Application of polyamide thin-film composite layered on polysulfone-GO/TiO2 mixed matrix membranes for removal of nitrotoluene derivatives from petrochemical wastewaters

Release of harmful organic intermediates or byproducts during the manufacture of petrochemical compounds is a serious problem in petrochemical plants. In this work, polysulfone membranes blended with GO/TiO₂ nanocomposite were synthesized by phase inversion method and coated with a polyamide layer formed by interfacial polymerization to prepare a thin-film composite (TFC) sample. Analysis and characterization of the sample were carried out by XRD, FE-SEM, BET, FTIR/ATR, AFM, TGA, and zeta potential. Results indicated that incorporation of GO/TiO₂ into the membrane structure enhanced porosity, surface roughness, and macrovoid formation along the cross-section of the sublayer and permeability of the membrane. The TFC membranes were applied to remove mononitrotoluene (MNT) and dinitrotoluene (DNT) as the basic intermediates of toluene diisocyanate (TDI). The membranes demonstrated high efficiency (>?90%) for the removal of MNT and DNT according to the charge exclusion mechanism and Donnan effect. Application of the TFC membrane for treatment of wastewater in the TDI plant showed that the removal of pollutants is variable in the range of 45–65% and 53–69% for the membrane with the highest flux and highest rejection in different transmembrane pressure, respectively.

     

CYP1A1 and GSTs common gene variations and presbycusis risk: a genetic association analysis and a bioinformatics approach

Environmental Science and Pollution Research - Antioxidant enzymes such as glutathione S-transferases (GSTs) and cytochromes P450 (CYPs) are involved in the metabolism and detoxification of...     

Magnetic nanoparticles incorporation into different substrates for dyes and heavy metals removal—A Review

Environmental Science and Pollution Research - Substantial discharge of hazardous substances, especially dyes and heavy metal ions to the environment, has become a global concern due to...     

Risk assessment of heavy metal(loid)s via Spinacia oleracea ingestion after sewage water irrigation practices in Vehari District

Environmental Science and Pollution Research - The use of sewage water as an irrigation source can be beneficial in agricultural practices, however, it may result in human health risks due to the...     

Environmental concerns and switching toward electric vehicles: geographic and institutional perspectives

Environmental Science and Pollution Research - Smog pollution deteriorates environmental quality and has severe health risks. This affects the daily lives of people in China, particularly in urban...     

Making spatial development scenario for south of Bushehr province,Iran, based on strategic foresight

In recent years, the science of foresight has been entered into planning activities by urban and regional planners and this science has impacted on planning activities. This study discusses spatial development in the south of Bushehr province using the foresight approach. The general aim of this research is to compile scenarios for the development of the mentioned study area which comprises the southern part of Bushehr province including four counties of Dayyer, Jam, Kangan and Asaluyeh. The main reason for selecting this region is their direct impressibility by major changes in the country’s oil and gas industry. This research has extremely made use of the Delphi and cross-impact analysis methods to develop foresight scenarios. Using the Delphi method, 30 initial factors were identified in the economic, political-security, linkages, science and technology, manufacturing, natural, social, infrastructural and residential issues and then the cross-impact matrix was used to investigate the impact of factors on each other. In the next step, the ranking of direct and indirect factors was determined by Micmac software and on this basis, the final refining in the selection of drivers was done. In the final stage, axes of future scenarios were presented and then the future scenarios were drawn. Results of this research indicate that two main drivers namely Iran’s international relations and energy resources are the main axes of scenarios. These two drivers have more uncertainty and higher importance than other factors and the results in four scenarios showing the possibility of each situation’s occurrence.     

Linear and non-linear relationships mapping the Henry’s law parameters of organic pesticides

This work aims to predict the air to water partitioning for 96 organic pesticides by means of the Quantitative Structure–Property Relationships Theory. After performing structural feature selection with Genetics Algorithms and Replacement Method linear approaches, it is found that among the most important molecular features appears the Moriguchi octanol–water partition coefficient, and higher lipophilicities would lead to compounds having higher Henry’s law constants. We also compare the statistical performance achieved by four fully-connected Feed-Forward Multilayer Perceptrons Artificial Neural Networks. The statistical results found reveal that the best performing model uses the Levenberg–Marquardt with Bayesian regularization (BR) weighting function for achieving the most accurate predictions.     

