ChemBioEng Reviews最新文献

Passive heat transfer enhancement techniques are gaining attention for their energy efficiency and environmental sustainability, as they eliminate the need for external power. Dimpled surfaces are often preferred as they offer heat transfer augmentation with relatively inferior pressure drop. This critical review examines the influence of various dimple configurations on the thermal-hydraulic performance of tubular heat exchangers. The methodology involves a comparative analysis by focusing on flow dynamics, energy efficiency, and economic analysis. Key findings reveal that dimple-induced mechanisms, such as flow separation, recirculation, vortex formation, and reattachment, significantly enhance convective heat transfer. Elliptical and teardrop dimples generate longitudinal vortices, whereas the inclined dimples promote multidirectional flow. Despite these benefits, dimpled tubes incur higher initial costs and pressure losses, emphasizing the importance of conducting an economic evaluation. This review highlights the limitations of existing literature, a research gap in correlating dimple geometry with a dual focus on thermal and economic aspects.

In pharmaceutical and chemical engineering, addressing newly discovered drugs’ solubility and bioavailability challenges is imperative. Nanoparticle (NP)-based drug delivery systems have emerged as a promising strategy to enhance these compounds’ solubility and overall therapeutic efficacy while minimizing adverse effects. This review presents a comprehensive analysis of synthesis methods for drug-loaded NPs that effectively address solubility limitations. Various chemical synthesizing methods, such as nanoprecipitation, solvent evaporation, and supercritical fluid techniques, are discussed, along with physical methods, including milling, spray-drying, and freeze-drying. Each synthesis approach is evaluated in terms of its underlying principles, advantages, and limitations. Additionally, the importance of NP characterization techniques, such as evaluating drug loading, particle size, and surface properties, is emphasized. Understanding these synthesis methods is crucial for optimizing NP formulations to achieve desired drug delivery outcomes, including improved solubility, controlled release profiles, and targeted delivery to specific sites in the body.

With the increased acceptance, research, and production in the medicinal Cannabis sativa industry, the natural follow-on effect has amplified the amount of cannabis waste generated. This magnification of biomass weight leads to an opportunity coupled with the legislative challenges regarding Δ⁹-tetrahydrocannabinol (THC) content present in the waste that must be destroyed or rendered unusable. It is necessary to find appropriate waste valorization methods to prevent this waste from inhabiting landfills. This study analyzes the waste generated through the production of medicinal cannabis and compares it with the current and potential waste management institutions that are appropriate to handle said waste. Valorization opportunities are discussed for each waste processing method. It has been determined that landfilling is the most unsustainable of cannabis waste management and is limited in generating resource recovery. Current waste management systems can be sustainable for biomass waste but must be embraced by cultivators and industry alike. Novel management methods allow for promising results of waste valorization, but more research is required to determine cannabis suitability.

p-Xylene is a key industrial chemical with increasing demand due to the shift in global markets toward petrochemicals. Although most p-xylene is currently produced through naphtha cracking or naphtha reforming, alternative and cost-effective manufacturing techniques are needed. Catalytic methylation of toluene using shape selective catalysts is a potential route to yield xylenes with great para selectivity. Recent research has focused on modifying catalysts to increase surface acidity, pore channels, and crystallinity, improving para selectivity and toluene conversion. However, challenges remain in designing effective shape selective catalysts without sacrificing catalytic activity and maximizing methanol utilization for increased p-xylene productivity. This review discusses recent developments in catalyst design and modification strategies for improved shape selectivity, including the influence of reaction conditions, kinetics, mechanism, and catalyst deactivation. The review concludes with a forward-looking perspective on developing, designing, and modifying catalysts to address gaps in the related research field.

Traces of impurities encountered after purification processes compromise biodiesel's stability, longevity, and quality performance. Techniques, such as wet washing, adsorbents, and membranes, have been extensively explored; however, they grapple with several challenges, including wastewater generation, time-demanding tasks, and environmentally unfriendly protocols. This study presents a comprehensive overview of solvent-aided crystallization (SAC) as a plausible biodiesel purification option that offers economic and environmental benefits through efficient solvent recovery and minimal waste generation. A total of 23,009 documents published between 2004 and 2024 in the Scopus database were analyzed using a bibliometric approach. This gives insight into research trends, identifies the most extensively explored techniques, highlights countries with a well-established research base in this domain, and offers a guide for evaluation and preference selection for a particular technique. Although conventional methods have been acknowledged for showing great promise in removing impurities such as glycerol and free fatty acids from biodiesel achieving about 98 %, SAC was reported to achieve 99.8 % purity. Moreover, the analysis presented herein underscores the fundamental principles of SAC, factors influencing its efficiency, and the role of selective solubility in enabling effective purification. Finally, it highlights the critical role of strengthened policy action and continued research as key elements, offering researchers valuable insights for advancing the broader adoption and commercialization of SAC.

Bacteriocins and bacteriocin-like inhibitory substances (BLIS) are antimicrobial peptides produced by bacteria with diverse applications in food preservation, pharmaceuticals, and biotechnology. Their practical use depends on efficient purification from complex fermentation broths to ensure bioactivity, purity, and safety. A range of purification techniques have been explored, including ammonium sulfate precipitation, aqueous two-phase systems (ATPS), pH-mediated cell adsorption–desorption, chromatography, and polyethylene glycol (PEG)-impregnated resin systems. Each method offers specific advantages and limitations regarding selectivity, recovery yield, process scalability, and compatibility with downstream operations. Innovation such as ionic liquid-based ATPS has demonstrated improved separation efficiency and milder processing conditions, making them attractive for sensitive biomolecules. Understanding the underlying principles of these methods enables the development of tailored purification workflows that enhance product quality and support the commercialization of bacteriocin-based bioactive agents.

This article explores the integration of four-dimensional (4D) printing technologies with automation and miniaturization using the theory of inventive problem-solving (TRIZ) methodology. The patent landscape and technological trends were analyzed, revealing gaps in current solutions, particularly regarding dynamic materials in automation systems. Key findings indicate significant advancements in the development of responsive materials and automation systems that improve the efficiency, scalability, and precision of biomanufacturing. Solutions, such as modular automation systems for handling dynamic materials, have been designed and evaluated through simulations and pilot tests, demonstrating their feasibility and effectiveness.

Water contamination by organic and inorganic toxicants is a critical issue that needs to be successfully resolved using efficient remediation methodologies. Inorganic metal and nonmetal ions toxicants are contributed from industrial, urbanization, domestic, and natural activities to the water resources, and water-mediated consumption of these toxicants beyond the prescribed limit causes stern health problems for humans and other living beings and creates ecological imbalances. Polyaniline nanocomposites fabricated using various organic and inorganic nanomaterials attracted great attention in water purification owing to enhanced surface, physicochemical features, and better pollutant removal capacity. This review discusses recent advances in polyaniline nanocomposites as adsorbents for the removal of metallic and nonmetallic water pollutants, including key synthesis approaches, adsorption potential, and mechanisms followed in the exclusion of inorganic pollutants. It is deduced that polyaniline nanocomposites are efficient adsorbents for metallic and nonmetallic inorganic water pollutants. It concluded with major outcomes and challenges associated with the discussed adsorbents.

Algae for biofuels as an alternative to fossil fuels. Copyright: toa555@AdobeStock