Adsorption effect and mechanism of dyes and lead by brewer’s yeast biomass

• Main Authors: Han Hui Lin, 林翰暉
• Other Authors: Tsai-Hua Kao
• Format: Others
• Language: zh-TW
• Published: 2014
• Online Access: http://ndltd.ncl.edu.tw/handle/03747424194389402261

碩士 === 輔仁大學 === 食品科學系碩士班 === 103 === Brewer’s yeast biomass (BYB), a secondary byproduct produced during brewing process, which contains spent hops and surplus yeast. The objectives of this study are to discuss the adsorption effect of BYB on dyes and heavy metal including methylene blue, malachite green, safranin O and lead. In addition, for elucidating the adsorption mechanism, several isotherm models, namely, Langmuir, Freundlich,Redlich-Peterson and. shifted square Langmuir. Results showed BET specific surface area, total pore volume and pore size of BYB was 1.3806 m2/g, 0.005248 cm3/g and 152.0347 Å, respectively. After adsorption of dyes, the intensity of the FTIR band corresponding to OH and C≣N decreased with increasing in C-N band, suggesting that these groups may be involved in dye adsorption by BYB. The weight of 1.67 g/L and 0.83 g/L BYB could effectively remove basic dyes and lead and reach adsorption equilibrium in a short time. The adsorption capacity of dye and lead was positively associated with pH. At low temperature (20-30oC), non-linear regression of equilibrium data showed good correlation with Freundlich model for safranin O and lead, while the Langmuir model provided a better fit with methylene blue and malachite green. The maximum adsorption capacities of methylene blue, malachite green and safranin O based on the Langmuir isotherm model were 212.05, 212.05, 76.77 and 106.88 mg/g, respectively. Likewise, the kinetics of malachite green, methylene blue and lead. adsorption was well described by pseudo-second-order equation, while the safranin O adsorption better fit with pseudo-first-order equation.experiment showed hydrochloric acid could release more adsorbate from BYB, but the readsorption activity will be inhibited due to the decomposition of BYB after treating by high concentration of HCl.