review of the performance of carbon nanotubes in reducing environmental pollution

Introduction: In recent times, one of the most important purposes of sustainable development has been defined as the protection of environmental health. Using appropriate and innovative infrastructures such as nanotechnology is a solution to walk along the path of sustainable development and solves many environmental problems. The purpose of this study is to review the application of carbon nanotubes in the removal of environmental pollutants, based on conducted studies

Materials and Methods: All scientific data related to the issue were collected from scientific databases of Google Scholar, Scopus, Elsevier, and SID to evaluate and conduct the study. Keywords such as carbon nanotubes, environmental pollutant, sustainable development, and environmental health were used. 85 articles were also used in this review research [1993-2016]

Results: Based on the evaluated studies, the results indicated that common methods of sewage treatment are not enough to remove the mentioned environmental pollutants completely. In the mentioned methods, despite high decomposition, the amount of mineralization has been reduced and the toxicity of wastewaters has remained unchanged or has increased. Adsorption has been propounded due to its simplicity and lower energy consumption compared with other methods. Carbon nanotubes [CNTs] are unique one-dimensional macromolecules which have high thermal resistance and chemical stability. Adsorption through CNT as the adsorbent in the treatment of drinking water and sewage polluted with pharmaceutical, petroleum, heavy metal, and leachate pollutants has been studied widely

Conclusion: This study indicated CNT as effective adsorbents that have high potential to protect the environment and promote sustainable development

Removal methods of antibiotic compounds from aqueous environments-a review

Introduction: Antibiotics as a type of pharmaceutical compounds are widely used in modern medicine and veterinary industries. They enter the environment in different ways, including agricultural runoff, direct discharge of urban wastewater treatment or human waste, direct disposal of medical, veterinary industrial waste and etc. Antibiotics have been able to influence the microbial population. Their continuous presence in the environment can lead to bacterial resistance and in recent years the issue has caused serious concerns in the scientific community

Methods: Unfortunately, In spite of the extensive investigations, there is still a considerable lack of integrated and classified information to assess the environmental risks of antibiotics. Therefore, in the current study, the removal of these compounds from aqueous solutions was studied. This study was carried out on the basis of surveys accomplished in recent decades and also the ones published in databases such as Google Scholar, PubMed, Elsevier, Scopus, Springer, Magiran and SID using Anti-bacterial agents, Antibiotic, Wastewater, removal methods as the keywords

Results: Advanced treatment processes such as ozonation, advanced oxidation, activated carbon, Nano filtration and reverse osmosis can remove higher levels of antibiotics

Conclusion:Generally, the biological and chemical processes alone are not effective for antibiotics, removal from aquatic environments, while combination of advanced oxidation and biological treatment processes can effectively reduce the amount of antibiotic

Biodegradation of linear alkyl benzene sulfonate by sequencing batch reactor in sanitary wastewater

Introduction: Detergents lead to many environmental problems. The main aim of this study was to evaluate sequencing batch reactor [SBR] efficiency on Linear alkyl benzene sulfonate [LAS] removal

Materials and Methods: In this experimental study, to investigate the removal efficiency of LAS, a SBR reactor was used. A roughly 12-hour operating cycle was chosen which included the discharge time [30 min], the filling time [60 min], and sedimentation [1 hr], while the remaining time was devoted to aerating. In this research 48 samples were taken and analyzed. Sampling and testing were performed according to the standard methods of water and wastewater examination

Results: The results showed that minimum and maximum removal efficiencies of LAS in SBR reactor were 92 % and 99.5 %, respectively. The average removal of COD was 92 %. It was observed that 1 mg/l used surfactants produced 2.3 +/- 0.3 mg COD

Conclusion: It can be concluded that SBR reactor is capable of removing LAS to meet desirable environmental standards