Isotherm, thermodynamic, kinetics and adsorption mechanism studies of methyl orange by surfactant modified silkworm exuviae

Adsorption for Dyes on Activation Carbons from Japanese Cedar Wood Prepared by Precarbonization and Two-stage Composite Activations with Wood Ash and Steam

“…As the dye molecules adsorbed on the ACs can be desorbed by DI water, the dye molecules adhere to the ACs by the weak bonds, e.g. Van der Waals force [59], and can be desorbed by HCl or NaOH, meaning the dye adheres to ACs through ion exchange [31], [58]. This study used DI water, HCl, and NaOH to study the desorption rate (E d ) of BY2 dye on P200-0.25-750, which was 0.9, 0.3 and 1.4%, respectively, and the E d of BG4 dye on P200-0.25-750 was 1.5, 0.5 and 1.7 % (not shown in Table).…”

“…According to the Ecological and Toxicological Association of the Dyestuffs Manufacturing Industry investigation of 4,000 kinds of dyes on the market, the half lethal dose value of over 90% of them is 2×10 3 mg/kg, where basic dyes and diazo direct dyes have the highest toxicity [26], [27]. In addition, there are more than 100 thousand kinds of dyes on the global market, where the total output is as high as 700 thousand MT/year [22], [28]- [30], as dyes are universally used in many industries, such as textile, paper-making, leather, food, printing, [22], [23], [30], [31]. The paper industry is the second largest user of dyes in the U.S., where ordinary colored paper accounts for 40%, primary pulp paper accounts for 20%, color card paper accounts for 20%, and medical paper accounts for 10%.…”

“…Therefore, industrial waste waters with dyes should be treated to meet discharge standards before being discharged into the environment. There have been multiple methods for removing dyes from wastewater, and ACs adsorption have high specific surface area, large adsorption volume, rapid adsorption dynamics, and relatively easy regeneration [34], thus, they can rapidly reduce the concentration of dyes in water [30], [31], [35], are applicable to various dyes [27], and are readily available and easily used [36], [37]. While they are more expensive than other adsorbents, they have good effectiveness, and are one of the key points of the present dye wastewater pollution prevention engineering.…”

Adsorption of Pb(II) from Solution using Peanut Shell as Biosorbent in the Presence of Amino Acid and Sodium Chloride

“…To investigate the Pb(II) adsorption rate, the kinetics of Pb(II) adsorption by peanut shells was modeled using the pseudo-first order and pseudo-second order equation (Bajpai et al 2012;Chen et al 2011). Pseudo-first order assumes that the rate is proportional to the number of unoccupied sites.…”

The Adsorption of Rhodamine B in Water by Modified Zeolites

“…With the development of the dyeing industry, a great deal of dye wastewater is produced in China every year (Chen, Zhao, Wu, & Dai, 2011;Hu, Chen, Ji, & Yuan, 2010). Dye wastewater generally has a complex composition, high chemical oxygen demand (COD), high chromaticity, biochemical-degradation-resistant organic matter, and significant variations in water quality with the amount of water.…”