Sharif Digital Repository

The removal of glyphosate, one of the most widely used herbicide, with membrane bioreactor (MBR) was studied. Beside of glyphosate, the synthetic wastewater contained molasses and other salts as nutrient source. The membrane was made from polypropylene and was immersed in the bioreactor. The COD of the feed was adjusted by varying the ratio of glyphosate to molasses. The total COD was 500, 750 and 1000 mg/L. The resulted showed that when the bioreactor coupled with membrane the removal efficiency increased. The increase was attributed to higher concentration of biomass or MLSS in the MBR. The average of MLSS in the MBR was 8500 mg/L while in bioreactor without cell recycling and in batch... 

In the present work, the combination of single drop liquid phase microextraction and gas chromatography-mass detector (GC-MS) was used for determination of pesticides, Clodinafop, Haloxyfop and Fenoxyprop in natural water samples. a novel techniques based on SDME for develop in which solvents with higher density than water was successfully used. this technique could overcome some limitations of conventional SDME such as instability of organic droplet and limited stirrer rate in which result increasing the mass transfer rate and extraction efficiency. Experimental liquid phase microextraction (LPME) conditions, such as extracting solvent, stirring rate, micro drop volume, extraction time, pH... 

In this study, a new resorcinol-formaldehyde xerogel was synthesized based on sol-gel technology and employed as a sorbent for micro solid phase extraction (µ-SPE) of BTEX and some selected pesticides from aqueous samples.
In the first part, a µ-SPE method in combined with headspace solvent microextraction (HS-SME) along with gas chromatography- mass spectrometry detection (GC–MS) was developed for the analysis of BTEX in aqueous samples. In our knowledge, this is for the first time that these two different extraction methods has been coupled to maximize the advantage of each extraction method. Influential parameters such as the peristaltic pump flow rate, extraction volume, extraction... 

Atrazine is widely used in the agriculture as an herbicide. Due to its high mobility, Atrazine leaks into the groundwater, surface waters, and drinking water wells. Many physical and chemical methods have been suggested for removing Atrazine from aquatic environments. However, these methods are very costly, have many performance problems, produce a lot of toxic intermediates which are very harmful and dangerous, and cannot completely mineralize Atrazine. In this study, biodegradation of Atrazine by microbial consortium was evaluated in the aquatic environment. In order to assess the Atrazine removal from the aquatic environment, Fixed-Bed biofilm reactor and Moving Bed Biofilm Reactor were...