Pakpong Sriprasert is lecturer of Environmental Technology, Faculty of Environment andrnResource Studies at Mahasarakham University, Maha Sarakham, Thailand. Her researchrncurrently focus on pollution control and environmental sustainability, especially, the processrnof water pollution and treatment of both domestic and industrial wastewater. She specializesrnin wastewater treatment technologies including chemical and biological processes. She hasrnbuilt valuable results after years of experience in these researches. Sriprasert completed BEngrnin Environmental Engineering from King Mongkut’s University of Technology Thonburi,rnThailand. She has also completed her MEng in the same field at Chulalongkorn University,rnThailand. Currently, she is doing PhD at the University of Southampton, UK, she works onrnapplication of two- and three- phase flow for anaerobic membrane cleaning.
Heavy metals pollutants from various types of industrial effluents such as metal plating,rntanneries, batteries, mining and electronic parts facilities, etc., become seriouslyrnenvironmental problems nowadays. Chemical precipitation, particularly, using hydroxidernprecipitation technique is the most widely implementation for soluble heavy metals removalrnfrom industrial wastewater due to its relatively inexpensive and simple application. Sulfidernprecipitation is also concerned one of the most effective method to treat heavy metal ionsrnregarding to its non-amphoteric sludge characteristics. In addition, metal sulfide sludge hasrnshown better thickening and dewatering properties in comparison with metal hydroxidernsludge.rnIn this study, real complex rising wastewater from printed circuit board manufacturingrnindustry with initial pH of 8.1, 350 mg/L suspended solids (SS), 221 NTU turbidity, heavyrnmetals in term of total and dissolved Cu and Ni of 86.6, 41.3 and 12.4, 4.3 mg/L,rnrespectively, have been tested with 0 – 5 folds Na2S of stoichiometry (considering to Curnremoval) to evaluate Cu and Ni removal efficiencies. Thereafter, sulfide precipitatedrnwastewater was further treated by cationic and anionic polyelectrolytes under dosing rates ofrn0.25 – 5.0 mg/L in order to evaluate sludge settling ability.rnThe results showed that optimum dosage of Na2S was 1.5 times of stoichiometry for copperrnremoval with 5 minutes of reaction time. In this stage, it found that Cu and Ni concentrationsrnand turbidity have been reduced for 98.1 and 98.6 and 99.9 %, respectively. Optimumrndosages of cationic and anionic polyelectrolytes were found to be the same value at 4 mg/L,rncorresponding to total Cu removal of 99.1 and 99.2 %, Ni removal of 91.1 and 89.5 % forrncationic and anionic polyelectrolytes application, respectively. Removing SS values inrnsupernatant after cationic and anionic polyelectrolytes adding were 28 and 16 mg/L, referringrnto SV30 of 60 and 65 mL/L, which sludge setting velocities have been improved to 11 andrn13-folds, respectively. Precipitated sludge characteristics obtained from XRD presentedrnamorphous form with recovered Cu and Ni in dried sludge of 11.6 – 12.3 % and 0.006 –rn0.007 % (w/w) for cationic and anionic polyelectrolytes applying, respectively.
Mamdouh I Nassar has completed his Bachelor’s degree from Biology Department, Faculty of\r\nScience, Cairo University; MSc degree at the same University and PhD degree in Channel System at University of Maryland College Park (USA) and Cairo University. He did many\r\nstudies in the field of sleeping sickness and Malaria diseases of vectors Stomoxys calcitrans and\r\nAnopheles in USDA Florida, Jazan and Jeda. He is the Staff Member at University of Maryland\r\nCollege Park, USA. He is a Professor of Biological Sciences at Cairo University, King Abd-\r\nAlziz, Univ. Jazan, and King Khalid Universities. He has worked as laboratory staff, for dietary Microbiology at Environmental system service, Beltsville, USA. He also was a Consultant Advisor at Home Care Company and Al-Nasr Chemicals Company.
Recent growth in nanomaterials application in different science fields needs to understand the advancement of the base for engineering and create unique properties targeted towards specific applications. Historically, various fields such as biology, medicine, environmental science, and agriculture have employed the successful and safe use of nanomaterials. However, use in agriculture, especially for pest control and plant protection with nanoparticle materials is an under-explored area in the research community. Preliminary studies show that the potential of nanomaterials in improving pest control, plant protection, pathogen detection, chemical hazardous and residual effects of pesticides. This review summarizes nanomaterials application in good future agricultural assessment; helps to develop safety methods for pesticides through very careful egulation with minimal impact on human health and the environment. Wellmaintained equipment with precautions that are required of pesticide application that could minimize human health exposure to pesticides and their adverse effects on the environment are also discussed.