providing valuable insights for designing and optimizing delayed coker.

Comminution processes play a pivotal role in diverse applications, ranging from food processing, to mining and materials engineering. The pharmaceutical industry is no exception, with an increased focus on particle engineering to overcome the growing challenges related to the complexity of new drug molecules such as poor water solubility or stability issues. Additionally, the preparation of powders for pulmonary, transdermal, topical, ophthalmic, oral or parenteral administration often requires specific particle size requirements. Thus, milling technologies offer an excellent option for controlling particle size, improving the stability, dissolution, absorption rate, and bioavailability of poorly water-soluble drugs. They also contribute to enhancing pharmaceutical forms and overall product performance. This review highlights the different types of technologies used for comminution, the respective advantages and drawbacks, as well as connected topics including feed material properties, analytical techniques, process analytical technology, process safety, new top-down technologies and key information to consider when selecting a technology. Thus, an in-depth approach of comminution in the pharmaceutical industry is presented. This compilation serves as a source of comprehensive information for those who decide to initiate research projects in this field, or to update their existing literature knowledge and understanding.