Phytoremediation of arsenic in mining‐contaminated areas: The future of transgenic technology

A considerable number of contaminated mining sites in Europe and other parts of the world pose environmental hazards. Given the multifaceted benefits of phytoremediation, screening of plant communities grown in contaminated areas is being conducted to identify hyperaccumulating plant species. A few arsenic (As) hyperaccumulating plants are found in tropical countries; however, generally, they are not grown in contaminated mining sites of cold and temperate countries (Europe and other parts of the world). The transgenic plants identified to date are not believed to be suitable for commercial use of phytoremediation. A few tolerant plant species in mining sites that are found to have elevated As levels primarily concentrate As in their roots. The remediation potential of many of these tolerant plants is limited because of their slow growth and low biomass. Therefore, phytostabilization of contaminated mining sites using tolerant plant species with high biomass and a more extensive root system is the only solution to date in Europe and some other parts of the world. © 2010 Wiley Periodicals, Inc.     

Food security and ecological footprint of coastal zone of Bangladesh

This paper presents the present status of food security and ecological footprint, an indicator of environmental sustainability of the coastal zones of Bangladesh. To estimate the present status of the food security and ecological footprint of the coastal zone of Bangladesh, primary and secondary data were collected, and the present status of food security and environmental degradation (in terms of ecological footprint) were calculated. To estimate the household food security, primary data were also collected from all the households in a representative selected village. A quantitative method for computation of food security in grain equivalent based on economic returns (price) is developed, and a method of measuring sustainable development in terms of ecological footprint developed by Wackernagel is used to estimate the environmental sustainability (Wackernagel and Rees in Our ecological footprint: reducing human impact on the earth. New Society, Gabrioala, BC, 1996; Chambers et al. in Sharing nature’s interest-ecological footprint as an indicator of sustainability. Earthscan, London, 2000). Overall status of food security at upazila levels is good for all the upazilas except Shoronkhola, Shyamnager and Morrelgonj, and the best is the Kalapara upazila. But the status of food security at household levels is poor. Environmental status in the coastal zones is poor for all the upazilas except Kalapara and Galachipa. The worst is in the Mongla upazila. Environmental status has degraded mainly due to shrimp culture. This study suggests that control measures are needed for affected upazilas and any further expansion of the shrimp aquaculture to enhance the food security must take into account the environmental aspects of the locality under consideration.     

Concentration and characterization of airborne particles in Tehran’s subway system

Particulate matter is an important air pollutant, especially in closed environments like underground subway stations. In this study, a total of 13 elements were determined from PM₁₀ and PM_2.5 samples collected at two subway stations (Imam Khomeini and Sadeghiye) in Tehran’s subway system. Sampling was conducted in April to August 2011 to measure PM concentrations in platform and adjacent outdoor air of the stations. In the Imam Khomeini station, the average concentrations of PM₁₀ and PM_2.5 were 94.4?±?26.3 and 52.3?±?16.5 μg m^?3 in the platform and 81.8?±?22.2 and 35?±?17.6 μg m^?3 in the outdoor air, respectively. In the Sadeghiye station, mean concentrations of PM₁₀ and PM_2.5 were 87.6?±?23 and 41.3?±?20.4 μg m^?3 in the platform and 73.9?±?17.3 and 30?±?15 μg m^?3, in the outdoor air, respectively. The relative contribution of elemental components in each particle fraction were accounted for 43 % (PM₁₀) and 47.7 % (PM_2.5) in platform of Imam Khomeini station and 15.9 % (PM₁₀) and 18.5 % (PM_2.5) in the outdoor air of this station. Also, at the Sadeghiye station, each fraction accounted for 31.6 % (PM₁₀) and 39.8 % (PM_2.5) in platform and was 11.7 % (PM₁₀) and 14.3 % (PM_2.5) in the outdoor. At the Imam Khomeini station, Fe was the predominant element to represent 32.4 and 36 % of the total mass of PM₁₀ and PM_2.5 in the platform and 11.5 and 13.3 % in the outdoor, respectively. At the Sadeghiye station, this element represented 22.7 and 29.8 % of total mass of PM₁₀ and PM_2.5 in the platform and 8.7 and 10.5 % in the outdoor air, respectively. Other major crustal elements were 5.8 % (PM₁₀) and 5.3 % (PM_2.5) in the Imam Khomeini station platform and 2.3 and 2.4 % in the outdoor air, respectively. The proportion of other minor elements was significantly lower, actually less than 7 % in total samples, and V was the minor concentration in total mass of PM₁₀ and PM_2.5 in both platform stations.