The present work aimed to study the efficiency of nanofiltration (NF) and reverseosmosis (RO) process for water recovery from electroplating wastewater and study the factors affecting the performance of two membrane processes. Nanofiltration and reverse osmosismembranes are made from polyamide as spiral wound module. The inorganic materials ZnCl 2 CuCl2 .2H2O, NiCl.2.6H2O and CrCl3.6H2O were used as feed solutions. The operating parametersstudied were: operating time, feed concentrations for heavy metal ions, operating pressure, feed flow rate, feed temperature and feed pH. The experimental results showed, the permeateconcentration increased and water flux decreased with increase in time from 0 to 70 min. Thepermeate concentrations increased and flux decreased with increase in feed concentrations from 10 to 300 mg/l. Raising of pressure from 1 to 4 bar, permeate concentration decreased for ROfor NF decreased and then increased at high pressure and increase the flux. The rises of flow ratefrom 20 to 50 l/h decreased permeate concentration and the flux increase. The rises oftemperature from 26 to 40 °C, increased permeate concentration and increased the flux. The risein pH from 4 to 7, decreased the flux as the pH goes from acidic side towards alkaline. Thepolyamide nanofiltration membrane had allowed permeation of chromium and copper ions tolower than permissible limits. Nanofiltration membrane had allowed permeation of nickel andzinc ions at low concentration of these ions. The polyamide RO membrane gave a highefficiency for removal of chromium, copper, nickel and zinc and it had allowed permeation ofthese ions to the lower than permissible limits. The rejection at first three minutes when the feed concentration approximately was constant for chromium in NF and RO, was 99.7% and 99.93%for copper was 98.43% and 99.33%, for zinc was 97.96% and 99.49%, and for nickel was97.18% and 99.49% respectively. The maximum recovery for chromium in NF and RO was
71.75% and 48.5%, for copper was 75.62% and 50.68%, for zinc was 80.87% and 54.56%, fornickel was 60.06% and 46.18% respectively. For a mixture of synthetic electroplating wastewater, nanofiltration and reverse osmosis membranes have a high rejection percentage for heavy metal ions. It was obtained pure water and concentrations of less than allowable limits forheavy metals in the case of the mixture.
The ability of insurance companies to achieve goals depends on their ability to meet customers' requirements, and this requires them to identify target markets and respond to needs and wishes of the markets, the skill is to convince the company to operate what is in the interest of the customer if he is convinced the customer service provided to him, he would repeat to deal with, and where the cost of maintaining existing customers is less than the cost of attracting new customers, the insurance companies that is working hard to maintain their customers, the more customer satisfaction with the services provided has increased loyalty and weakened the ability of competitors lured.
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... Show MorePregnancy pose an additional burden on the body of the mother so as to meet their needs and the needs of the fetus and the body's need to iron increases excessively during pregnancy and iron is an essential element for the formation of hemoglobin blood Either hemoglobin is the key ingredient for red blood cells which carries oxygen to parts of the body, alas, most of the pregnant women begin their pregnancy inadequate stocks of iron in their bodies, which does not cover their need and requirement of the fetus, especially in the second and third trimesters of pregnancy When you reach the mother to the period in which they did not have the adequate amount of iron to produce hemoglobin become the mother was anemic So emerged the problem of
... Show MoreWith their strategic and geographical positions, Japan and Iraq are one of the major
countries in the world, especially to the United States. Japan lies near the two American
Continents, separated only by the Pacific and it is only normal to have the interests of both
countries crossed and joined in the Far East region. This made the occupation of Japan an
inventible matter in the second half of the 20th century. Iraq, on the other hand, has strategic
position in the Middle East, being surrounded by many active countries like Turkey, Iran, and
Gulf countries, besides Iraq’s oil wealth which is needed by such industrial country like the
United States.
In the present study, activated carbon supported metal oxides was prepared for thiophene removal from model fuel (Thiophene in n-hexane) using adsorptive desulfurization technique. Commercial activated carbon was loaded individually with copper oxide in the form of Cu2O/AC. A comparison of the kinetic and isotherm models of the sorption of thiophene from model fuel was made at different operating conditions including adsorbent dose, initial thiophene concentration and contact time. Various adsorption rate constants and isotherm parameters were calculated. Results indicated that the desulfurization was enhanced when copper was loaded onto activated carbon surface. The highest desulfurization percent for Cu2O/AC and o
... Show MoreBackground: Alveolar ridge expansion is proposed when the alveolar crest thickness is ≤5 mm. The screw expansion technique has been utilized for many years to expand narrow alveolar ridges. Recently, the osseodensification technique has been suggested as a reliable technique to expand narrow alveolar ridges with effective width gain and as little surgical operating time as possible. The current study aimed to compare osseodensification and screw expansion in terms of clinical width gain and operating time. Materials and methods: Forty implant osteotomies were performed in deficient horizontal alveolar ridges (3–5 mm). A total of 19 patients aged 21–59 years were randomized into two groups: the screw expansion group, which invo
... Show MoreA modified chemical method was used to prepare titanium dioxide nanoparticles (TiO2 NPs), which were diagnosed by several techniques: X-ray diffraction, Fourier transform infrared, field emission scaning electron microscopy, energy disperse X-ray, and UV-visible spectroscopy, which proved the success of the preparation process at the nanoscale level. Where the titanium oxide particles have an average particle size equal to 6.8 nm, titanium dioxide particles were used in the process of adsorption of Congo red dye from its aqueous solutions using a batch system. The titanium oxide particles gave an adsorption efficiency of Congo red dye up to more than 79 %. The experimental data of the adsorption process were analyzed with kinetic models and
... Show MoreObjective: The aim of this study was to compare the marginal microleakage between bulk-fill, preheated bulk-fill, and bulk-fill flowable composite resins above and below cemento-enamel junction (CEJ) using micro-computed tomography. Methods: Sixty freshly extracted premolar teeth were prepared with a slot shaped cavities of a total of 120 Class II: 3mm (bucco-lingual), 2mm (mesio-distal) with mesial-gingival margin located 1mm coronal to CEJ, and distal gingival margin located 1mm apical to the CEJ. The samples were randomly divided into two main groups according to the restorative material (Tetric EvoCeram and 3M Filtek), and each group was further sub-divided into three subgroups according to the consistency (bulk fill, preheated bulk fil
... Show MoreWheat straw was modified with malonic acid in order to get low cost adsorbent have a good ability to remove copper and ferric ions from aqueous solutions, chemical modification temperature was 120°C and the time was 12 h. Parameters that affect the adsorption experiments were studied and found the optimum pH were 6 and 5 for copper and iron respectively and the time interval was 120 min and the adsorbent mass was 0.1 g. The values for adsorption isotherms parameters were determined according to Langmuir [qmax were 54.64 and 61.7 mg/g while b values were 0.234 and 0.22 mg/l] , Freundlich [Kf were 16.07 and 18.89 mg/g and n were 2.77 and 3.16], Temkin [B were 0.063 and 0.074 j/mol and At were 0.143 and 1.658 l/g] and for Dubinin-Radushkev
... Show MoreSeveral recent approaches focused on the developing of traditional systems to measure the costs to meet the new environmental requirements, including Attributes Based Costing (ABCII). It is method of accounting is based on measuring the costs according to the Attributes that the product is designed on this basis and according to achievement levels of all the Attribute of the product attributes. This research provides the knowledge foundations of this approach and its role in the market-oriented compared to the Activity based costing as shown in steps to be followed to apply for this Approach. The research problem in the attempt to reach the most accurate Approach in the measurement of the cost of products from th
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