Recent advances in dual-filler mixed matrix membranes

Mixed matrix membranes (MMMs) have been widely developed as an attractive solution to overcome the drawbacks found in most polymer membranes, such as permeability-selectivity trade-off and low physicochemical stability. Numerous fillers based on inorganic, organic, and hybrid materials with various structures including porous or nonporous, and two-dimensional or three-dimensional, have been used. Demanded to further improve the characteristics and performances of the MMMs, the use of dual-filler instead of a single filler has then been proposed, from which multiple effects could be obtained. This article aims to review the recent development of MMMs with dual filler and discuss their performances in diverse potential applications. Challenges in this emerging field and outlook for future research are finally provided.

Effective factors on performance of zeolite based metal catalysts in light hydrocarbon aromatization

Aromatic hydrocarbons are essential compounds, that the presence of which in fuels can improve the octane number. The conversion of the light alkanes to high value aromatics is vital from theoretical and industrial standpoints. Zeolites such as ZSM-5 play an essential role in the aromatization of light alkanes. This paper highlights the mechanism of aromatization of light alkanes such as methane, ethane, propane, butane, and its isomers. Furthermore, effective factors on the aromatization of light alkanes including metal type, crystallinity, acidity, space velocity, pretreatment of zeolites, co-feeding of light hydrocarbon, and operating factors such as temperature have been investigated to determine how a system of zeolite with metals can be useful to reach aromatization with high conversion.

Advances and challenges in the development of nanosheet membranes

The development of highly efficient separation membranes utilizing emerging materials with controllable pore size and minimized thickness could greatly enhance the broad applications of membrane-based technologies. Having this perspective, many studies on the incorporation of nanosheets in membrane fabrication have been conducted, and strong interest in this area has grown over the past decade. This article reviews the development of nanosheet membranes focusing on two-dimensional materials as a continuous phase, due to their promising properties, such as atomic or nanoscale thickness and large lateral dimensions, to achieve improved performance compared to their discontinuous counterparts. Material characteristics and strategies to process nanosheet materials into separation membranes are reviewed, followed by discussions on the membrane performances in diverse applications. The review concludes with a discussion of remaining challenges and future outlook for nanosheet membrane technologies.

Big data analytics opportunities for applications in process engineering

Big data is an expression for massive data sets consisting of both structured and unstructured data that are particularly difficult to store, analyze and visualize. Big data analytics has the potential to help companies or organizations improve operations as well as disclose hidden patterns and secret correlations to make faster and intelligent decisions. This article provides useful information on this emerging and promising field for companies, industries, and researchers to gain a richer and deeper insight into advancements. Initially, an overview of big data content, key characteristics, and related topics are presented. The paper also highlights a systematic review of available big data techniques and analytics. The available big data analytics tools and platforms are categorized. Besides, this article discusses recent applications of big data in chemical industries to increase understanding and encourage its implementation in their engineering processes as much as possible. Finally, by emphasizing the adoption of big data analytics in various areas of process engineering, the aim is to provide a practical vision of big data.

Review of potential flow solutions for velocity and shape of long isolated bubbles in vertical pipes

The motion of elongated gas bubbles in vertical pipes has been studied extensively over the past century. A number of empirical and numerical correlations have emerged out of this curiosity; amongst them, analytical solutions have been proposed. A review of the major results and resolution methods based on a potential flow theory approach is presented in this article. The governing equations of a single elongated gas bubble rising in a stagnant or moving liquid are given in the potential flow formalism. Two different resolution methods (the power series method and the total derivative method) are studied in detail. The results (velocity and shape) are investigated with respect to the surface tension effect. The use of a new multi-objective solver coupled with the total derivative method improves the research of solutions and demonstrates its validity for determining the bubble velocity. This review aims to highlight the power of analytical tools, resolution methods and their associated limitations behind often well-known and wide-spread results in the literature.