scholarly journals Recovery of Spent Sulphuric Acid by Diffusion Dialysis Using a Spiral Wound Module

2021 ◽  
Vol 22 (21) ◽  
pp. 11819
Author(s):  
Arthur Merkel ◽  
Ladislav Čopák ◽  
Lukáš Dvořák ◽  
Daniil Golubenko ◽  
Libor Šeda
Keyword(s):  
Free Acid ◽  
Volumetric Flow Rate ◽  
Membrane Degradation ◽  
Acid Yield ◽  
Ion Rejection ◽  
Regeneration Unit ◽  
One Year ◽  
Diffusion Dialysis ◽  
Feed Temperature ◽  
Spiral Wound

In this study, we assess the effects of volumetric flow and feed temperature on the performance of a spiral-wound module for the recovery of free acid using diffusion dialysis. Performance was evaluated using a set of equations based on mass balance under steady-state conditions that describe the free acid yield, rejection factors of metal ions and stream purity, along with chemical analysis of the outlet streams. The results indicated that an increase in the volumetric flow rate of water increased free acid yield from 88% to 93%, but decreased Cu2+ and Fe2+ ion rejection from 95% to 90% and 91% to 86%, respectively. Increasing feed temperature up to 40 °C resulted in an increase in acid flux of 9%, and a reduction in Cu2+ and Fe2+ ion rejection by 2–3%. Following diffusion dialysis, the only evidence of membrane degradation was a slight drop in permselectivity and an increase in diffusion acid and salt permeability. Results obtained from the laboratory tests used in a basic economic study showed that the payback time of the membrane-based regeneration unit is approximately one year.

Diffusion dialysis of sulfuric acid in spiral wound membrane modules: Effect of module number and connection mode

2015 ◽  
Vol 148 ◽  
pp. 25-31 ◽  
Author(s):  
Fabao Luo ◽  
Xu Zhang ◽  
Jiefeng Pan ◽  
Abhishek N. Mondal ◽  
Hongyan Feng ◽  
...  
Keyword(s):  
Sulfuric Acid ◽  
Membrane Modules ◽  
Diffusion Dialysis ◽  
Spiral Wound

PERFORMANCE OF DIFFUSION DIALYSIS FOR PICKLING EFFLUENT OPERATING UNDER A HIGH FLOW RATE

2016 ◽  
Vol 78 (5-3) ◽  
Author(s):  
Chantapala S. ◽  
Somattanai W. ◽  
Sudtida P. Thanasupsin
Keyword(s):  
Flow Rate ◽  
Metal Ion ◽  
Ionic Concentration ◽  
Feed Ratio ◽  
Driving Mechanism ◽  
Feed Flow Rate ◽  
Treatment Unit ◽  
Ion Rejection ◽  
Diffusion Dialysis ◽  
Waste Acid

Diffusion dialysis (DD) is a membrane separation process. The major driving mechanism is an ionic concentration gradient. An anion-exchange membrane (AEM) equipped with DD is efficiently used for purifying waste acid and metal ion separation. The goal of this laboratory-scale study is to investigate the efficiency of a diffusion dialyser (model HKY-001), which was equipped with an AEM (model DF120), to purify waste acid solution (sulphuric acid). This study was conducted with actual waste acid from a pickling bath of an electroplating manufacturer in Samut Prakarn Province. In the experimental tests, the operating parameters, such as time to reach equilibrium, feed flowrate, water to feed (Qwater/Qfeed) and type of stripping water, were varied. To examine the performance of this treatment unit, the concentration of H+ (mol.L-1), acid recovery (% as H+) and metal ion rejection (%) were monitored regularly. In conclusion, increasing the feed flow rate will likely decrease the H+ recovery (%). The rejection (%) of Zn, Mn and Pb is likely to increase with increases in the feed flow rate. A higher metal ion rejection (%) can be achieved at a lower water-to-feed ratio.  

Effect of feed temperature on permeate flux and mass transfer coefficient in spiral-wound reverse osmosis systems

Desalination ◽  
2002 ◽  
Vol 144 (1-3) ◽  
pp. 367-372 ◽  
Author(s):  
Mattheus F.A. Goosen ◽  
Shyam S. Sablani ◽  
Salha S. Al-Maskari ◽  
Rashid H. Al-Belushi ◽  
Mark Wilf
Keyword(s):  
Mass Transfer ◽  
Transfer Coefficient ◽  
Mass Transfer Coefficient ◽  
Reverse Osmosis ◽  
Permeate Flux ◽  
Feed Temperature ◽  
Spiral Wound

Between ‘Savage Man’ and ‘Most Faithful Englishman’ Manteo and the Early Anglo-Indian Exchange, 1584–1590

Itinerario ◽  
2000 ◽  
Vol 24 (2) ◽  
pp. 146-169 ◽  
Author(s):  
Michael Leroy Oberg
Keyword(s):  
North Carolina ◽  
Chesapeake Bay ◽  
One Year ◽  
Anglo Indian

In August of 1587 Manteo, an Indian from Croatoan Island, joined a group of English settlers in an attack on the native village of Dasemunkepeuc, located on the coast of present-day North Carolina. These colonists, amongst whom Manteo lived, had landed on Roanoke Island less than a month before, dumped there by a pilot more interested in hunting Spanish prize ships than in carrying colonists to their intended place of settlement along the Chesapeake Bay. The colonists had hoped to re-establish peaceful relations with area natives, and for that reason they relied upon Manteo to act as an interpreter, broker, and intercultural diplomat. The legacy of Anglo-Indian bitterness remaining from Ralph Lane's military settlement, however, which had hastily abandoned the island one year before, was too great for Manteo to overcome. The settlers found themselves that summer in the midst of hostile Indians.

