الفهرس 
REVIEW OF LITERATUREOnly 14 pages are availabe for public view
 |  | from | 76 |  |  |
| | | from | 76 | | |
Abstract
Water pollution, particularly with rapid industrial growth, is one of the most stressful issues in our country. Getting rid of heavy metals has become complicated and costly and also, one of the most difficult challenges facing the water treatment sector in Egypt and the world was the high cost of treatment because it requires very expensive infrastructure and it is a part of the long plans of governments and institutions, as well as the cost of operating these plants.
This work was conducted for an economic, environmental, and efficient solution that using microcrystalline cellulose (McC) for wastewater treatment. where cobalt and cesium removal mechanism was studied by using Microcrystalline Cellulose and chemically modified microcrystalline cellulose by one of the low-molecular-weight organic acids such as Citric Acid (McC-CA), which are extra chelators for Cobalt and Cesium from aqueous solution and the removal of most harmful of their isotopes (60Co and 137Cs) also have been studied. Also, an engineered system was fabricated to study the removal efficiency of microcrystalline Cellulose for Total Suspended Solids (TSS).
To reach the desired degree of environmental safety and save the effort and time in this research, the Taguchi robust method was used to design experiments to optimize the factors affecting Cobalt and Cesium removal by using Microcrystalline Cellulose (Ion concentration, pH, adsorbent dosage, and contact time) through an orthogonal array ( OA) L16 = 44 using batch experiments technique.
The results illustrated the contribution of the factors for both Co (II) and Cs (II) by using (ANOVA), where the most efficient parameter was pH followed by the Ion concentration (C), then Sorbent Dose (D), and the last one was Contact Time (T). The optimum combination for Co (II) and Cs (I) adsorption was pH (5-6), C (1-50 mg.L-1), D (3-4 g.L-1), T (60-100 mins.), and the percent removal for Co (II) and Cs (I) was 74% and 88% respectively. Furthermore, when this combination was applied to 60Co and 137Cs the percent removal ranged from 96.01% to 90.28% for 60Co, and 100% to 94.25% for 137Cs.
Also, Taguchi’s robust method was used to optimize the factors affecting TSS removal by the engineered system using McC, (Flow rate, Weight of material, operating time) through an orthogonal array (OA) L9 = 33. the optimal combination for TSS removal was recognized as A1B3C1 Where, Flowrate (level 1 = 2 L.min-1, S/N = -1.96), Weight of material (level 3 = 1 Kg, S/N = -2.17), and Operating time (level 1 = 30 mins., S/N = -2.8) Consequently, and the optimal number of washing times was five times, which gives results of 88% TSS percent removal, which is equivalent to 49.2 mg.L-1. Taguchi approach has been used very effectively to optimize parameters and to improve the reliability according to contour plots and verification tests. The optimum dose of gamma radiation to sterilize the water produced from the engineered system was 20 KGy.
our findings suggested that (McC) is highly efficient in cobalt, cesium, and TSS removal from wastewater as well as the Taguchi approach is a proper strategy to optimize the adsorption parameters and gamma radiation is an effective technique in wastewater sterilization.