Peroxymonosulfate activation through 2D/2D Z-scheme CoAl-LDH/BiOBr photocatalyst under visible light for ciprofloxacin degradation.

The insecure supply of fossil fuel coerces the scientific society to keep a vision to boost investments in the renewable energy sector. Among the many renewable fuels currently available around the world, biodiesel offers an immediate impact in our energy. In fact, a huge interest in related research indicates a promising future for the biodiesel technology. Heterogeneous catalyzed production of biodiesel has emerged as a preferred route as it is environmentally benign needs no water washing and product separation is much easier. The number of well-defined catalyst complexes that are able to catalyze transesterification reactions efficiently has been significantly expanded in recent years. The activity of catalysts, specifically in application to solid acid/base catalyst in transesterification reaction depends on their structure, strength of basicity/acidity, surface area as well as the stability of catalyst. There are various process intensification technologies based on the use of alternate energy sources such as ultrasound and microwave. The latest advances in research and development related to biodiesel production is represented by non-catalytic supercritical method and focussed exclusively on these processes as forthcoming transesterification processes. The latest developments in this field featuring highly active catalyst complexes are outlined in this review. The knowledge of more extensive research on advances in biofuels will allow a deeper insight into the mechanism of these technologies toward meeting the critical energy challenges in future.

Advances in solid-catalytic and non-catalytic technologies for biodiesel production

Enhanced antibacterial activity and photocatalytic degradation of organic dyes under visible light using cesium lead iodide perovskite nanostructures prepared by hydrothermal method

Photocatalytic degradation was considered as a best strategy for the removal of antibiotic drug pollutants from wastewater. The photocatalyst of ABC (Ag2CO3/BiOBr/CdS) composite synthesized by hydrothermal and precipitation method. The ABC composite used to investigate the degradation activity of tetracycline (TC) under visible light irradiation. The physicochemical characterization methods (e.g. scanning electron microscopy (SEM), transmission electron microscopy (TEM), high resolution-transmission electron microscopy (HR-TEM), ultraviolet visible spectroscopy (UV), photoluminescence (PL) and time resolved photoluminescence (TRPL) clearly indicate that the composite has been construct successfully that enhances the widened visible light absorption, induces charge transfer and separation efficiency of electron – hole pairs. The photocatalytic activity of all samples was examined through photodegradation of tetracycline in aqueous medium. The photocatalytic degradation rate of ABC catalyst could eliminate 98.79% of TC in 70 min, which is about 1.5 times that of Ag2CO3, 1.28 times that of BiOBr and 1.1 times that of BC catalyst, respectively. The role of operation parameters like, TC concentration, catalyst dosage and initial pH on TC degradation activity were studied. Quenching experiment was demonstrated that ·OH and O2·− were played a key role during the photocatalysis process that was evidently proved in electron paramagnetic resonance (EPR) experiment. In addition, the catalyst showed good activity perceived in reusability and stability test due to the synergistic effect between its components. The mechanism of degradation of TC in ABC composite was proposed based on the detailed analysis. The current study will give an efficient and recyclable photocatalyst for antibiotic aqueous pollutant removal. 

Construction of Ag2CO3/BiOBr/CdS ternary composite photocatalyst with improved visible-light photocatalytic activity on tetracycline molecule degradation.

Photocatalysis is a classical solution to energy conversion and environmental pollution control problems. In photocatalysis, the development and exploration of new visible light catalysts and their synthesis and modification strategies are crucial. It is also essential to understand the mechanism of these reactions in the various reaction media. Recently, bismuth and graphene’s unique geometrical and electronic properties have attracted considerable attention in photocatalysis. This review summarizes bismuth-graphene nanohybrids’ synthetic processes with various design considerations, fundamental mechanisms of action, heterogeneous photocatalysis, benefits, and challenges. Some key applications in energy conversion and environmental pollution control are discussed, such as CO2 reduction, water splitting, pollutant degradation, disinfection, and organic transformations. The detailed perspective of bismuth-graphene nanohybrids’ applications in various research fields presented herein should be of equal interest to academic and industrial scientists.

https://www.mdpi.com/1996-1073/14/8/2281/pdf

Bismuth-Graphene Nanohybrids: Synthesis, Reaction Mechanisms, and Photocatalytic Applications—A Review

Lead bismuth oxybromide/graphene oxide: Synthesis, characterization, and photocatalytic activity for removal of carbon dioxide, crystal violet dye, and 2-hydroxybenzoic acid.

One-pot synthesis of acid-base bifunctional catalysts for biodiesel production.

Natural soil and lithium carbonate as economical solid-base catalysts for biodiesel production

Applications of M2ZrO2 (M = Li, Na, K) composite as a catalyst for biodiesel production

Investigation was conducted on bauxite mixed with Li2CO3 as alkali metal catalysts for biodiesel production. Bauxite contains a high percentage of Si and Al compounds among products. Because of the high expense of commercial materials (SiO2, Al2O3) that makes them not economical, the method was very recently improved by replacing commercial materials with Si and Al from bauxite. This is one of the easiest methods for preparing heterogeneous transesterification catalysts, through one-pot blending, grinding bauxite with Li2CO3, and heating at 800 °C for 4 h. The prepared solid-base alkali metal catalyst was characterized in terms of its physical and chemical properties using X-ray powder diffraction and field-emission scanning electron microscopy (FE-SEM). The optimal conditions for the transesterification procedure are to mix methanol oil by molar ratio 9:1, under 65 °C, with catalyst amount 3 wt.%. The procedure is suitable for transesterifying oil to fatty acid methyl ester in the 96% range.

https://www.mdpi.com/2073-4344/9/12/1064/pdf

Yong-Ming Dai

Papers

Lead bismuth oxybromide/graphene oxide: Synthesis, characterization, and photocatalytic activity for removal of carbon dioxide, crystal violet dye, and 2-hydroxybenzoic acid.

One-pot synthesis of acid-base bifunctional catalysts for biodiesel production.

Natural soil and lithium carbonate as economical solid-base catalysts for biodiesel production

Applications of M2ZrO2 (M = Li, Na, K) composite as a catalyst for biodiesel production

Biodiesel Production Using Bauxite in Low-Cost Solid Base Catalyst Precursors