This  work  is  aimed  at  improving  the  ability  of  red  mud  to  remove  methylene  blue  from  aqueous solution. The efficiency of methylene blue (MB) removal by untreated red mud was compared to that of red mud neutralized with distilled water. The pH, surface charge, particle size distribution, chemical composition,  infrared  spectrometry  and  morphology  analyses  were  used  to  characterize  the adsorbents.  Batch  experiments  without  agitation  and  filtration  were  conducted  to  determine  the influence  of  contact  time,  solution  pH,  temperature,  initial  dye  concentration,  adsorbent  dose  and presence of Clˉ, SO₄²ˉ, HPO₄²ˉ and HCO₃ˉ on dye removal. Distilled water treated red mud (RMD) had improved adsorbent properties than raw red mud (RM). For all the parameters tested, RMD showed higher removals of MB compared to RM. The fitting order for tested isotherm models was: Langmuir >Dubinin–Radushkevich > Freundlich for RMD and Freundlich > Dubinin–Radushkevich > Langmuir for RM.  Monolayer  adsorption  capacities  of  RMD  and  RM  were  found  to  be  17.123  and  4.221  mg/L respectively.  Pseudo-second-order  kinetic  model  suited  well  than  other  tested  kinetic  models. Equilibrium was attained in 24 hours, and the order of shifting of equilibrium to the right as well as the rate of uptake is: MB on RMD > MB on RM. MB removal was found to be more endothermic, more spontaneous and more favourable on RMD than on RM. Desorption experiments using acetone gave good  results  up  to  four  cycles.  MB  can  easily  be  removed  from  waste  water  using  distilled  water neutralized red.Water modified red mud is relatively efficient as other used materials for MB removal (Table 5), so it was concluded that red mud modified with distilled water can be used for industrial applications in removing methylene blue from various real effluents released from various types of industries  such  as  chrome  plating,  textile  dyeing,  leather  tanning  and  photolithographic  industries. Furthermore,  red  mud  is  very  cheap  as  compared  to  other  adsorbents  so  easily  available.  Also modification of red mud with water is a cheaper process with no risk of introducing other chemicals on to it  as  opposed  to  other  neutralization  methods  that use  mineral  acid,  heat  and  other  chemicals. Distilled water neutralized  red mud is  more efficient in removing methylene blue from waste water than untreated red mud.

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