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Ensuring the safety of rural drinking water is a basic component of poverty alleviation in China. Studying the strategy for ensuring drinking water safety in areas that were lifted out of poverty is important for consolidating poverty alleviation achievements and promoting rural revitalization in China. In this article, we study the current situation and problems of rural drinking water in poverty alleviation areas, analyze the causes of the problems, and propose strategic objectives and pathways from the aspects of engineering, policy, and mechanism. To guarantee the safety supply of rural drinking water in poverty alleviation areas, we suggest that the drinking water safety policies in these areas should remain stable and constant, the sanitary standards of drinking water in rural areas should be optimized to meet those in urban areas, and a long-term policy focusing on water price should be established for rural water supply.

Bimetallic oxides composites have received an increasing attention as promising adsorbents for aqueous phosphate (P) removal in recent years. In this study, a novel magnetic composite MZLCO was prepared by hybridizing amorphous Zr-La (carbonate) oxides (ZLCO) with nano-Fe 3 O 4 through a one-pot solvothermal method for efficient phosphate adsorption. Our optimum sample of MZLCO-45 exhibited a high Langmuir maximum adsorption capacity of 96.16 mg P/g and performed well even at low phosphate concentration. The phosphate adsorption kinetics by MZLCO-45 fitted well with the pseudo-second-order model, and the adsorption capacity could reach 79% of the ultimate value within the first 60 min. The phosphate adsorption process was highly pH-dependent, and MZLCO-45 performed well over a wide pH range of 2.0-8.0. Moreover, MZLCO-45 showed a strong selectivity to phosphate in the presence of competing ions (Cl - , NO 3 - , SO 4 2- , HCO 3 - , Ca 2+ , and Mg 2+ ) and a good reusability using the eluent of NaOH/NaCl mixture, then 64% adsorption capacity remained after ten recycles. The initial 2.0 mg P/L in municipal wastewater and surface water could be efficiently reduced to below 0.1mg P/L by 0.07 g/L MZLCO-45, and the phosphate removal efficiencies were 95.7% and 96.21%, respectively. Phosphate adsorption mechanisms by MZLCO-45 could be attributed to electrostatic attraction and the inner-sphere complexation via ligand exchange forming Zr/La-O-P, -OH and CO 3 2- groups on MZLCO-45 surface played important roles in the ligand exchange process. The existence of oxygen vacancies could accelerate the phosphate absorption rate of the MZLCO-45 composites., (Copyright © 2022. Published by Elsevier B.V.)

Cationic hydrogels have received great attention to control eutrophication and recycle phosphate. In this study, a type of La(OH) 3 loaded magnetic MAPTAC-based cationic hydrogel (La(OH) 3 @MMCH) was developed as a potential adsorbent for enhanced phosphate removal from aqueous environment. La(OH) 3 @MMCH exhibited high adsorption capacity of 105.72±5.99 mg P/g, and reached equilibrium within 2 hr. La(OH) 3 @MMCH could perform effectively in a wide pH range from 3.0 to 9.0 and in the presence of coexisting ions (including SO 4 2- , Cl - , NO 3 - , HCO 3 - , SiO 4 4- and HA). The adsorption-desorption experiment indicated that La(OH) 3 @MMCH could be easily regenerated by using NaOH-NaCl as the desorption agent, and 73.3% adsorption capacity remained after five cycles. Moreover, La(OH) 3 @MMCH was employed to treat surface water with phosphate concentration of 1.90  mg/L and showed great removal efficiency of 95.21%. Actually, MMCH showed high surface charge density of 34.38-59.38 meq/kg in the pH range from 3.0 to 11.0 and great swelling ratio of 3014.57% within 24 h, indicating that MMCH could produce the enhanced Donnan membrane effect to pre-permeate phosphate. Furthermore, the bifunctional structure of La(OH) 3 @MMCH enabled it to capture phosphate through electrostatic attraction and ligand exchange. All the results prove that La(OH) 3 @MMCH is a promising adsorbent for eutrophication control and phosphate recovery., (Copyright © 2021. Published by Elsevier B.V.)