The synthesis and structural characterization of new dithiocarbamate (DTC) ligand and some of its dinuclear transition metal complexes are described. The free dithiocarbamate ligand was prepared through several synthetic routes, including Schiff-base formation. The reaction of 2-aminopropane with terephthaldehyde leads to the formation of Schiff_base which is reduced by methanolic NaBH4 to the corresponding secondary diamine. Diamine( N,N'_ (1,4 phenylenebis (methylene)) bis(propan-2 amine)) reacts with (CS2) in a basic solution of (KOH) to provide the corresponding bis(dithiocarbamate) free_ligand, which undergoes complexation with the appropriate metal (II) chloride to constitute macrocyclic complexes. Characterization of the ligand and its complexes was achieved by FTIR, UV-Vis, melting points, conductance, magnetic susceptibility, and 1H, 13C NMR spectroscopy. The analytical and spectroscopic data were employed to obtain the suggested geometries around metal centres. These studies revealed the formation of dinuclear macrocyclic complexes of the general formula [M(L)]2 (where M= Mn(II) , Fe(II), Co(II), Ni(II), Cu(II) and Zn(II)), with tetrahedral. geometries for Mn(II) , Fe(II), Co(II) and Zn(II), and square. planar geometry with Ni(II) and Cu(II) complexes.
In this work, a novel biocatalytic process for the production of 7-methylxanthines from theobromine, an economic feedstock has been developed. Bench scale production of 7-methlxanthine has been demonstrated. The biocatalytic process used in this work operates at 30 OC and atmospheric pressure, and is environmentally friendly. The biocatalyst was E. coli BL21(DE3) engineered with ndmB/D genes combinations. These modifications enabled specific N7- demethylation of theobromine to 7-methylxanthine. This production process consists of uniform fermentation conditions with a specific metabolically engineered strain, uniform induction of specific enzymes for 7-methylxanthine production, uniform recovery an
... Show MorePharmaceuticals are widely distributed in different applications and also released into the environment. Adsorption of Ciprofloxacin HCl (CIPH) on Porcelinaite was studied at ambient conditions. The adsorption isotherms can be well described using the Freundlich and Temkin equations. The pH of the solution influences significantly the adsorption capacity of Porcelinaite, the adsorption of CIPH increased from the initial pH 1.3 and then decreased over the pH rang of 3.8-9. The adsorption is sensitive to the change in ionic Strength, which indicate that electrostatic attraction is a significant mechanism for sorption process. The enthalpy change (ΔH) for the adsorption of CIPH onto Porcelinaite signifies an endothermic adsorption. The ΔG va
... Show MoreThis research aimed to examine the effect of concentration of dyes stuff, contact time, temperature and ratio of adsorbent weight in (gm) to volume of solution in (ml) on the percentage removal. Two dyes were used; direct blue 6 and direct yellow and the adsorbent was the maize cob. Batch experiments were performed by contacting different weights of adsorbent with 50 ml of solution of desired concentration with continuous stirring at various temperatures. The percentage of removal was calculated and the maximum percentage of removal was 80%. And as the concentration of solution, contact time, temperature and the ratio of adsorbent to volume of solution increase the percentage of removal increase.
The adsorption behavior of methyl orange from aqueous solution on Iraqi bentonite was investigated. The effects of various parameters such as initial concentration of methyl orange, amount of adsorbent, ionic strength and temperature on the adsorption capacity has been studied. The percentage removal of methyl orange increased with the decrease of initial concentration of methyl orange and it increased with the increase of dose of adsorbent. The adsorbed amount of methyl orange decrease with increasing ionic strength and an increase in temperature. The equilibrium adsorption isotherms have been analysed by the linear, Langmuir and Temkin models. The Langmuir isotherms have the highest correlation coefficients. Thermodynamic paramet
... Show MoreThe Wheat husk is one of the common wastes abundantly available in the Middle East countries especially in Iraq. The present study aimed to evaluate the Wheat husk as low cost material, eco-friendly adsorbents for the removal of the carcinogenic dye (Congo red dye) from wastewater by investigate the effect of, at different conditions such as, pH(3-10), amount of adsorbents (1-2.3gm/L),and particle size (125-1000) μm, initial Congo red dye concentration(10, 25 , 50 and 75mg/l) by batch experiments. The results showed that the removal percentage of dye increased with increasing adsorbent dosage, and decreasing particle size. The maximum removal and uptake reached (91%) , 21.5mg/g, respectively for 25 initial concent
... Show MoreThe current study aims to produce cellulase enzyme from Streptomyces spp. isolates and study the effect of some cultural conditions on cellulase production; biofuel production from cellulotic waste through enzymatic and acids hydrolysis. Out of 74 isolates of Streptomyces sp. were screened for cellulse production in solid and liquid media. Results showed higher capability of isolate Streptomyces sp. B 167 for cellulase production and bioconversion of cellulose, therefore selected for further studies. The results of optimization revealed that the cellulase enzyme productivity by the selected isolate reached 2.1 and 2.28 U/ml after 48 h of incubation time and pH 7 respectively. Cellulase productions in tested isolate improved (2.57 U/ml) b
... Show MoreThe removal of Anit-Inflammatory drugs, namely; Acetaminophen (ACTP), from wastewater by bulk liquid membrane (BLM) process using Aliquat 336 (QCl) as a carrier was investigated. The effects of several parameters on the extraction efficiency were studied in this research, such as the initial feed phase concentration (10-50) ppm of ACTP, stripping phase (NaCl) concentration (0.3,0.5,0.7 M), temperature (30-50oC), the volume ratio of feed phase to membrane phase (200-400ml/80ml), agitation speed of the feed phase (75-125 rpm), membrane stirring speed (0, 100, 150 rpm), carrier concentration (1, 5, 9 wt%), the pH of feed (2, 4, 6, 8, 10), and solvent type (CCl4 and n-Heptane). The study shows that high ext
... Show MorePharmaceuticals are widely distributed in different applications and also released into the environment. Adsorption of Ciprofloxacin HCl (CIPH) on Porcelinaite was studied at ambient conditions. The adsorption isotherms can be well described using the Freundlich and Temkin equations. The pH of the solution influences significantly the adsorption capacity of Porcelinaite, the adsorption of CIPH increased from the initial pH 1.3 and then decreased over the pH rang of 3.8-9. The adsorption is sensitive to the change in ionic Strength, which indicate that electrostatic attraction is a significant mechanism for sorption process. The enthalpy change (∆H) for the adsorption of CIPH onto Porcelinaite signifies an endothermic adsorption. The ∆G
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