The overall cost and efficiency of an adsorbent material is a major issue in deriving a sorbent into commercial markets. In this study, efforts have been directed to produce adsorption-capable zeolites from the dispensable product of coal power plants, i.e., coal fly ash (CFA). In addition, coal mining water (CW) was used as a direct hydrothermal solvent. The mine water from China's coal mines was used in this experiment to substitute tap water (TP) for synthesizing zeolite from C-type fly ashes with different crystallization temperatures (45 to 95 °C). Here, CW led to the formation of X-type and A-type zeolites of comparable size. Regarding the proper utilization of waste products, i.e., coal fly ash and mine water, the study paves a simple yet extremely cost-effective approach to synthesize workable zeolitic materials for adsorption purposes. The detailed characterization justified the use of CW as a better solvent than TP to prepare zeolites based on their better granular size and fewer carbon impurities. The prepared zeolites were later used as an adsorbent for the trace removal of ceftazidime (CAZ), taken as a model pharmaceutical pollutant. The zeolites prepared using CW realised a higher adsorption capacity of 80 mg g⁻¹ during 20 min of agitation time. The pH, concentration, and external salt effects were also studied to achieve maximum removal efficiency. In general, the proposed approach enables the production of affordable yet efficient zeolite-based adsorbent materials without consuming any toxic and expensive reagents for practical application in environmental remediations.

Low-calcium fly ash (LC-F) and high-calcium fly ash (HC-F) were used to synthesize corresponding zeolites (LC-Z and HC-Z), then for adsorption of Se(IV) in water. The results showed that c zeolites can effectively adsorb Se(IV). The optimal adsorption conditions were set at contact time = 360 min; pH = 2.0; the amount of adsorbent = 5.0 g·L⁻¹; temperature = 25 °C; initial Se(IV) concentration = 10 mg·L⁻¹. The removal efficiency of HC-Z was higher than the LC-Z after it had fully reacted because the specific surface area (SSA) of HC-Z was higher than LC-Z. The adsorption kinetics model of Se(IV) uptake by HC-Z followed the pseudo-second-order model. The Freundlich isotherm model agreed better with the equilibrium data for HC-Z and LC-Z. The maximum Se(IV) adsorption capacity was 4.16 mg/g for the HC-Z and 3.93 mg/g for the LC-Z. For the coexisting anions, SO₄^2- barely affected Se(IV) removal, while PO₄^3- significant affected it. Regenerated zeolites still had high capacity for Se(IV) removal. In conclusion, zeolites synthesized from fly ashes are a promising material for adsorbing Se(IV) from wastewater, and selenium-loaded zeolite has the potential to be used as a Se fertilizer to release selenium in Se-deficient areas.

Root anchoring provides nonnegligible assistance to prevent soil erosion and stabilize slopes. The anchoring ability of plants suffers a tremendous impact from the soil conditions and the root characteristics. To reveal the root reinforcement effect, a group of pullout tests was conducted on five different tree root systems (Pinus tabulaeformis, Betula platyphylla, Larix gmelinii, Quercus mongolica, and Ulmus pumila) with different soil moisture contents and soil dry weights. The results indicate that the root property (species, diameter, and tensile strength) and soil condition (water content 9.72%, 12.72%, 15.72%, 18.72%, and dry weight 1.32 g/cm³, 1.42 g/cm³, 1.52 g/cm³) had a significant effect on the anchoring effect of the soil. The anchoring effect is more obvious for the roots with a larger diameter and higher tensile strength. With the increase in the soil water content and the dry weight, the root system is more prone to failure but the root anchoring effect of soil with an optimum soil water content performs the best. Among the five different tree species, Pinus tabulaeformis roots were the least effective in anchoring the soil and Betula platyphylla roots performed the best.