Publications
Comparative Performance of NF90 and NF270 Nanofiltration Membranes in Direct Dye Removal from Aqueous Solutions
Aug 31, 2025Journal International Journal of Heat and Technology
Publisher International Information and Engineering Technology Association
DOI https://doi.org/10.18280/ijht.430422
This work uses NF90 and NF270 nanofiltration membrane separation to remove direct dyes from aqueous solutions. DR80 and DY8 are the direct dyes used in this investigation. The textile industry releases direct dye effluent into rivers and oceans, causing several major problems. The purpose of this study is to compare the dye rejection and permeate flow performance of nanofiltration membranes (NF90 and NF270) for DR80 and DY8. The study also tested microfilter paper (MF) under 100 KPa to reject DR80 and DY8. The pH, operating pressure, and dye concentration of the original solution determine dye rejection and permeate flow. The investigation shows that NF90 and NF270 reject DR80 at 98.98% and 98.30%, respectively, between 600–1000 KPa. Additionally, DY8 rejection averages 90.18 percent and 97.1 percent. The investigation also found that both dyes had the lowest permeate flux at 1.0 g/L and the greatest at 0.2 g/L. Comparisons show that microfilter paper rejects less than nanofiltration membrane. A predicament arises from the fact that the nanofiltration membrane operates at pressures six to ten times higher than those used in microfiltration, which typically functions at approximately 100 kPa. As a result, a direct comparison between the two filtration methods may lead to misleading conclusions.
Geochemical characteristics of dolomite: a case study from lower jurassic formations, imbricated zone, Iraqi Kurdistan region
Oct 5, 2024Journal Springer
Publisher Springer Nature Link
DOI 10.1007/s13146-024-01012-w
Issue 99
Volume 39
The geochemical characteristics and origin of Lower Jurassic dolomites from the Sarki and Sehkaniyan formations in the Imbricated Zone of Northern Iraq were investigated through analysis of major, trace, and rare earth elements, as well as stable isotopes (carbon and oxygen). The consistent CaO and MgO contents, their positive correlation, and elevated Mg/Ca values suggest an early penecontemporaneous sedimentary origin for dolomitization. These dolomites exhibit low Fe, Mn, and Sr contents, along with moderately low Na levels. Furthermore, they display low total rare earth element (ΣREE) contents, indicating low formation temperatures and a lack of light rare earth element (LREE) enrichment, while relatively negative δ18O values dismiss the influence of hydrothermal fluids on dolomitization. The patterns of rare earth elements normalized to the Post-Archean Australian Shale (PAAS) standard reveal a depletion of LREE compared to heavy rare earth elements (HREE), along with distinct negative Ce and positive Eu anomalies in most dolomites. The δ13C and δ18O values of the dolomites exhibit lower values than the contemporaneous seawater of the Lower Jurassic, which suggest the role of organic matter degradation and influence of meteoric water, respectively. Based on the petrographic and geochemical characteristics, the dolomite of the Lower Jurassic formations was mainly formed in the near-surface penecontemporaneous stage with late diagenetic recrystallization especially for Sehkaniyan dolomite.