Mechanism of combination membrane and electro-winning process on treatment and remediation of Cu2+ polluted water body.
Mechanism of treatment and remediation of synthetic Cu2+ polluted water body by membrane and electro-winning combination process was investigated. The influences of electrolysis voltage, pH, and electrolysis time on the metal recovery efficiencies were studied. Relationship between trans-membrane pressure drop (DeltaP), additions ratio, initial Cu2+ concentration on operating efficiency, stability of membrane and the possibility of water reuse were also investigated. The morphology of membrane and electrodes were observed using scanning electron microscopy (SEM), the composition of surface deposits was ascertained using combined energy dispersive X-ray spectroscopy (EDX) and atomic absorption spectrophotometer. The results showed that using low pressure reverse osmosis (LPRO), Cu2+ concentration could increase from 20 to 100 mg/L or even higher in concentrated solutions and permeate water conductivity could be less than 20 microS/cm. The addition of sodium dodecy/sulfate sodium dodecyl sulfate improved Cu2+ removal efficiency, while EDTA had little side influence. In electro-reduction process, using plante electrode cell, Cu2+ concentration could be further reduced to 5 mg/L, and the average current efficiency ranged from 9% to 40%. Using 3D electrolysis treatment, Cu2+ concentration could be reduced to 0.5 mg/L with a current efficiency range 60%-70%.
Removal of pollutant from industrial effluent using ion – exchange resin
Heavy metals are found as pollutant in industrial waste waters. Mainly it is originating from chemical anufacturing, painting and coating, extractive metallurgy, mining,nuclear, and other industries. Heavy metals exert a deleterious effect on the fauna and flora of lakes and streams. One of the potential remedies to this problem is the use of adsorption technologies. A resin named Tulsion A-23 is used for the removal of copper ion from water in this experiment. Aim of the experiment is to study the influences of various factors, such as contact time, pH of solution, initial adsorbate concentration, initial metal ion concentration and temperature, on the sorption and optimize their values. Experimental results show that resin had a good adsorption capacity for copper and could reduce the concentrations of copper in the wastewater. Suitable time for the operation is found to be 110 min. at solution pH of 6 with 400mg/L of resin and initial concentration of copper 60mg/L.Removal of copper at these optimized parameter is found to be 99.25 %. After that the removal of copper becomes practically very slow.The experimental data is well fitted with Temkin adsorption isotherm and follows second order rate kinetics.Based on these results we can conclude that it is possible to use this resin for removing copper from waste water.
Beyond East–West: Marginality and National Dignity in Finnish Identity Construction
Since the end of the Cold War it has become common for Finnish academics and politicians alike to frame debates about Finnish national identity in terms of locating Finland somewhere along a continuum between East and West. Indeed, for politicians, properly locating oneself (and therefore Finland) along this continuum has often been seen as central to the winning and losing of elections. For example, the 1994 referendum on EU membership was largely interpreted precisely as an opportunity to relocate Finland further to the West. Indeed, the tendency to depict Finnish history in terms of a series of “Westernizing” moves has been notable, but has also betrayed some of the politicized elements of this view. However, this framing of Finnish national identity discourse is not only sometimes politicized but arguably is also too simplified and results in blindness towards other identity narratives that have also been important through Finnish history, and that are also evident (but rarely recognized) today as well. In this article we aim to highlight one of these that we argue has played a key role in locating Finland in the world and in formulating notions of what Finland is about, what historical role and mission it has been understood as destined to play, and what futures for the nation have been conceptualized as possible and as providing a source of subjectivity and national dignity.