Introduction: This study explored the synthesis, characteristics, and catalytic performance of copper-impregnated activated carbon (Cu/GSAC) derived from waste groundnut shells for phenol degradation via catalytic wet peroxide oxidation (CWPO). Method: The Groundnut shell activated carbon (Cu/GSAC) catalyst was prepared by activating the carbon with H2SO4 and copper nitrate impregnation, creating a high surface area. Batch oxidation was performed. Result: Under optimized CWPO conditions (0.5 g catalyst, 20 mL of 30% H2O2, pH 5, 4 h reaction time), phenol removal reached about 85%, notably higher than the 42.5% removal achieved by adsorption alone. The CWPO process demonstrated excellent energy efficiency due to its operation under mild conditions and low energy requirements. Discussion: Furthermore, the catalyst showed strong reusability, maintaining over 80% degradation efficiency after four cycles, with minimal copper leaching (<0.8 ppm). Conclusion: Overall, the study highlights the potential of converting abundant agro-waste such as groundnut shells into an efficient, stable, and environmentally friendly Cu-based catalyst, offering a cost-effective and sustainable route for treating phenolic wastewater, coke oven waste water of steel plants, refinery wastewater, etc.
Abstract: Corrosion is a significant economic, safety, and environmental concern in Enhanced Oil Recovery (EOR) operations. Traditional corrosion inhibitors are effective in some cases; however, their toxicity and environmental impact often render them unsuitable. Biopolymers represent a renewable and eco-friendly alternative for addressing corrosion- related issues. Lignin, sodium alginate, chitosan, and cellulose are representative examples of such biopolymers. Because biopolymers are generally non-toxic, biodegradable, and renewable, they constitute a promising substitute for synthetic inhibitors. Biopolymers form an external protective layer on the metal surface, thereby reducing corrosion rates and limiting direct contact between the metal and the corrosive environment. For instance, lignin and sodium alginate have demonstrated very high corrosion-inhibition efficiencies, supporting their potential as replacements for synthetic corrosion inhibitors. Biopolymers can therefore provide effective corrosion-control solutions for EOR operations while delivering sustainability benefits and reducing environmental impact on a global scale. However, challenges remain in scaling biopolymer applications to the industrial level, ensuring long-term operational durability, maintaining compatibility with other chemicals used in EOR operations, and achieving broader applicability and scalability. Future research should focus primarily on developing hybrid or dual biopolymer systems to evaluate their combined potential for corrosion inhibition, as well as assessing biopolymer performance under conditions of high salinity, elevated temperature, and acidic reservoir environments. Overall, biopolymers not only enhance the efficiency of oil recovery but also contribute to environmental sustainability. Therefore, continued research on biopolymers as a corrosion-inhibition strategy is warranted, positioning them as a long-term pathway toward greener and more sustainable corrosion-inhibition approaches.
Introduction: Spirulina platensis, a cyanobacterium used in food and health products, faces high cultivation costs due to synthetic media requirements. This study explores the use of sugar mill effluent (SME) as a supplement to Zarrouk's medium, aiming to lower production costs and aid in pollutant removal from wastewater. Materials and Methods: Physicochemical and nutritional aspects of SME were investigated. Spirulina platensis (NCIM 5143) was cultivated in Zarrouk’s medium supplemented with 50-100 mL/L of SME for 20 days. Studies were performed on biomass, biochemical composition, pigments, oxidative stress, heavy metals, and phycoremediation efficiency. Results: SME was nutrient-rich, containing 245 mg/L N, 28.5 mg/L P, and 310 mg/L K+. Growth increased significantly with SME concentration (p < 0.05), with SP4 producing maximum biomass, protein, pigments, and phycocyanin. Heavy metals remained within permissible limits, while COD and BOD removal reached 58.3% and 62.1%, respectively. Discussion: SME enhancement increased the biomass and biochemical composition of Spirulina by providing it with organic carbon and essential nutrients, which provided a cheaper option compared to the conventional Zarrouk’s medium. Elevated malondialdehyde and antioxidant pigments indicated increased oxidative stress. Moreover, Spirulina production allowed for sustainable pollutant disposal through SME reuse. Conclusion: Sugar mill effluent supplementation (100 mL/L) significantly improved the growth and biomass productivity of Spirulina platensis, while also enhancing pigment synthesis and achieving effective phycoremediation, resulting in 62% BOD and 58% COD removal. This method enables sustainable, cost-effective cultivation, reduces pollution, and produces safe biomass.
Background and Objective: Microwave-Assisted Synthesis (MAS) is a process- intensification technology that offers rapid volumetric heating, improved reaction control, shorter reaction durations, and energy and solvent savings compared to conventional heating. This comprehensive review objectively examines principles, reactor technologies, applications, scale-up prospects, and limitations of MAS in chemical and related sciences. Methods: A systematic review was conducted in accordance with using PRISMA 2020 guidelines. PubMed/MEDLINE, Scopus, Web of Science, ScienceDirect, and Google Scholar databases were searched from inception to May 2026. Qualifying studies were selected by two reviewers independently. Methodological quality was assessed using Joanna Briggs Institute critical appraisal techniques, and findings were synthesised qualitatively due to methodological and technological heterogeneity. Results: Among 1,264 records, 164 duplicates were removed, and 1,100 were screened. After reading all the full-text reviews, 86 studies were included in the qualitative synthesis. MAS consistently enhanced reaction times and increased conversion, selectivity, yield, and product quality under specific situations. They were used in the synthesis of organic compounds, construction of heterocycles, cross-couplings, nanomaterials, metalorganic frameworks, medicinal synthesis, and green processing. Continuous-flow and energy-based scale-up technologies have demonstrated engineering potential. Discussion: MAS advantages according to dielectric properties, microwave parameters, reactor design, heat and mass transport, and reaction-specific conditions. Industrial translation is hampered by cost, reproducibility, scale-up, reactor standardisation, and poor mechanistic knowledge. Conclusion: MAS is a versatile platform for sustainable response intensification, but industrial adoption requires standardised reporting, confirmed scale-up procedures, realtime process monitoring, and techno-economic and life-cycle evaluation.
Introduction: X60 pipeline steel was widely used in oil and gas pipelines because of its high strength, toughness, ductility, and weldability. Therefore, studying its failure pressure has significant economic and social value. Using X60 pipeline steel as the research object, Finite Element Analysis (FEA) was conducted on two single-defect pipeline models on the external and internal walls. Methods: First, the stress distributions were analyzed. Then, the effects of defect depth, length, width, and diameter-to-thickness ratio on equivalent stress and failure pressure were studied. Finally, a failure pressure formula was developed from the FEA data using MATLAB and verified for accuracy and reliability. Results: For pipelines with external and internal defects, stress is concentrated near the defect, forming a high-risk zone, while stress remains low and uniform away from the defect. Failure pressure decreases as defect depth and length increase, although the effect of length becomes weaker. Defect width has little influence and can be ignored. Under the same conditions, pipelines with external defects are more likely to fail. A higher diameter-to-thickness ratio increases failure pressure, load-bearing capacity, and structural stability. Error analysis shows that the internal defect model provides more accurate predictions than the external defect model, which requires further improvement. Discussion: Based on the effects of defect geometry on equivalent stress and failure pressure, a prediction formula is developed to support the safe operation of oil and gas pipelines. Conclusion: The conclusions drawn provide a certain reference significance for the design and maintenance of oil and gas pipelines.
