Adsorption of anionic dyes in aqueous solution using chemically modified barley straw

Abstract

An agricultural waste derived adsorbent was prepared by chemically modified barley straw with NaOH and a cationic surfactant hexadecylpyridinium chloride monohydrate (CPC). The prepared adsorbent, BMBS, was used for removal of anionic dyes; Acid Blue (AB40) and Reactive Blue 4 (RB4) from aqueous solution in a batch adsorption system. The adsorbent was characterized by FT-IR and elemental composition. The stability of CPC adsorbed on straw surface was also evaluated by exposing to aqueous solution. In adsorption tests, influence of operation parameters such as contact time, initial concentration and pH of solution on AB40 and RB4 uptake were investigated and discussed. The CPC was observed strongly attached to straw surface and removal percentage of AB40 and RB4 was increased with increasing in contact time. The adsorption of dyes on modified straw surface was favorable at high acidic condition and desorption was found relatively low upon exposing to the desorption agent (i.e water). Dynamic experiment revealed that the kinetic data fitted well to the pseudo-second-order model for both of the dyes. The isotherm study also indicated that RB4 and AB40 adsorption suited well with the Langmuir model, The maximum adsorption capacity determined from the Langmuir isotherm at 25 degrees C was 51.95 mg g(-1) and 31.5 for AB40 and RB4, respectively.

De-coloration of hazardous dye from water system using chemically modified Ficus carica adsorbent

“…The mechanism for the removal of MB by adsorption may be due to the migration of dye from the bulk of the solution to the surface of the adsorbent, diffusion of dye through the boundary layer to the surface, adsorption of dye at active sites on the surface of adsorbent and intraparticle diffusion of dye into the interior pore structure of the adsorbent. The boundary layer resistance may be affected by the rate of adsorption and increase in contact time, which may increase the mobility of dye species during adsorption [7,[58][59][60][61][62][63][64][65][66][67].…”

Utilization of magnetically responsive cereal by‐product for organic dye removal

“…In recent years, many studies have suggested that waste plant materials can be utilized as potential sources of cheap and easily available biosorbents for organic dyes, heavy metal ions, radionuclides or endocrine disruptors. Plant derivatives, such as wheat straw, barley straw, rice straw, spent grain, pumpkin husks, peanut husks, spent coffee grounds, spent tea leaves, sawdust, sugarcane bagasse and many others, have been successfully used for adsorption of water‐soluble organic dyes from water systems.…”

Removal of dyes from aqueous solutions by straw based adsorbents: Batch and column studies

“…Researchers have been trying to find ways to take advantages of straw [14,15]. One of the promising ways to use this precious bioresource is to produce straw-based adsorbents [16][17][18][19][20]. However, the adsorption capacity of unmodified straw is insignificant, since straw materials are deficient in free ionic groups, which would play an important role in removal of ionic dyes.…”