Preparation of water soluble chitosan blendmers and their application to removal of heavy metal ions from wastewater

Abstract

High purity water soluble chitosans (WsCs) were employed as a flocculant to remove heavy metal ions from wastewater of industrial plating wastewater treatment complex. Their weight average molecular weights and polydispersities were 272,000~620,000 g/mol and 1.4~1.9 range, respectively and were readily soluble in water in the pH range of 3~11. Heavy metal ions such as chromium, iron and copper were removed well by WsCs. When WsCs was blended with either sodium N,N-diethyldithiocarbamate trihydrate (SDDC T ) or sodium salicylate (SS C ), the removal efficiency was further increased primarily due to the excess amount of hydrophilic sulfonic and carboxylic groups. Especially, in the case of WsCs-SS C the remaining chromium and copper concentrations were 0.1 mg/L and 9.5 mg/L, which are 1/15 and 1/3 compared with that of pure WsCs, respectively. The former is within the acceptable limit, but the latter is not. Therefore, the effective copper flocculant remains to be studied.

Chitosan Performance of Shrimp Shells in The Biosorption Ion Metal of Cadmium, Lead and Nickel Based on Variations Ph Interaction

“…The results of chitosan characterization are presented in Table 2, the following: Table 2 presents that the chitosan content obtained is in line of the international standards, [9,22]. The solubility of chitosan in 2 % glacial acetic acid solution is one of chitosan quality assessment parameters isolated from shrimp shell, [1,20,23].…”

“…The number of amine groups in chitosan is the success of the isolation method. The -NH 2 group on chitosan is seen through the reaction of the purple ninhydrin solution indicating a reduction reaction at pH 6 to 8 forming a bonding compound between ninhydrin and hydrinadantin, [2,9]. The adsorption capacity of chitosan to metal ions Cd, Pb and Ni as shown in Table 3 and Figure 1, is done based on pH variation of interaction medium giving an idea that the pH of the interaction medium influences chitosan ability in absorbing certain metal type.…”

“…Chitin is a polysaccharide group, a linear chain polymer and high molecular weight [β-(1-4) -2-acetamide-2-deoxy-D-glucose], can be converted into chitosan through the stages deproteinize (addition of aqueous NaOH), stage of demineralization ( addition of low concentration HCl) and deacetylation stage (strong base reaction NaOH 50 %), [6]. The deacetylation reaction of chitin by removing the acetyl group (CH 3 CONH-) produces chitosan polymer [β-(1-4) -2-amine-2-deoxy-D-glucose], molecular formula (C 6 H 11 NO 4 )n, polycationic, high and reactive solubility, [2,7,8,9]. Chitosan is a yellowish-white amorphous solid polymer, potentially used as a heavy metal adsorbent by the mechanism of free electron-donor pair (Lewis bases) in hydroxy group (-OH) and amine (-NH 2 ) to form pseudobonds with heavy metal cations resulting in a chitosanmetal weight of complex, [7,10].…”

Characterization of Capsaicin-Loaded Nanoemulsions Stabilized with Alginate and Chitosan by Self-assembly

“…Next, the chitosan (degree of deacetylation 93%, molecular weight 330,000) was dissolved in a mixed aqueous solution of 20% hydrochloride solution and distilled water, after which the mixture was adjusted to pH=5.6 and stirred for 3 h. The reaction mixture was then subjected to a continuous membrane filtration process, after which a permeate was freeze-dried (Seo and Toshio 2002). Alginate sodium salt(from brown algae, 3,500 cp, 2%, 25°C) was purchased from Sigma Chemical Co. (St. Louis, MO, USA).…”

Chitosan-PVP-nano silver oxide wound dressing: In vitro and in vivo evaluation

“…Chitosan has many advantageous biological properties in the application as a wound dressing, namely biocompatibility, biodegradability, hemostatic activity, anti-infectional activity and property to accelerate wound-healing [1][2][3][4][5][6][7]. Chitosan influence positively in to various steps of complex wound healing process.…”