Precise control over polymer molecular architecture is critical for the development of advanced functional materials with tailored properties. Reversible Deactivation Radical Polymerization (RDRP) techniques enable the synthesis of well-defined polymers under mild and scalable conditions, making them highly suitable for industrial applications. Among these methods, Cu(0)-mediated polymerization stands out for its use of a reusable copper-wire catalyst, low transition-metal concentrations, and ambient temperature operation. These features significantly reduce purification costs, energy consumption, and environmental impact, aligning with the principles of green chemistry.

Notably, the polymerization of methyl methacrylate (MMA) proceeds efficiently in Cyrene®, a bio-based, non-toxic solvent derived from cellulose, making it a promising alternative to conventional organic solvents. High levels of monomer conversion and polydispersity indices below 1.5 were achieved under ambient conditions, confirming the system’s efficiency.

In this study, we investigated the Cu(0)-mediated polymerization of MMA in Cyrene®, focusing on the estimation of kinetic parameters based on experimental data generated in our laboratory. A mathematical model was developed using the well-established method of moments, allowing for simulation of the polymerization kinetics. The model showed strong agreement with experimental results, supporting its predictive capability.

This work contributes to the development of more sustainable polymer-manufacturing strategies and demonstrates the value of kinetic modeling as a tool for guiding the process optimization and industrial-scale implementation of green polymerization techniques.

The large-scale production of various synthetic dyes has significantly contributed to the discharge of large volumes of wastewater into the environment. It is estimated that approximately 105,000 tons of dyes from the textile industry are released annually, severely compromising water quality [1]. In this context, the present study evaluates the adsorption potential of agricultural and timber residues—including Tectona grandis sawdust, baobab sawdust, coconut shells, cork bark, almond shells, and olive pits—for the removal of methylene blue (MB) from aqueous solutions. All materials were used without prior thermal treatment. Kinetic experiments were carried out at 298 K and pH 6, using 25.0 mg of adsorbent added to 25.0 mL of MB solution (20 mg L⁻¹), agitated at 20 rpm for up to 168 hours. Adsorption isotherms were obtained using MB concentrations ranging from 0 to 250 mg L⁻¹, with agitation under the same conditions for 24 hours. The influence of pH (3–11) was assessed by adjusting the pH with 0.1 mol L⁻¹ HCl or NaOH and following the same adsorption procedure. The natural adsorbents demonstrated good performance in removing methylene blue from aqueous solutions. Among the tested agricultural wastes, coconut shells exhibited the highest MB removal capacity, reaching a maximum of 106 mg g⁻¹ at 298 K and pH 6. These findings support the use of agricultural and timber sector residues as efficient and sustainable alternatives to conventional materials such as activated carbons. This approach aligns with circular economy principles, promoting waste valorization and reducing environmental impacts.

The growing accumulation of scrap tyres in Nigeria poses significant environmental and public health risks due to improper disposal methods such as open burning and illegal dumping. In response to this challenge, pyrolysis has emerged as a sustainable waste management and resource recovery technique capable of converting scrap tyres into valuable products such as pyro-diesel, char, and steel wire. However, the economic viability and energy performance of pyrolysis systems remain largely unexplored in the Nigerian context. This study addresses this gap by evaluating the techno-economic feasibility and energy efficiency of scrap tyre valorization via pyrolysis under two configurations: (i) a standalone pyrolysis plant (Scenario 2) and (ii) a pyrolysis plant integrated with power generation (Scenario 1). Process simulations were carried out using Aspen PLUS V12, while cost estimations were conducted with the Aspen Process Economic Analyzer. Both configurations were assessed for a processing capacity of 20 tons per hour. The process yields included pyro-diesel (39.13%), char (35.62%), steel wire (15.04%), pyrolytic gas (7.90%), and heavy oil (2.30%). Energy analysis showed that Scenario 2 attained a higher energy efficiency of 79.72%, compared to 74.76% in Scenario 1. Nonetheless, Scenario 1 demonstrated superior economic performance, with a Net Present Value (NPV) of USD 28.65 million (NGN 42.97 billion) and an Internal Rate of Return (IRR) of 34.48%, despite its higher capital investment. These findings highlight a critical trade-off between energy efficiency and profitability. While standalone pyrolysis systems are more energy efficient, integrating power generation significantly enhances financial returns—making it a more attractive model for large-scale application in Nigeria’s waste-to-energy landscape.

Nitroaromatic compounds, such as 1,3-dinitrobenzene (DNB), are widely used in the manufacture of dyes, explosives, and pesticides and are frequently detected as persistent pollutants in industrial wastewater. DNB is classified as a toxic and potentially carcinogenic compound; it can be absorbed through inhalation, ingestion, or skin contact and is known to affect the central nervous system. Due to its stability in aqueous media and resistance to biodegradation, DNB poses a serious threat to aquatic ecosystems and human health, emphasizing the need for sensitive and efficient detection methods.

