Floods frequently threaten villages near the Khazir River’s floodplains, causing crop losses and threatening residential areas. We used flood-related hydrological software, including WMS and HEC-HMS, to study this issue and determine how to reduce the recurrence of flooding. The software can be used to calculate a hydrograph of torrential flows in a river drainage basin and estimate the volume of torrential water and its flow rates on the Earth’s surface. The depth of rain has been evaluated and calculated in the SCS Unit Hydrograph for different return periods of 2, 5, 10, 20, 50, and 100 years. According to our study’s findings, the volume of the river’s drainage basin floods ranged between 29,680 and 2,229,200 m3, and the maximum flow value ranged between 10.4 and 66.4 m3/sec during various reference periods. To analyze and model the flood risks of the Khazir River, the HEC-RAS model was combined with the HEC-GeoRAS extension in ArcGIS. The floods were the focus of two study periods, 2013 and 2018, and were based on the digital elevation model and river discharge during the floods. According to the classification map of the flood depths, the areas of flood risk varied from low to very low (80.31%), medium (16.03%), and high to very high (3.8%). The analysis of the results revealed that the villages closest to the river’s mouth were more affected by the floods than other villages further downstream. HEC-HMS and HEC-RAS have been shown to have a strong correlation in evaluating flood risks and reliably forecasting future floods in the study area.
This study proposed a novel and low-cost adsorbent prepared from dredging sediment (DSD) for effective removal of dye in aqueous solutions. The adsorption efficiency and behavior of the DSD adsorbent toward the crystal violet (CV), a cationic dye, were investigated via batch experiments. The results showed that DSD samples contain mainly clay minerals (illite and kaolinite) and other mineral phases. In addition, DSD is a mesoporous material (Vmesopore = 94.4%), and it exhibits a relatively high surface area (~39.1 m2/g). Adsorption experiments showed that the solution’s pH slightly affects the adsorption process, and a pH of 11 gave a maximum capacity of 27.2 mg/g. The kinetic data of CV dye adsorption is well described by the pseudo–second-order and the Avrami models. The Langmuir and Liu isotherm models provide the best fit for the adsorption equilibrium data. The monolayer adsorption capacity of Langmuir reached 183.6, 198.0, and 243.6 mg/g at 293, 308, and 323 K, respectively. It was also found that the adsorption process was spontaneous (−ΔG°), exothermic (−∆H°), and increased the randomness (+∆S°) during the adsorption operation. The primary mechanisms in CV dye adsorption were ion exchange and pore filling, whereas electrostatic attraction was a minor contribution. In addition, three steps involving intraparticle diffusion occur at the same time to control the adsorption process. The results of this study highlight the excellent efficiency of DSD material as an ecofriendly sorbent for toxic dyes from water media.
Finding eco-friendly products that are beneficial to the environment and serve as tools for sustainable development is a contemporary challenge. This work illustrates the recovery of bio-waste-based materials, which not only improve the hygrothermal properties of gypsum but also promote the paper and wood recycling processes in a circular economy approach. The samples were subjected to tests for density, water absorption, ultrasonic pulse velocity, flexural strength, compressive strength, and thermophysical property characterization. A statistical analysis of variance was used to study the impact of waste on the physico-mechanical behavior of gypsum, leading to the development of predictive models that can be used to predict and optimize the performance of bio-composites in various applications. The results revealed a reduction in mechanical strength with the addition of waste, but the samples still exhibit superior insulation properties, surpassing commonly used standard boards. By adding ouate and wood wastes to a mass of 20% in its natural state, the gypsum becomes lighter and acts as a better insulator with a reduced density, thermal conductivity, and ultrasound velocity of up to 50%, 57%, and 83%, respectively. These findings show the significant implication of reducing environmental impacts while contributing to the promotion of sustainable building practices, both in new construction projects and in building renovations.
Interstratified illite–smectite clay samples from Tunisia have been used in order to prepare Al, Zr and Zr–Al-pillared clays. Several Al/metal, OH/metal ratios were used in order to investigate the effect on the chemical and physical properties, specifically the point of zero charge (PZC) of the synthesized pillared clays. The structure of the pillared materials is studied by XRD and cationic exchange capacity. The textural property is investigated by the nitrogen adsorption/desorption method. The acid–base chemistry “surface acidity” of these products was analysed by using mass and potentiometric titration in order to determine the PZC and the equilibrium constants (pKa) of each sample. The resulting materials exhibited basal spacings in the range of 17.4–20.5Å, with high surface areas (134–199m2g−1). Titration curves obtained by acid–base potentiometric titration for the starting material showed an indistinct cross-over point at about pH=7.3, whereas in the case of pillared samples, points were observed at the acidic region between 4 and 6. In addition, the calculated pKas values of pillared clays show a shifting to the acidic values compared to the untreated sample
Slow kinetics is one of the capital issues of photocatalytic technology because of its heterogeneous nature, which involves multi-step processes. Herein, we show that the simple modification of the sol-gel-based TiO2-smectite composite by hexadecyltrimethylammonium bromide (HDTMA) significantly boosts adsorption and photocatalytic efficient sol-gel-based light towards the removal of diclofenac from water. Three photocatalysts were prepared, including TiO2, TiO2-smectite, and HDTMA-TiO2-smectite. The materials were characterized to understand the surface interaction and crystal characteristics. In terms of photoactivity, it was found that the addition of HDTMA to TiO2-smectite improved the removal rate by twice. HDTMA changes the functional groups to TiO2-smectite composite allowing enhanced adsorption and photoactivity through the so-called Adsorb and Shuttle process. The recycling tests show that HDTMA-TiO2-smectite can be used up to four times with good performance. This modification approach could intensify the removal of pollutants from water instead of using complicated and costly techniques.