Removal of dyes using agricultural waste as low-cost adsorbents: a review

Abstract

Color removal from wastewater has been a matter of concern, both in the aesthetic sense and health point of view. Color removal from textile effluents on a continuous industrial scale has been given much attention in the last few years, not only because of its potential toxicity, but also mainly due to its visibility problem. There have been various promising techniques for the removal of dyes from wastewater. However, the effectiveness of adsorption for dye removal from wastewater has made it an ideal alternative to other expensive treatment methods. In this review, an extensive list of sorbent literature has been compiled. The review evaluates different agricultural waste materials as low-cost adsorbents for the removal of dyes from wastewater. The review also outlines some of the fundamental principles of dye adsorption on to adsorbents.

Factor Affecting Textile Dye Removal Using Adsorbent From Activated Carbon: A Review

“…Due to deposition of dyes on the available adsorption site on adsorbent material, any further increase in contact time will not increase the uptake [5]. At this point, the amount of dye desorbing form the adsorbent is in a state of dynamic equilibrium with the amount of dye being adsorbed onto the adsorbent.…”

“…Synthetic dyes gained huge popularity in textile and dyeing process because of their stability to light, temperature, detergent and variety in colour [3]. In fact, it has reached nearly 100,000 different types of dyes and annually produce over 7.0x10 5 tonnes per year worldwide [3][4][5][6][7][8]. Loss of up to 40% dye during the dyeing process are the result of coloured wastewater that passed into the environment or treatment plants [10].…”

“…However, conventional activated carbon that been used today are expensive for a large scale of treatment [21][22][23]. Recently, the researchers has been focus on the development of low cost adsorbent for a full scale treatment [5,24,25]. Therefore, this review provide comprehensive information on the application of activated carbon for the treatment of dye and study the effect of adsorption factors towards dye removal.…”

“…Back then, benzidine-based dye are used to colour textile, leather, wood, paper, plastic, fur and cosmetic industries [33]. As for worldwide textile industries, dye are discharged more than 1000 tones/year into waste stream [5,34]. Consequently, these textile wastewater containing benzidine-based dye may cause major damage to ecosystem including loss of soil productivity, disturbing the oxygen transfers in water interface and also interrupt photosynthesis activity.…”

“…Activated carbon have extended surface area, high capacity of adsorption, higher surface reactivity degree and also micro-pore structure which is suitable in eliminating dye from wastewater [41][42][43]. However, treating wastewater by using conventional activated carbon that is available in the market are expensive [1,5,31,[43][44] and its regeneration are even costly [26]. Therefore, various raw material have been examined to produce activated carbon and each presents different properties as some previous research of adsorbent shown in Table 2.…”