The aim of this research was to determine whether water hyacinth can be used to remove heavy metals, such as cadmium, arsenic, lead, zinc, and copper, from industrial wastewater. Investigations of the pollution removal or prevention potential of aquatic macrophytes, such as heavy metal bio-indicators in aquatic habitats, can prove to be advanced field studies. Water hyacinth is one of the aquatic plant species that has been effectively utilized for the treatment of wastewater. It is extremely effective in removing stains, suspended solids, BOD, organic matter, and heavy metals. This research focused on the use of water hyacinth to treat wastewater from heavy metals. Water hyacinths can grow in sewage, absorbing and digesting contaminants and transforming sewage effluents into comparatively clean water in the process. As a result, the plants have the potential to be used as natural water purification systems at a fraction of the cost of a standard sewage treatment facility. The experiment was performed using healthy, young, and acclimatized water hyacinths. Containment water with a cadmium concentration of 0.5 mg/L, arsenic concentration of 0.5 mg/L, lead concentration of 2 mg/L, zinc concentration of 5 mg/L, and copper concentration of 5 mg/L was added to five different polyethylene pots with 100 g of water hyacinth in each pot. After 30 days, the removal efficiency for heavy metals (Cd, As, Pb, Zn, and Cu) reached 59–92%, and the results were within the permitted limits according to the National Technical Regulation on Industrial Wastewater in Vietnam. Based on this information, it is possible to deduce that water hyacinth can be utilized to remove cadmium, arsenic, lead, zinc, and copper from industrial wastewater effluents efficiently.

In this research, the magnetic Fe₃O₄/zeolite NaA nanocomposite (Fe₃O₄/ZA), Fe₃O₄ nanoparticles, and zeolite NaA have been synthesized by facile hydrothermal methods for adsorption removal of methylene blue from aqueous solution. The as-synthesized Fe₃O₄/ZA nanocomposite was characterized by X-ray diffraction (XRD), MicroRaman analysis, Fourier-transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), energy-dispersive X-ray (EDX) spectroscopy, X-ray fluorescence (XRF), N₂ adsorption isotherms (BET), and UV-VIS analysis. The results show that with a small weight loading of Fe₃O₄, the 3.3 Fe₃O₄/ZA sample exhibits a high adsorption capacity (40.36mg·g⁻¹) and removal efficiency (96.8) compared to that of the zeolite NaA (32.99mg·g⁻¹ and 79.11, respectively). Interestingly, the removal efficiency and the adsorption capacity increase rapidly with the increase of adsorption time (1060 minutes) and Fe₃O₄ loading (3.39.3 wt.) in the Fe₃O₄/ZA composition. The adsorption mechanism of MB molecules of the Fe₃O₄/ZA can be addressed at the combination of the interaction between active sites on the surfaces and edges of the invert spinel ferrite Fe₃O₄ nanoparticles and zeolite NaA with MB molecules. Our approach provides a simple, efficient, and scalable synthesis process that render practical applications of the magnetic Fe₃O₄/ZA nanocomposite as a lower-cost adsorbent for wastewater treatment.

Aquaponics is not a new technology including a wide variety of systems, but the interest has grown rapidly in recent years, especially in developing countries. Each system has different types and levels of costs and interest. Aquaponics can be implemented using low-cost materials making it more attractive farmers to diversify their incomes. This article examined the profitability of applied aquaponics in thoroughly reused, recycle local materials and the local species. Three sources of data were considered for the study: (1) commercial local species farms, (2) applied aquaponics farms and (3) published research. The first analysis compares the economics of local farms, traditional aquaponics and applied aquaponics systems under similar operations. Results suggest that the traditional aquaponics system requires higher investment and operating cost compared with the applied aquaponics system and local farms. The second analysis constructed on the aquaponics production of fish and plants as well as the returns. The study found that at the small scale of 1-year operation, applied aquaponics is the most profitable model ($1991.34) at 36 percentage of interest. It is more advantage to develop the economic, social by building environmental sustainability of agriculture to maximize food production through applied aquaponics. The economic efficiency of applied aquaponics in using multiple use of resources, primarily water and nutrients, and recycle certain infrastructural, management and labor costs will keep the aquaponics lasting and expanding to social life.