Some Biological Applications of High Voltage Electron Microscopy

1974 ◽  
Vol 32 ◽  
pp. 298-299
Author(s):  
Hans Ris
Keyword(s):  
High Voltage ◽  
Chromosome Structure ◽  
Nerve Fibers ◽  
Good Resolution ◽  
High Voltage Electron Microscopy ◽  
Voltage Electron ◽  
University Of Wisconsin ◽  
High Voltage Electron ◽  
One Year ◽  
The University

The High Voltage Electron Microscope Laboratory at the University of Wisconsin has been in operation a little over one year. I would like to give a progress report about our experience with this new technique. The achievement of good resolution with thick specimens has been mainly exploited so far. A cold stage which will allow us to look at frozen specimens and a hydration stage are now being installed in our microscope. This will soon make it possible to study undehydrated specimens, a particularly exciting application of the high voltage microscope.Some of the problems studied at the Madison facility are: Structure of kinetoplast and flagella in trypanosomes (J. Paulin, U. of Georgia); growth cones of nerve fibers (R. Hannah, U. of Georgia Medical School); spiny dendrites in cerebellum of mouse (Scott and Guillery, Anatomy, U. of Wis.); spindle of baker's yeast (Joan Peterson, Madison) spindle of Haemanthus (A. Bajer, U. of Oregon, Eugene) chromosome structure (Hans Ris, U. of Wisconsin, Madison). Dr. Paulin and Dr. Hanna are reporting their work separately at this meeting and I shall therefore not discuss it here.

Osseointegration interface of calcified bone and endosseous implants

1992 ◽  
Vol 50 (2) ◽  
pp. 1096-1097
Author(s):  
K.E. Krizan ◽  
J.E. Laffoon ◽  
M.J. Buckley
Keyword(s):  
Structure And Function ◽  
Titanium Implants ◽  
En Bloc ◽  
Endosseous Implants ◽  
Ultrastructural Studies ◽  
The Past ◽  
Cacodylate Buffer ◽  
One Year ◽  
And Function

With increase use of tissue-integrated prostheses in recent years it is a goal to understand what is happening at the interface between haversion bone and bulk metal. This study uses electron microscopy (EM) techniques to establish parameters for osseointegration (structure and function between bone and nonload-carrying implants) in an animal model. In the past the interface has been evaluated extensively with light microscopy methods. Today researchers are using the EM for ultrastructural studies of the bone tissue and implant responses to an in vivo environment. Under general anesthesia nine adult mongrel dogs received three Brånemark (Nobelpharma) 3.75 × 7 mm titanium implants surgical placed in their left zygomatic arch. After a one year healing period the animals were injected with a routine bone marker (oxytetracycline), euthanized and perfused via aortic cannulation with 3% glutaraldehyde in 0.1M cacodylate buffer pH 7.2. Implants were retrieved en bloc, harvest radiographs made (Fig. 1), and routinely embedded in plastic. Tissue and implants were cut into 300 micron thick wafers, longitudinally to the implant with an Isomet saw and diamond wafering blade [Beuhler] until the center of the implant was reached.

Calcium ion imaging in plant cells

1993 ◽  
Vol 51 ◽  
pp. 132-133
Author(s):  
Peter K. Hepler ◽  
Dale A. Callaham
Keyword(s):  
Plant Cell Wall ◽  
Cytoplasmic Membrane ◽  
Fluorescent Dyes ◽  
Free Acid ◽  
Methyl Esters ◽  
Free Calcium ◽  
Local Concentration ◽  
Ion Imaging ◽  
Membrane Compartments ◽  
Free Acid Form

Calcium ions (Ca) participate in many signal transduction processes, and for that reason it is important to determine where these ions are located within the living cell, and when and to what extent they change their local concentration. Of the different Ca-specific indicators, the fluorescent dyes, developed by Grynkiewicz et al. (1), have proved most efficacious, however, their use on plants has met with several problems (2). First, the dyes as acetoxy-methyl esters are often cleaved by extracellular esterases in the plant cell wall, and thus they do not enter the cell. Second, if the dye crosses the plasma membrane it may continue into non-cytoplasmic membrane compartments. Third, even if cleaved by esterases in the cytoplasm, or introduced as the free acid into the cytoplasmic compartment, the dyes often become quickly sequestered into vacuoles and organelles, or extruded from the cell. Finally, the free acid form of the dye readily complexes with proteins reducing its ability to detect free calcium. All these problems lead to an erroneous measurement of calcium (2).

Effectiveness of a 24-hour nicotine patch in conjunction with a cognitive behavioural programme: one year outcome transdermal

Addiction ◽  
1997 ◽  
Vol 92 (1) ◽  
pp. 27-31
Author(s):  
Robyn L. Richmond ◽  
Linda Kehoe ◽  
Abilio Cesar De Almeida Neto
Keyword(s):  
Nicotine Patch ◽  
Cognitive Behavioural ◽  
One Year
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