In this study, we report a fast, simple, and low-cost synthesis of a bimetallic CuAg/rGO (copper–silver on reduced graphene oxide) nanocomposite intended for the electrochemical detection of DNB in water samples. Material characterization was performed using scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM/EDX) and transmission electron microscopy (TEM), confirming the formation of Cu and Ag nanoparticles homogeneously distributed over the rGO surface and embedded within its layered structure.

The electrochemical activity of a glassy carbon electrode modified with CuAg/rGO was examined by CV. The modified electrode exhibited a distinct reduction peak for DNB at ~ –0.6 V vs. a saturated calomel electrode (SCE). The limit of detection (LOD) was determined to be 2.21 µM within a linear range of 0–50 µM.

These results demonstrate that the CuAg/rGO-modified electrode provides a promising low cost and efficient electrochemical sensing platform for the rapid detection of nitroaromatic pollutants, with potential application in routine environmental monitoring.

This research investigates the adsorption of methylene blue dye. Methylene blue is a common cationic dye used in various industries, and its presence in wastewater poses significant environmental and health concerns. Traditional methods for dye removal can be expensive and generate secondary pollutants. Mango leaf powder proves to be a cost-effective and environmentally friendly adsorbent for the removal of methylene blue (MB) dye from aqueous solutions. Characterization was performed through Scanning Electron Microscopy (SEM) for the morphology of the mango leaf powder; Fourier Transform Infrared Spectroscopy (FTIR) and X-ray Diffraction (XRD) for the crystallinity of the mango leaf powder; and Thermogravimetric Analysis (TGA) for the thermal stability of the mango leaf powder. Batch adsorption experiments were conducted to evaluate the efficiency of mango leaf powder in removing methylene blue from aqueous solutions. The study employed both Langmuir and Freundlich isotherms to analyze the adsorption data, revealing a higher correlation coefficient for the Freundlich model (R² = 0.932) compared to the Langmuir model (R² = 0.8864). Kinetic studies indicated that the pseudo-second-order model provided a better fit for the adsorption process (R² = 0.8288). Thermodynamic parameters were calculated, showing a Gibbs free energy change (ΔG) of -0.364 × 10⁻³ kJ/mol, an enthalpy change (ΔH) of -0.521 × 10⁻³ kJ/mol, and an entropy change (ΔS) of 2.233 J/mol·K, indicating that the adsorption process is spontaneous and exothermic in nature. Furthermore, a reusability study demonstrated that mango leaf powder can be effectively reused across three cycles without significant loss in adsorption capacity, affirming its potential as a sustainable biosorbent for wastewater treatment applications.

Globally, invasive alien species (IAS) present substantial socio-economic and environmental challenges, typically forming dense thickets and stands, which are largely accessible, unexploited, and underutilised sources of biomass. Therefore, this study examines the bioenergy potential of three IAS with woody stems, Combretum malabaricum (CM), Mimosa pigra (MP), and Ipomoea carnea (IC), as sustainable raw materials for charcoal production via carbonisation. It also examines the physico-chemical and energy properties of the resulting charcoals, thus presenting a sustainable valorisation approach. Carbonisation was conducted in a muffle furnace at a temperature of 600 °C and with a 30-minute residence time, followed by charcoal characterisation. Next, the charcoals were characterised to gravimetrically and computationally determine their mass yield (MY), higher heating value (HHV), and energy yield (EY). The results revealed that IAS charcoals have promising properties based on these analyses. The MYs were 21.77%, 27.18%, and 26.65% for CM, MP, and IC, respectively. Furthermore, the HHV values were 27.16 MJ/kg, 26.65 MJ/kg, and 26.70 MJ/kg, whereas the EY values were 5.91%, 7.24%, and 7.12% for CM, MP, and IC, respectively. The HHV indicates that the charcoals synthesised from the IAS are promising alternatives to traditional tree-type sources, presenting solutions to the challenges posed by felling trees, deforestation, and biodiversity linked to charcoal production. Additionally, the results underscore the twin merits of utilising these abundant and underutilised IAS, which would contribute to weed control, environmental management, and renewable/sustainable energy generation. Future research will concentrate on the optimisation of the carbonisation parameters and product charcoals and explore specialised applications.

Globally, the spread of invasive plant species (IPS) poses substantial ecological and economic problems. Although considered weeds by farmers, such plants are woody-stemmed and lignocellulosic in nature, which, in addition to their abundance and underutilisation, makes them suitable for bioenergy recovery and utilisation. Therefore, the current study seeks to examine the bioenergy potentials of three abundant, problematic, and underutilised IPS, Mesosphaerum suaveolens (MS), Calotropis procera (CP), and Chromolaena odorata (CO), as sustainable raw materials for charcoal production through carbonisation. Additionally, the physico-chemical and energy characteristics of the IPS charcoals are critically examined to present a comprehensive strategy for effective biomass resource management and renewable material/energy production in Nigeria. The carbonisation process was conducted in a muffle furnace at a temperature of 600°C and with a residence time of 30 minutes. On completion, the biochars were characterised to examine the impact of the process and plant structure on the biochar mass yield (MY), mass loss (ML), higher heating value (HHV), and energy yield (EY). The results revealed that the IPS charcoals display favourable characteristics. Notably, the MY for MS, CP, and CO ranged from 23.33% to 39.20%, whereas the ML ranged from 60.80% to76.67%. In contrast, the HHV and EY ranged from 25.53 MJ/kg to 27.01 MJ/kg and 6.30 MJ to 10.01 MJ, respectively. The highest ML and HHV were observed from MS, whereas the highest MY and EY were observed for CP. The high values of HHV and EY highlight not only the solid biofuel potential of these abundant, underutilised, and woody IPS but also present a sustainable approach to their ecological management and sustainable energy production. Future studies could critically explore the optimisation of the carbonisation parameters and wider applications of the IPS charcoals.

