This work includes a synthesis of three types of the activated carbon (AC) from three different positions from the same Iraqi Khestawy date palm. These three positions are the palm fronds (AC1), the date palm seeds (AC2), and the palm fiber (AC3). These three types of AC were synthesized by a physiochemical activation method using the same activator which was H3PO4. These materials were investigated using different techniques such as Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The adsorption activity of the synthesized AC samples was investigated by following the removal of both Bismarck brown G (BBG) and reactive yellow dye 145 (RY145). Both the kinetics of adsorption and the removal percentage of these dyes were investigated from the batch tests in this study. Different reaction parameters and conditions for adsorption processes were investigated. Also an investigation of both Langmuir and Freundlich adsorption isotherms was considered. The different physical properties of these materials were undertaken such as the point zero charges of the synthesized samples (PZCs), the percentage of humidity, and the adsorption capacity also being investigated. The activity of these materials in the removal of BBG from the aqueous solution was as follows:AC1>AC2>AC3.

In this work, we have developed a simple method to prepare cationic chitosan hydrogel with interconnected porous structure using freeze-thaw process and the obtained hydrogel was named FCS hydrogel. Scanning electron microscopy (SEM) imaging revealed that the synthesized hydrogel demonstrated interconnected porous structure in the range of 5-20 µm. We also showed that the FCS hydrogel exhibits pH responsiveness behavior, and demonstrated reversible swelling and de-swelling behaviors maintaining their mechanical stability. We demonstrate that the FCS hydrogel swelling capacity decreased at alkaline pH and increased with a decrease in the pH value. Besides, the FCS hydrogel presented speci c surface area of 78.25 ±8.75 m 2 g −1 , due to the cryogenic treatment of glutaraldehyde cross-linked chitosan hydrogel could increase the surface area and permeability of composite hydrogel and then strongly increasing the adsorption capacity. Subsequently, the FCS monolithic hydrogel tested dyes removal, which provides a high removal e ciency towards anionic dyes including congo red (CR) and sodium uorescein (SFL) dyes. Signi cantly, we show that the FCS hydrogel could be regenerated and reused as an adsorbent for wastewater treatment without signi cant loss of pollutants removal e ciency over a number of adsorption and washing cycles. This study offers a promising environmental friendly and sustainable interconnected porous hydrogel for anionic dye removal from wastewater.

Antimould agents are widely used in different applications, such as specialty paints, building materials, wood preservation and crop protection. However, many antimould agents can be toxic to the environment. This work aims to evaluate the application of copper oxide nanoparticles (CuONPs) surface modified with boronic acid (BA) terminal groups as antimould agents. We developed CuONPs grafted with (3-glycidyloxypropyl) trimethoxysilane (GLYMO), coupled with 4-hydroxyphenylboronic acid (4-HPBA), which provided a strong boost of their action as antimould agents. We studied the antimould action of the 4-HPBA-functionalized CuONPs against two mould species: Aspergillus niger (A. niger) and Penicillium chrysogenum (P. chrysogenum). The cis-diol groups of polysaccharides expressed on the mould cell walls can form reversible covalent bonds with the BA groups attached on the CuONPs surface. This allowed them to bind strongly to the mould surface, resulting in a very substantial boost of their antimould activity, which is not based on electrostatic adhesion, as in the case of bare CuONPs. The impact of these BA-surface functionalized nanoparticles was studied by measuring the growth of the mould colonies versus time. The BA-functionalized CuONPs showed significant antimould action, compared to the untreated mould sample at the same conditions and period of time. These results can be applied for the development of more efficient antimould treatments at a lower concentration of active agent with potentially substantial economic and environmental benefits.

No abstract