Removal of orange 16 reactive dye from aqueous solutions by waste sunflower seed shells

Abstract

In this work, the use of an agro-industrial waste, i.e., sunflower seed shells, was investigated as a sorbent for the removal of Orange 16 reactive dye from aqueous environments. Batch experiments were performed as a function of pH, sorbent dose, dye concentration, temperature and contact time. The percent dye removal increased with increasing sorbent dose and temperature of the aqueous solution, and decreased with increasing dye concentration; the required contact time was five hours. The Freundlich, Langmuir, Dubinin-Radushkevich and Tempkin adsorption isotherms were used to describe the equilibrium sorption data and to determine the corresponding isotherm constants. The thermodynamic parameters ?G, ?H and ?S were also determined. These parameters indicated that the sorption of reactive dye onto sunflower seed shells was a spontaneous, endothermic and entropy-driven process. The kinetic data were evaluated by pseudo-first order, pseudo-second order and intra-particle diffusion kinetic models. The results of the kinetic study indicated that the sorption of Orange 16 reactive dye onto sunflower seed shells is a complex process and both chemical surface sorption and intraparticle diffusion contribute to the rate-limiting step. Therefore, the sunflower seed shell showed itself to be a promising cheap sorbent for the decolourization of aqueous coloured solutions or effluents.

Adsorption of reactive Orange 4 on sesame stalks. Modeling, kinetics and equilibrium

“…Each of the design parameters was investigated at five different values as shown in Table 2. We designed our experiments to obtain a quadratic model consisting of 2 4 trials plus a star configuration and six center points. Then, the results of the CCD were used to fit a quadratic equation by a multiple regression procedure.…”

“…In particular, the discharge of dye-containing effluents into water is undesirable due to their color and because decomposition products of many dyes have toxic, carcinogenic, or mutagenic effects on living organisms. For example, it was reported that some carcinogens such as benzidine, naphthalene, and other aromatic compounds, originated from dyes [3,4].…”

“…Sesame is an important agricultural crop in Turkey. Currently, sesame crop is cultivated in a total area of 5.1×10 4 ha, and 2.8×10 4 t of the crop are produced per year in Turkey. Unfortunately, the stalks of this crop are not used for any other beneficial applications, thus their usefulness as bio sorbents has been considered.…”

Fito Pengolahan untuk Dekosentrasi Warna Rhodamin B, Metilen Biru dan Metil Violet dengan Tumbuhan Air Eichhornia crassipes

“…Pada industri tersebut, zat warna ini memiliki berbagai polutan pada proses yang berbeda-beda [2]. Air limbah tekstil mencakup berbagai macam pewarna dan tambahan bahan kimia yang membuat tantangan lingkungan untuk industri tekstil tidak hanya untuk limbah cair tetapi juga komposisi kimianya dan polusi utama dalam air limbah tekstil berasal dari pencelupan dan finishing [3].…”

An Overview: Recent Development of Titanium Oxide Nanotubes as Photocatalyst for Dye Degradation

“…These negative impacts mainly attributed to the nonbiodegradable nature of the persistent organic dyes as well as their high colour intensity and are able to reduce aquatic diversity by blocking the passage of sunlight through the water [12]. In particular, the discharge of persistent organic dye effluents into the natural water resources or wastewater treatment systems is undesirable because most of these organic dyes released and their breakdown products are very toxic, carcinogenic, or mutagenic to life forms mainly due to the carcinogens, such as benzidine, naphthalene, and other aromatic compounds in the structure of persistent organic dyes [5,13,14]. These pollutants can cause irritation of the eyes, skin, respiratory tract, sore throat, asthma, and allergic contact dermatitis [15].…”