| As a part of industrial wastewater, dye wastewater is one of the most important ones.Therefore, a reasonable and effective treatment method for choice that makes a significantcontribution to ecological environment protection. Relatively pure humic acids are extractedfrom lignite collected and they are made into dissolved and flocculent state. It studies the bindingand sorption of dyes from wastewater on the humic acid from lignite and influence factors. FTIRspectra is used to discuss mechanism. The experimental findings indicated as follows.Sorption of dyes Acid Red B, G,3R from wastewater on flocculent humic acid shows thatthe rates of adsorption can nicely conform to the pseudo-second-order kinetics, and theadsorption isotherm of dyes should follow Freundlich model well. Adsorption equilibrium ofdyes on flocculent humic acid could be reached respectively within4h,5h,3h; The most idealtime for binding of dyes onto dissolved humic acid is found to be15min, and adsorptionequilibrium of them could be reached respectively within12h,15h,12h; The removal rate ofdyes tends to increase with the reduction of pH value. Weak base is beneficial to binding of AcidRed B, G,3R on dissolved humic acid (pH=8). Strong acid is good for sorption of dyes onflocculent humic acid (pH=0.5). A higher removal rate of dye Acid Red B, G,3R can be gainedat more dosage of humic acid added in the solution. A higher adsorption of Acid Red B, G canbe obtained under higher ion strength (NaCl) of the solution. But the adsorption of Acid red3Rcan’t be affected by ion strength (NaCl). Adsorption capacity increase obviously with increasingfraction of humic acid. FTIR spectra of humic acid and humic acid-dye complexes show thathumic acid contains alkyl, hydroxyl, carboxyl and aromatic group. The binding and sorptionmainly happens on these groups. This research provides theoretical basis and technical supportfor the sorption of dye from wastewater on humic acid from lignite. |
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