Exploiting the circular economy has been a vital resource utilization and energy recovery strategy. This study examined the influence of pyrolytic temperature on the chemical, physical and morphological properties of biochar derived from waste biomass and recommended its suitability for environmental application and energy production. The biochar synthesis was performed by thermal degradation of green pea pods in the presence of Na₂CO₃ catalyst at temperatures of (300-800 ^oC in 100 ^oC intervals). Thephysicochemical characteristics and morphological structures of the produced char were evaluated, including mineral composition, carbon content, functional groups and morphological structures, using basic characterization techniques. The findings indicated that the biochar's specific surface area increased from 0.6836 m²/g to a maximum of 683.2 m²/g, whereas the mean pore diameter decreased from 161.67 nm at 300 ^oC to 1.4774 nm at 600 ^oC. And later on, it rose to 2.1778 nm at 800 ^oC. The increase in pyrolysis temperature demonstrated a positive relationship with the biochar's carbonization degree, aromatization and stability. On the other hand, yield, oxygenated functional groups, nitrogen and oxygen reduced, exhibiting a negative relationship. Moreover, the produced biochar materials had improved higher heating value (HHV) of (16.56 - 23.6 MJ/kg) in comparison to 15.50 MJ in the feedstock. Thus, biochar from waste peels at various pyrolysis temperatures can be effective in the recovery of energy, decontamination of organic and inorganic pollutants in wastewater and agronomic nourishment.

This study investigates the potential of waste gypsum (WG) as a sustainable substitute for natural gypsum (NG) in the production of ordinary Portland cement (OPC). The WG used was collected from construction site molds and originated from the hydration of Tunisian plaster. Cement samples were prepared by grinding clinker with 3 to 5 wt% of either WG or NG using a laboratory planetary ball mill (Powteq MG 200), producing waste gypsum cement (CMWG) and natural gypsum cement (CMNG), respectively.

To evaluate the suitability of WG, both gypsum types were characterized using X-ray diffraction (XRD), X-ray fluorescence (XRF), and differential scanning calorimetry/thermogravimetric analysis (DSC/TG). XRD results showed that NG consisted mainly of gypsum dihydrate, while WG contained a mixture of dihydrate and hemihydrate phases. Thermal analysis further confirmed a significantly higher hemihydrate content in WG. These differences could influence cement hydration and setting behavior.

Despite the mineralogical differences, mechanical testing revealed that the flexural and compressive strengths of CMWG were comparable to those of CMNG at all tested ages. This indicates that replacing natural gypsum with waste gypsum does not adversely affect the mechanical performance of the resulting cement.

Overall, the results demonstrate that WG, a construction waste byproduct, can be effectively utilized as a setting regulator in OPC. This substitution contributes to resource conservation and waste valorization without compromising the cement’s structural integrity, making it a promising step toward more sustainable construction materials.

Invasive plant species (IPS) like Senna obtusifolia (SO), Flueggea virosa (FV), and Ficus aurea (FA) pose environmental and economic problems in Nigeria. Notably, IPS have adverse impacts on native flora, biodiversity, and ecosystems, whilst weakening agricultural productivity and land use effectiveness. However, such plants are characterised by high lignocellulosic content, woody stems, and rapid growth rates, which make them abundant, accessible feedstock candidates for bioenergy recovery and utilisation. Therefore, this study explores the charcoal production potential of SO, FV, and FA through carbonisation. The process was accomplished by heating the samples at a temperature of 600 °C and 30 minutes residence time, followed by cooling and characterisation of the charcoal mass yield (MY), mass loss (ML), higher heating value (HHV), and energy yield (EY). The results showed that the MY and ML ranged from 21.55% to 29.81%, and 70.19% to 78.45%, respectively, whereas the HHV and EY ranged from 26.41 MJ/kg to 27.18 MJ/kg, and 5.86 MJ to 7.87 MJ, respectively, which indicate adequate results for the sustainable production of charcoals from SO, FV, and FA. The highest HHV and ML were observed in FA, whereas the highest ML and EY were observed in FV. The SO sample revealed intermediate values for most parameters examined in the study. The results demonstrated that carbonisation of such plentiful, yet underutilised plant species is a practical management approach and route for sustainable solid fuels production. Lastly, this strategy helps to ensure environmentally sustainable ecosystem protection and promotes the sustainable livelihoods of locals who can tap into such initiatives.