الفهرس 
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Abstract
The main aim of this thesis is to investigate the suitability of using some Egyptian agriculture wastes and its cellulosic derivatives as substrates for dye adsorption from its the raw and/or the alkali
treated samples decreases the adsorption of the colour by the substrate.
3. It is also clear from the data obtained that the magnitude of dye adsorption in case of ultrasonic is relatively higher than mechanical shaking irrespective of the nature of reactive dye used. For example in case of reactive blue 19 the maximum dye adsorption was 63.80/0 and 53.3% on using ultrasonic and mechanical shaking respectively.
4. It was found that as the concentration of the dye increases from 0.01 to 0.5g / 100ml, the magnitude of adsorption increases regularly, but the % colour removal decreases. This phenomenon holds true regardless of: (a) the nature or the reactive dye used, (b) the nature of the substrate and (c) the technique applied i.e. either mechanical stirring or ultrasonic. For example in case reactive blue 19 on using native rice straw for the samples conducted via mechanical stirring the adsorption increases regularly from 0.084 to 1.4, while the % colour removal decreases regularly from 53.30/0 to 14.90/0 by increasing the dye concentration from 0.01 to 0.5g / 100mI.
5. The % colour removal increases by increasing the time of treatment to reach its maximum then levels off or slightly decreases. This phenomenon holds true regardless of the nature of the colour used and / or the technique adopted, i.e. either in case of using mechanical stirring or ultrasonic.
6. It is also clear from the data that ultrasonic treatment highly increases the rate of dye adsorption of pure cellulose pulp derived from rice straw. Since, the magnitude of the adsorbed dye, expressed as % colour removal, is higher and the time to reach to the maximum
adsorption is shorter in case of ultrasonic compared with mechanical stirring.
7. The decrease in the dye adsorption by increasing the
temperature may be due to one or both of the following: (a) as the temperature increases the rate of hydrolysis of the reactive dye increases and hence the number of the reactive molecules which adsorbed and chemically bounded to cellulose decreases, (b) as the temperature increase, the mobility of the dye molecules increases, For example in case of reactive blue19 for the sample conducted using mechanical shaking the % colour removal decrease from 55.5%, to 52.7%, to 44.4%, to 20.5% by increasing the temperature from 300( to 40°(, to 50°(, to 600( respectively. The same trend could be observed for the same dye in case of
using ultrasonic.
8. It is obvious from the results obtained that % colour
removal depends on: (a) the nature of the dyestuff used, (b) the degree of purity of the adsorbent, and (c)
the technique applied
Synthesis and utilization of partially carboxymethyl cellulose derived from rice straw as dye adsorbents
The main aim of this part was to synthesis partially carboxymethylated derivatives from rice straw cellulosic pulp and to utilize the pulp with their partially carboxymethylated derivatives as adsorbent substrates for different classes of
dyestuffs.
The results obtained from these investigations can be summarized as follows:
1- As the amount of monochloro acetic acid increases from 5 to 1 Og/l OOg cellulose, the D.S. increase s from 0.09 to 0.14
2- Increasing the amount of adsorbent, l.e .. partially carboxymethyl derivatives, is accompanied by an increase in the % colour removal to reach to a maximum after which it either remain constant or decreases. This phenomenon holds true regardless of the 0.5., the nature of the reactive dye used, or the technique
applied.
3- Increasing the 0.5. causes an increase of the COOH
groups. The latter ionize in the solution into-COO and Na + which causes an increase in the negative charge on the substrate. Since the reactive dye acquire negative charge too hence the rate of dye adsorption decrease.
4- The rate of dye adsorption increases by increasing the time of adsorption to reach to a maximum after which it shows slight decrement or remains constant. However, the time of adsorption to reach the maximum value and magnitude of the % colour removal at the maximum adsorption depends on the nature of the colour and the adsorbent used as well as the technique applied.
5- It was found that in all cases as the dye concentration increase from 0.01 to 0.5gm, % the percent dye adsorption decreases regularly. This may be due to either: (a) aggregation of the dye molecules which increases as the concentration increases, or (b) the decrease in the mobility of the dye molecules as the concentration increases. F or example on using carboxymethyl derivative of D.S.0.09 and reactive blue 19 for the samples conducted using mechanical shaking, the % colour removal decreases from 76.60/0 to 62.90/0 to 54.60/0 to 42.80/0 as the concentration of the dye increases from O.Olg to 0.04g to 0.2g to 0.5g
respectively.
6- It is obvious from the results that the % decreases in
colour depends on: (a) the nature of the dyestuff used, (b) the 0.5. of the adsorbent and, (c) on the technique applied. It is clear from the data that on using carboxymethyl derivative of 0.5.0.09 for the samples conducted under mechanical stirring the % colour removal incase of basic dyes is higher than that of acid dye. where the percent colour removal follows the eider.
Basic green > Basic yellow > acid green > acid blue respectively.
The same trend could be observed in case of using
carboxymethyl derivative of 0.5.0.14 for the samples conducted either via mechanical stirring or ultrasonic
technique.
Synthesis and utilization of partially carbamated cellulose derivative from rice straw as dye adsorbents
The main aim of this part was to synthesis partially carbamated derivatives from rice straw and to utilize the cellulosic pulp with their partially carbamated derivatives as adsorbent substrates for dyes.
The results obtained from these investigations can be summarized as follows:
1- As the amount of urea increases from 10 to 20g/l OOg cellulose the N content expressed as %N 0.13 to 0.16
2- In most cases increasing the carbamate groups expressed %N on the cellulose chains is accompanied by an increase in % colour removal. For example in case of reactive blue19 for the sample conducted using ultrasonic, the maximum % colour removal was found to be 86.1% and 75.5% for the samples prepared using 20g or 109 ureal 100g (N% 0.16 and 0.13) cellulose respectively; i.e. which contain greater amounts of carbamate group.
3- It is clear from the obtained results that the % colour removal as well as the time to reach the maximum colour removal depend on: (a) the nature of the reactive dye used, (b) the degree of carbamation expressed as % N and (c) the technique applied.
4- It is also obvious from the data that on using carbamate derivative of low % N the magnitude of the percent colour removal was 81.5% and 67.8% on using reactive violet5 and 75.5% and 58.8% on using reactive blue19
for the sample acquire the relatively higher % N it was 86.1 % and 77.7% on using reactive blue19 on using either ultrasonic or mechanical shaking respectively.
5- It can be concluded that in all cases, i.e. irrespective of the nature of colour used or the technique applied, the magnitude of the adsorbed colour depends on the % N where as %N increases the % colour removal increases too. This is expected since amino group acquire +ve charge and the reactive dye acquire -ve charge. As the amount of amino groups increases the capacity of the
adsorbent increases.
6- As the concentration of the dye increases from 0.01 to
0.5g/ 100ml, the % colour removal decreases regularly. The same trend was also observed on using the original, alkali treated, cellulosic pulp or carboxymethyl derivatives of rice straw and can be explained on the same basis, as previously mentioned, as the concentration of the dye increases the rate of dye aggregation increases and its mobility decreases hence
the adsorbed dye decreases