Photocatalytic antifouling nanohybrid polysulfone membrane using the synergetic effect of graphene oxide and SiO2 for effective treatment of natural rubber-laden wastewater

Hybrid combination of advanced oxidation process with membrane technology for wastewater treatment: gains and problems

Over the past few decades, significant efforts have been dedicated to advancing technologies for the removal of micropollutants from water. Achieving complete pure water with a single treatment process is challenging and nearly impossible. One promising approach among various alternatives is adopting hybrid technology, which is considered as a win-win technology. It utilizes the advantages of each technique, resulting in the enhancement of wastewater treatment. This pioneering idea is designed to significantly enhance water quality, addressing real-world implementation hurdles, and offer a promising solution to the worldwide issue of water scarcity. This review assesses the merits and drawbacks of the hybrid photocatalytic membrane technology employed in wastewater treatment. Notably, this hybrid process not only improves the membrane filtration capacity and permeates water quality but also enhances the antifouling performance of the membrane. However, it is crucial to acknowledge potential drawbacks, such as membrane structure degradation and photocatalytic activity loss in nanoparticles during the operation period. While improvements in wastewater treatment efficiency are evident, there remains ample room for further enhancements. The review summarizes the future directions and challenges of implementing such an integrated system.

Identification of organic pollutants and heavy metals in natural rubber wastewater and evaluation its phytotoxicity and cytogenotoxicity

The natural rubber industry consumes large volumes of water and annually releases wastewater with rich organic and inorganic loads. This wastewater is allowed for soil irrigation in developing countries. However, the pollutant composition in wastewater and its environmental effects remain unclear. Therefore, we aimed to assess the wastewater's physicochemical parameters, toxic organic pollutants, heavy metals, and phytotoxic and cytogenotoxic. The result revealed that values of comprehensive wastewater parameters were recorded as chemical oxygen demand (187432.1 mg/L), pH (4.23), total nitrogen (1157.1 mg/L), ammonia nitrogen (1113.0 mg/L), total phosphorus (1181.2 mg/L), Zn (593.3 mg/L), Cr (0.6127 mg/L), and Ni (0.2986 mg/L). The organic compounds detected by LC-MS were salbostatin, sirolimus, Gibberellin A34-catabolite, 1-(sn-glycero-3-phospho)-1D-myo-inositol, and methyldiphenylsilane. The toxicity of the identified toxic chemicals and heavy metals was confirmed by onion and mung bean phytotoxicity characterization tests. The wastewater affected the germination of mung bean seeds, reduced or inhibited the growth of onions, and induced various chromosomal aberrations in root apical meristems. Our study shows that the treatment of natural rubber wastewater needs to be improved, and the feasibility of irrigating soil with wastewater needs to be reconsidered.