Nano-adsorbents obtained from walnut and almond shells for the effective removal of aflatoxin B1
In the present study, new nano-adsorbents were prepared from the walnut (WSN) and almond (ASN) shells for the sequestering of aflatoxin B1 (AFB1) contamination. The nano-adsorbents were characterized via SEM, EDS, XRD, and FTIR spectroscopy techniques to discover valuable data about the morphology, surface, and chemical configuration of the nano-adsorbents. The adsorption process was further optimized by altering the biosorbent dosage, AFB1 concentration, pH, time, and temperature. Among the tested biosorbents, the WSN and ANS presented a significant removal of AFB1 compared with the walnut and almond shell powders (WSP and ASP). The maximum removal using WSN and ASN was achieved as 93.70% and 83.81% using 10 mg/mL of nano-adsorbent, pH 5.0 at 45 °C for 45 min. Langmuir was the best fitting model for each adsorption data with adsorption capacities of WSP, ASP, WSN, and ASN were 47.6, 36.1, 176.3, and 161.1 mg/g, respectively, with a leading monolayer form adsorption. Kinetic data followed the pseudo-second-order with fast AFB1 uptake. However, thermodynamics studies indicated the spontaneity and endothermic nature of the adsorption process. Furthermore, no significant decline in AFB1 adsorption was recorded after reusability up to five times. The production of nano-adsorbents in this study offers the possibility of dropping the cost of production, controlling agro-waste, and reducing toxins and other organic materials. Finally, the adsorption presentation confirmed the ability of this novel, cost-effective, environment-friendly, and non-toxic biosorbent to remove AFB1 effectively.
https://doi.org/10.1007/s13399-025-06590-w
The production of environmentally friendly building materials out of recycling walnut shell waste: a brief review
Agricultural waste is one of the wastes with a significant value in producing environmentally friendly materials that can be used in the construction sector. This review paper focuses on the potential uses of walnut shell in some building materials. Walnut shell is a type of agricultural waste that can be converted from waste into usable materials by incorporating it into the manufacture of some building materials to achieve sustainability in the construction industry. Recently, walnut waste has drawn the attention of researchers to generate building-friendly materials to boost sustainability in the construction field. In this sense, the walnut shell’s low specific gravity makes it a viable material, as a cheap agricultural waste product, for the development of building materials. According to a survey of the literature, walnut shells can be utilized in the production of structural elements and thermal insulating concrete, up to 30% and 50% as particles respectively. https://doi.org/10.1007/s13399-023-04760-2