Air stripping for removal of Trichloroethylene (TCE), Chloroform (CF) and Dichloromethane (DCM) from water were studied in a bubble column (0.073 m inside dia. and 1.08 m height with several sampling ports). The contaminated water was prepared from deionized water and VOCs. The presence of VOCs in feed solution was single, binary or ternary components. They were diluted to the concentrations ranged between 50 mg/l to 250 mg/l. The experiments were carried out in batch experiments which regard the bubble column as stirred tank and only gas was bubbled through stationary liquid. In this case transient measurements of VOC concentration in the liquid phase and the measured concentration profiles were modeled by bubble aeration model (BAM) to fit the experimental data fairly well. The results from batch experiments show that the removal efficiency of VOCs increases with increasing gas flow rate or gas holdup. It is found a pH=10 give the best removal rate, but all experiments were adjusted at pH=8 which allow to study other operating conditions. TCE is being removed faster than the other two components for all systems and a single component was removed faster than binary or ternary system. The KLa values were evaluated by fitting the BAM to the experimental data. It is found that KLa increased with increasing gas flow rate and TCE exhibits the highest KLa values.
In this work two moles of 2-amino benzothiazole were allowed to react with one mole of pyromellitic dianhydride to produce N,N‾-Bis-(benzathiazol-2-yl) pyromellitamic diacid [I] which was submitted to esterification via the reaction with dimethyl sulphate in sodium carbonate in acetone as a solvent to synthesize N,N‾-bis-(benzothiazol-2-yl) pyromellitam diacetate [II] .This ester was used to produce novel compounds through two paths :- Path one:- Reaction of ester [II] with hydrazine in ethanol as a solvent to form the corresebonding N,N‾-bis (benzothiazole-2-yl) –pyromellitamic acid hydrazide [III] which react with acetyl acetone in ethanol or with phthalic anhydride in dioxa
... Show MoreIn this work 2- mercaptobenzothiazole ( 2-MBT ) and some of its derivatives(1, 14 ,27) were prepared by using home made Auto clave .The synthesis involve treatment of 2- MBT or some of its derivatives with chloro acetyl chloride to give 1- chloro acetyl -2- MBT or the corresponding derivatives (2,15,28) . the product was treated with phenyl hydrazine to give the phenyl hydrazide derivatives (3,16,29) . The new derivatives(4-13, 17-26,30-39) were synthesized by reaction of the phenyl hydrazide derivatives with different aromatic aldehydes in the presence of Acetic Acid . Structure of all the prepared compounds confirmation were proved using FTIR , elemental analysis (C .H .N .S ) in addition to melting points.
Some new mono isoimides of asymmetrical pyromillitdiimide derived from pyromellitic dianhydride were synthesized and studied by their melting points , FTIR , and 1HNMR spectroscopy and C.H.N analysis (for some of them) and it was proved that the mechanism of the formation of these isoimides followed , the mechanism suggested by Cotter et al . by using N, N─- dicyclohexylcarbodiimide as dehydrating agent , in spite of the groups attached to the phenyl moiety as mentioned in literatures .
New 1,2,4-triazole derivatives of 2-mercaptobenzimidazole (MB) are reported. Ethyl (benzimidazole-2-yl thio) acetate (1) has been prepared by condensing 2-mercaptobenzimidazole with ethylchloroacetate. The ester (1) on reacting with hydrazine hydrate gave the corresponding acetohydrazide(2)which was reacted separately with phenylisocyanate and phenylisothiocyanate, followed by ring closure in an alkaline medium giving 3-[(benzimidazole-2-yl thio) methyl]-4-phenyl-1,2,4-triazole-5-ol and 3-[(benzimidazole-2-yl thio) methyl]-4-phenyl-1,2,4-triazole-5-thiol respectively (6,7). Reaction of acetohydrazide (2) with CS2 and ethanol/KOH, gave dithiocarbazate salt (8). Cyclization of (8) with hydrazine hydrate gave 3-[(benzimi
... Show MoreSelective recovery of atropine from Datura innoxia seeds was studied. Applying pertraction in a rotating film contactor (RFC) the alkaloid was successfully recovered from native aqueous extracts obtained from the plant seeds. Decane as a liquid membrane and sulfuric acid as a stripping agent were used. Pertraction from native liquid extracts provided also a good atropine refinement, since the most of co-extracted from the plant species remained in the feed or membrane solution. Solid–liquid extraction of atropine from Datura innoxia seeds was coupled with RF-pertraction in order to purify simultaneously the extract obtained from the plant. Applying the integrated process, proposed in this study, a product containing 92.6% atropine was
... Show MoreIn the present work, 9-fluorenone-2-carboxylic acid methyl ester (1) was prepared from 9-fluorenone-2-carboxylic acid and then converted into the acid hydrazide (2). Compound (2), is the key intermediate for the synthesis of several series of new compounds such as substituted 1,3,4-oxadiazole derivatives (3-6) were synthesized from the condensation of different substituted benzoic acids with compound (2) using POCl3 as condensing agent. Treatment of compound (2) with formic acid gave the N-formyl hydrazide (7), which upon refluxing with phosphorous pentoxide in benzene yielded the corresponding 5-(9-fluorenone-2-yl)-1,3,4-oxadiazole (8). Reaction of hydrazide (2) with phenyl isocyanate to give N-phenyl semicarbazide derivative (9), then thi
... Show MoreA mixture of algae biomass (Chrysophyta, Cyanophyta, and Chlorophyte) has been investigated for its possible adsorption removal of cationic dyes (methylene blue, MB). Effect of pH (1-8), biosorbent dosage (0.2-2 g/100ml), agitated speed (100-300), particle size (1304-89μm), temperature (20-40˚C), initial dye concentration (20-300 mg/L), and sorption–desorption were investigated to assess the algal-dye sorption mechanism. Different pre-treatments, alkali, protonation, and CaCl2 have been experienced in order to enhance the adsorption capacity as well as the stability of the algal biomass. Equilibrium isotherm data were analyzed using Langmuir, Freundlich, and Temkin models. The maximum dye-sorption capacity was 26.65 mg/g at pH= 5, 25
... Show MoreThe presence of alkaloids in Crassula ovata is a topic that is still unexplored, as there are no published studies on the matter. This study demonstrates the presence of an alkaloid compound (and its class) for the first time in Crassula ovata. The plant material was defatted with n-hexane, and a Soxhlet apparatus was used for the extraction process, while the acid-base method was used for the isolation of alkaloids from the chloroform fractions. The quaternary alkaloid was precipitated from the aqueous layer spontaneously, in high quantity. By using standard spectroscopic methods (including liquid chromatography - mass spectroscopy) we were able to clarify the structure of the precipi¬tated compound as a tetrahydroprotoberberine a
... Show MoreThis study includes isolation, purification, and identification of algae from different aquatic environments in Baghdad city. Nine unialgal cultures were obtained. These algal cultures included 6 species of blue-green algae (Microcystis aeruginosa, Microcystis flos-aquae, Oscillatoria limnetica, Nostoc carneum, Westillopesis prolifica, Mastigocluds lamiosus), and 3 species of green algae (Mougeotia sclaris, Scenedesmus dimorphus and Chlorella vulgaris). In addition that aerial parts from Convolvulus arvensis were collected. Terpens, alkaloids and phenols were extracted of mentioned plant, and the antialgal activity of extracts types were evaluated in 3 concentrations (5, 10, and 20 mg/ml) by wells and diffused in the agar media. Results
... Show More