This paper presents the results of using cold plasma to treat surface water for domestic use purpose. Experimental results showed that cold plasma was an effective method for destroying bacteria in water. After treatment with cold plasma, concentration of coliform and Escherichia coli dramatically reduced. Besides, cold plasma significantly removed water odor, increased dissolved oxygen and decreased the concentration of chemical oxygen demand. However, cold plasma significantly raised the concentration of nitrite and nitrate. Other disadvantages of treating with cold plasma were conductivity increase and pH reduction. Pretreatment steps of coagulation, flocculation, sedimentation and sand filtration followed by disinfection with cold plasma exhibited a high efficiency in surface water treatment. All parameters of surface water after treatment by using the prototype satisfied with the allowance standard of domestic water quality.

The bimetallic Zn/Co zeolitic imidazole frameworks (ZnCo-ZIFs) were successfully synthesized by a simple solvothermal method at room temperature. Silver elements were afterward doped onto the bimetallic frameworks to form Ag/ZnCo-ZIFs via a facile impregnation method in acetone solvent. The as-synthesized material was used as a heterogeneous catalyst for the removal reaction of Congo red (CR) and malachite green (MG) in the presence of hydrogen peroxide (H2O2). Effects of catalyst dosage, H2O2 concentration, initial concentration of the contaminants, reaction temperature, and reaction time were conducted in this work. The results showed that more than 94% and 98% removal of CR and MG were, respectively, achieved within 45 and 30 min. The presence of Ag also enhanced the removal efficiency of CR and MG. The main mechanism of removal reaction of the organic contaminants could be oxidation via hydroxyl radicals. Moreover, the catalytic activity of the material remained over 90% after four recycling cycles. Due to the efficient reactivity as well as high stability, Ag/ZnCo-ZIFs can be a potential heterogeneous catalyst to remove hazardous dyes from aqueous solution.

A cerium‐based metal‐organic framework, namely MOF‐589, was synthesized using benzoimidephenanthroline tetracarboxylic acid (H4BIPA‐TC) as an organic linker. Full characterization including single‐crystal and powder X‐ray diffraction analysis, thermogravimetrical analysis, scanning electron microscopy, and N2 adsorption measurements at low pressure and 77 K were carried out. The material was employed as an efficient heterogeneous catalyst for decomposition of methylene blue (MB) dye (40 ppm) in the presence of H2O2 in 15 minutes. Interestingly, comparison studies showed that the activity of MOF 589 was higher than that of other iron‐based heterogeneous and cerium‐based catalysts. Further experiments to clarify the MOF 589 activity indicated that the BIPA‐TC linker might have an important impact through a cooperative effect on the metal cluster. Control studies confirmed that the presence of catalyst was necessary for the reaction to occur and the catalyst recyclability. In particular, catalysis from leached cerium in the reaction filtrate is unlikely and the solid material could be reused at least eight times without a remarkable loss in activity.

Pesticide containing wastewater is concerned due to their toxicity to human health and the environment, and therefore, is attracted much attention by public communities and scientists. This type of wastewater can be treated by conventional treatment methods including physical, chemical, biological methods and so on. Unfortunately, the efficiency of these methods are mostly undesired as expectation because they cannot completely remove toxic organic pollutants from wastewater. In this study, an experiment on laboratory scale model of cold plasma technology, a well-known water treatment method in recent decades, was performed to assess its efficiency on removing pesticide fenobucarb from the wastewater. Furthermore, another experiment on laboratory scale model of the cold plasma combined with coagulation/flocculation and ion exchange process was implemented to assess the efficiency of these combination and each process as well on treatment of pesticide containing wastewater. Experimental results demonstrated that the model of technologies combined was high effective in removing organic pollutants from wastewater. However, the specific efficiency of cold plasma technology in treating wastewater was low. Treatment time, energy supply and wastewater characteristics are the factors which are necessary to be further studied for cold plasma technology application.

This chapter provides synthesis and recommendations concerning the biosafety of introducing Bt cotton into Vietnam. The following aspects are discussed: problem formulation and options assessment for environmental risk assessment, Bt cotton transgene locus structure and expression, nontarget and biodiversity risk assessment, evaluation of the possibility and consequences of gene flow from Bt cotton, and resistance risk assessment and management for Bt cotton in Vietnam.