Dual-functional Ag3PO4@palygorskite composite for efficient photodegradation of alkane by in situ forming Pickering emulsion photocatalytic system

Application of natural minerals in photocatalytic degradation of organic pollutants: A review

Photocatalysis is an effective, inexpensive and environmentally friendly technology for the decomposition of various aqueous organic pollutants and plays an increasingly critical role in the degradation of pollutants. Natural minerals are abundant natural resources on Earth and can be obtained directly from nature. Natural minerals are excellent photocatalyst carriers that are environmentally friendly, low in price, and will not cause secondary pollution to the environment. Natural minerals have the characteristics of a large specific surface area, providing more active centres, and adsorbing pollutants to concentrate catalysis. Natural minerals are also excellent photocatalysts, such as haematite and magnetite, which play a very good role in the degradation of water pollutants. Studies that make full use of natural minerals are of great significance. This review covers the latest research on natural minerals as photocatalytic composite materials to degrade organic pollutants in water, including three parts: the classification of natural minerals, the structural description of natural mineral composites, and the photocatalytic degradation of organic pollutants by natural mineral composites. In addition, the current limitations and opinions of natural mineral composites are discussed to achieve better results in applying natural minerals.

Recent advances on nanocellulose biomaterials for environmental health photoremediation: An overview

As one of the potential bionanomaterials, nanocellulose has appeared as a favorable candidate for photoremediation of the environment because of its abundance in nature, inexpensive, eco-friendly, decomposable, high surface area, and outstanding mechanical properties. The current review carefully summarized the diverse type of nanocellulose, their preparation approaches, and several previous works on the use of nanocellulose for photoremediation. These include the role of nanocellulose for the increased surface active site of the hybrid photocatalysts by providing a large surface area for enhanced adsorption of photons and pollutant molecules, as a dispersing agent to increase distribution of metal/non-metal dopants photocatalysts, as well as for controlled size and morphology of the dopants photocatalysts. Furthermore, the recommendations for upcoming research provided in this review are anticipated to ignite an idea for the development of other nanocellulose-based photocatalysts. Other than delivering beneficial information on the present growth of the nanocellulose biomaterials photocatalysts, this review is expected will attract more interest to the utilization of nanocellulose photocatalyst and distribute additional knowledge in this exciting area of environmental photoremediation. This could be attained by considering that a review on nanocellulose biomaterials for environmental health photoremediation has not been described elsewhere, notwithstanding intensive research works have been dedicated to this topic.

Deep remediation of oil spill based on the dispersion and photocatalytic degradation of biosurfactant-modified TiO2

The employment of dispersant was an effective method to treat marine oil spill pollution. However, conventional dispersants only showed a single oil dispersion. Here, by modifying TiO₂ nanoparticles with biosurfactant-Rhamnolipids (Rha), a highly efficient particulate dispersant with photocatalytic activity was developed. Rha-TiO₂ showed both excellent oil spill dispersion and facilitated photodegradation for oil simultaneously. The oil droplets dispersed by Rha-TiO₂ in seawater exhibited long time stability, which indicated the synergistic emulsification interactions between TiO₂ and Rha in artificial sea water (ASW). The dispersion mechanism of Rha-TiO₂ was analyzed, we found the TiO₂ nanoparticles alone weren't effectively emulsified oil in high salinity ASW, but the addition of a small amount of Rha could modify the surface wettability of TiO₂ nanoparticles to form the stable emulsion. In addition, the addition of a small amount of Rha could reduce the surface tension of the oil-water interface, which contribute to increasing the content of TiO₂ nanoparticles at the oil-water interface, form a steric rigid layer around the oil droplets to prevent droplet coalescence and facilitate the further photocatalytic degradation of oil. In short, the Rha-TiO₂ nanoparticles could effective disperse oil in ASW, meanwhile the TiO₂ also played the role of photocatalytic degradation of oil pollution. Hence, this study developed a novel photocatalytic particulate dispersant to remediate marine oil spill and delivered a new feasible solution for practical oil spill treatment in the future.

Multiphase Microreactors Based on Liquid-Liquid and Gas-Liquid Dispersions Stabilized by Colloidal Catalytic Particles

Pickering emulsions, foams, bubbles, and marbles are dispersions of two immiscible liquids or of a liquid and a gas stabilized by surface‐active colloidal particles. These systems can be used for engineering liquid–liquid–solid and gas–liquid–solid microreactors for multiphase reactions. They constitute original platforms for reengineering multiphase reactors towards a higher degree of sustainability. This Review provides a systematic overview on the recent progress of liquid–liquid and gas–liquid dispersions stabilized by solid particles as microreactors for engineering eco‐efficient reactions, with emphasis on biobased reagents. Physicochemical driving parameters, challenges, and strategies to (de)stabilize dispersions for product recovery/catalyst recycling are discussed. Advanced concepts such as cascade and continuous flow reactions, compartmentalization of incompatible reagents, and multiscale computational methods for accelerating particle discovery are also addressed.

Removal of antibiotics from aqueous solution by using porous adsorbent templated from eco-friendly Pickering aqueous foams

The aqueous foam template without any solvent and only using the particles stabilizer has attracted much attention for preparation of the porous adsorbents. Herein, a novel porous adsorbent was fabricated via thermal-initiated polymerization of Pickering aqueous foams, which was stabilized by the natural sepiolite (Sep) and pine pollen, and utilized for the removal of antibiotic from aqueous solution. The stabilizing mechanism of Pickering aqueous foam of that the Sep was modified with the leaching substance from pine pollen and arranged orderly around the bubble to form a dense "shell" structure was revealed. The adsorbents possessed the hierarchical porous structure and excellent adsorption performance for antibiotic of chlorotetracycline hydrochloride (CTC) and tetracycline hydrochloride (TC). The equilibrium adsorption capacities of CTC and TC were achieved with 465.59 and 330.59 mg/g within 60 min at 25°C, respectively. The adsorption process obeyed Langmuir model and pseudo-second-order adsorption kinetic model. This work provided eco-friendly approach for fabricate porous adsorbents for wastewater treatment.