Synthesis and Characterization of Cellulosic Ether Derivatives from Mesquite

Abstract

Cellulose pulpwith yield of 35% and 92% alpha cellulose was extracted from mesquite tree wood, by anthraquinone Kraft pulping method and bleached by hypochlorite. The extracted cellulose was characterized by FT-IR, XRDspectr- oscopy, and thermal analysis (TGA/DTG/ DTA) and confirmed the cellulose structure. The extracted cellulosewas used for preparing carboxymethylcellulose(CMC),hydroxypropylcellulose (HPC), and methylcellulose (MC) cellulosic ether derivativeswith yield of, 190%,and 160.61% and, 115.5% weighthike respectively. The prepared cellulose ether derivatives products were characterized by FT-IR, XRD, NMR spectroscopy and thermal analysis (TGA/DTG/ DTA)and confirmed the ether derivatives structure. The optimum conditions for preparing ether derivatives products were investigated. For CMC,the results were, 40 % NaOH, 7g monochloroaceticacid (MCA), at 55 C for 3.5 hours reaction time,and the degree of substitution (DS) was 1.3.For HPC, ,the results were,2.8 ml propylene oxide(PO) /g cellulose, for 6 hours at 70 C,and thedegree of substitution (DS) was1.72 . For MC,the results were, 300 %( v /w cellulose)dimethylsulfate (DMS) concentration,for 5 hours at 50 C and the degree of substitution (DS) was 1.68. Solubility of prepared ether derivatives products were investigated and found to be 6% , 7% , and 3% for CMC, HPC and MC respectively.. Viscosityof prepared ether derivatives products were investigated and found to be 2500 cPs, 2000 cPs, and 1500cPs for CMC, HPC and MC respectively. Thermal stability of the prepared products was investigated and found that the products have acquired high thermal stability compered to cellulose. The prepared ether derivatives, in optimum conditions, were used as stabilizers for preparing, carboxymethylcellulose/Fe3O4, hydroxypropylcelluolse/Fe3O4, methylcellulose/Fe3O4, magnetite nanocomposite by co-precipitation, and characterized byFT-IR, XRD spectroscopy, and thermal analysis (TGA/DTG/ DTA)and confirmed the magnetite composite structure. The prepared magnetite nanocomposite, of carboxymethyl cellulose/Fe3O4 nanocomposite,was tested for removal of dyes in aqueous solutions using methylene blue solution. The optimum conditions for methylene blue(MB) dye adsorption capacity by 0.05 g of prepared carboxymethylcellulose/Fe3O4 nanocomposite were investigated which were, PH 7, rapid at~40 min slowed at~ 40t0~60 min and reached plateau at 60 min, increased with increasing of dye concentration up of 1500 ppm. The adsorption kinetics of carboxymethylcellulose/Fe3O4 nanocomposite for (MB) were studied and found to be compatiblewith the second-order kinetics model.