This comprehensive review explores recent advancements in heavy metal remediation techniques, focusing on the utilization of cellulose–silica composites and tailored surface modification techniques. We examine the synthesis strategies and properties of cellulose–silica adsorbents, highlighting their enhanced adsorption capacities and structural robustness for removing heavy metal pollutants from aqueous environments. The review investigates various surface modification approaches, including thiol functionalization, amino acid grafting, and silane coupling agents, for optimizing the surface chemistry and morphology of cellulose–silica composites. Mechanistic insights into the adsorption processes and kinetics of modified adsorbents are discussed, along with considerations for optimizing adsorption performance under different environmental conditions. This review provides valuable perspectives on the development of effective adsorbent materials for sustainable heavy metal remediation applications.

Biobased biodegradable materials are gaining popularity with increasing public awareness on the negative impacts of conventional plastics on the environment. There is, however, a lack of promising biobased materials suitable for various end‐use applications that are also environmentally safe. Recently, banana sap and banana fibres have been explored as a potential source of organic material as they are abundant, cost‐efficient, and environmentally friendly. In this study, two hybrid bioresins (1) banana sap maleate (BSM) and (2) banana sap maleate + banana fibre (BSMF) were developed, and their material properties and environmental suitability were examined by analysing their physicochemical characterisation and biodegradation testing. We used thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), and Fourier transform infrared (FTIR) spectroscopy for the physicochemical characterisation of BSMF before and after composting and measured carbon dioxide evolved during the biodegradation to calculate biodegradability. SEM analysis also showed a significant disintegration and surface degradation in BSMF compared to BSM and other control materials such as control resin and cellulose. CO₂ mineralization results indicated a potential microbial bioassimilation of the materials under composting conditions. Biodegradability of the BSMF composite, as indicated by CO₂ emission, was 17.6% higher than BSM and other control materials used in this study. The present study provides crucial evidence that the reinforcement of banana fibre into banana sap bioresin composite can significantly improve material properties and enhance biodegradability in the composting conditions. These results are quite promising as they show that, with some tweaking; natural materials can reduce environmental impact of composites and improve material properties for different end‐use applications and involves less exploitation of nonrenewable resources for polymer production. This study also provides an avenue to consider BSMF for carrying out our future life cycle assessment (LCA) and to compare with commercial product’s LCA. In a circular economy approach, characteristics such as durability, environmental toxicity, and recyclability of such materials should be studied and optimised to reduce energy consumption and environmental impact.

This study was carried out to develop a green approach to synthesising sodium cyanide (NaCN) using hydrogen cyanide (HCN) extracted from cassava (Manihot esculenta Crantz) leaves after 120 min of maceration at 30 °C and 45 min of recovery under vacuum at 35–40 °C. The CN^- ion released via autolysis was reacted with the Na⁺ ion following vacuum extraction of the former to produce NaCN by saturating the absorbing sodium hydroxide (NaOH) solution. This specific extraction method avoided direct contact between the cassava leaves homogenate and the absorbing solution. NaCN was crystallised by drying the NaCN slurry at 100 °C in an air oven. A total of 15.70 kg of fresh cassava leaves was needed to produce 32.356 g of NaCN (green-NaCN) (% NaCN yield = 0.21%). The results of X-ray diffraction, attenuated total reflectance–Fourier transform infrared spectroscopy and scanning electron microscopy with energy-dispersive X-ray spectroscopy, show that NaCN was successfully prepared using the proposed method. These spectral techniques showed that the control and green-NaCN contained sodium carbonate impurities. The latter was quantified by the titration experiments and was found to be 0.61% and 2.29% in the control and green-NaCN, respectively. Furthermore, the titration experiments revealed that the residual NaOH content was 1.63% in control NaCN and 4.68% in green-NaCN. The aim of modifying the green synthesis route for producing NaCN from cassava, developed by the Attahdaniel research group in 2013 and 2020, was achieved.

Heavy metals are persistent environmental sources affecting soil quality. Therefore, selecting plant species that can germinate and grow under heavy metal stress is critical for phytoremediation. This study examines the effects of varying concentrations of cadmium (Cd²⁺), lead (Pb²⁺), mercury (Hg²⁺), and arsenic (As³⁺) on germination and growth Trifolium repens, with emphasis on its response to heavy metal stress in South African soils. Seeds with uniform size were sampled and placed in plastic dishes with a layer of towel paper on the bottom and were evenly spaced in each dish on the surface of the towel paper with 5 mL of each metal concentrations. The findings revealed that the metal type and concentration significantly impacted almost all the physiological parameters of Trifolium repens at (P < 0.001). In contrast, there were no significant variations between treatments for the untreated plants at (P > 0.05), indicating that the alterations were primarily related to the experimental setup. There was a consistent inverse relationship between metal concentration and plant performance. The best physiological and germination results were achieved at the lowest treatment level (0.5 mM) whereas plants were extremely affected at 10 mM.