Novel functionalized polymeric flocculants based on polyacrylamide grafted carboxymethylstarch (C... more Novel functionalized polymeric flocculants based on polyacrylamide grafted carboxymethylstarch (CMSg-PAM) have been successfully synthesized via conventional method (using ceric ammonium nitrate as free radical initiator, in an inert atmosphere) as well as by using microwave irradiation ('microwave initiated' synthesis). Under optimal grafting conditions, 50% grafting has been observed in case of the microwave irradiation based method and 47% grafting has been observed in case of the conventional process. The synthesized graft copolymers have been characterized by elemental analysis, FTIR spectroscopy, intrinsic viscosity measurement, molecular weight determination, 13 C NMR spectroscopy and scanning electron micrograph (SEM); taking carboxymethylstarch (CMS) as reference. The effects of reaction parameters onto the percentage of grafting have been studied. Further, the applicability of these grafted polymers as flocculants for the treatment of municipal sewage wastewater has also been investigated.
International journal of biological macromolecules, 2013
Synthesis of graft copolymers under the influence of microwave radiation alone is a rapid, effici... more Synthesis of graft copolymers under the influence of microwave radiation alone is a rapid, efficient, clean, cheap, convenient, energy-saving and green method. Grafting of poly(2-hydroxyethylmethacrylate) on agar backbone was carried out under the influence of microwave radiation. The synthesis is optimized in terms of percentage grafting and intrinsic viscosity, by varying the microwave irradiation time and monomer (2-hydroxyethylmethacrylate) concentration. The synthesized graft copolymers have been characterized by intrinsic viscosity measurement, FTIR spectroscopy, UV-spectroscopy, elemental analysis (C, H, N, & S), thermal studies and scanning electron microscopy (SEM). Flocculation efficacy of the synthesized graft copolymers was studied in 0.25% kaolin and 1% coal fine suspension, through 'jar test' procedure. Further, flocculation efficacy of the best grade, coagulant (alum) and agar were studied for possible application in remediation of metals from river water.
International journal of biological macromolecules, 2013
Carboxymethyl inulin (CMI) has been synthesized by incorporation of carboxymethyl groups in the i... more Carboxymethyl inulin (CMI) has been synthesized by incorporation of carboxymethyl groups in the inulin framework; by reacting inulin with sodium salt of monochloro acetic acid (SMCA) in presence of sodium hydroxide. The resulting carboxymethylated product, with different degrees of substitution, has been confirmed through various physicochemical characterization techniques, such as intrinsic viscosity measurement, elemental analysis (C, H, N and O), FTIR spectroscopy, thermogravimetric analysis (TGA) and scanning electron microscopy (SEM) studies. Flocculation efficacy of various grades of CMI, have been studied in kaolin suspension and then in municipal wastewater, in relation to inulin (parent polysaccharide). This has been done utilizing jar-test procedure towards possible application as a flocculant for waste water treatment.
Cationic cassia was synthesized and characterized. Flocculation dosage was optimized for two diff... more Cationic cassia was synthesized and characterized. Flocculation dosage was optimized for two different green algae. Flocculation mechanism was hypothesized. Cationic cassia was proved to be a better flocculant than cassia. a b s t r a c t Green unicellular microalgae have a capacity to entrap CO 2 to increase their biomass through photosynthesis and are important for the value added product. The presence of COOH and NH 2 groups are responsible for imparting negative zeta value. The present work emphasizes on the synthesis of cationic cassia (CCAS) by the insertion of quaternary amine groups onto the backbone of cassia (CAS) from N-3-Chloro-2-hydroxypropyl trimethyl ammonium chloride (CHPTAC) which was further characterized via FTIR, SEM, elemental analysis and intrinsic viscosity. The optimal dosage of the synthesized cationic cassia is used to flocculate two different green fresh water algae viz. Chlamydomonas sp. CRP7 and Chlorella sp. CB4 were evaluated. 80 and 35 mg L À1 was optimized dose for dewatering of above algae, respectively.
A new resin is prepared by coupling amberlite XAD-4 with salicylic acid through an azo spacer. Th... more A new resin is prepared by coupling amberlite XAD-4 with salicylic acid through an azo spacer. Then the polymer support was coupled with cystein. The resulting sorbent has been characterized by FT-IR and elemental analysis and studied for adsorption and kinetic behavior of aspartic acid on the modified amberlite XAD-4. The optimum pH value for sorption of the amino acid was 8.5. The sorption capacity was found to be 5.31 mmol g −1 of resin for aspartic acid. The modified resin can be reused for 20 cycles of sorption-desorption without any significant change in sorption capacity. A recovery of 99 % was obtained for the aspartic acid with 0.5 M nitric acid as eluting agent. Adsorption data were modeled using the pseudo-first-order, pseudo-second-order and intra-particle diffusion kinetics equations. The rate constants of pseudo-first-order, pseudosecond-order adsorption and intra-particular diffusion were found 1.68 × 10 −2 min −1 , 1.14 × 10 −5 min −1 mg −1 g and 59.62 mg g −1 min −1/2 , respectively.
Novel functionalized polymeric flocculants based on polyacrylamide grafted carboxymethylstarch (C... more Novel functionalized polymeric flocculants based on polyacrylamide grafted carboxymethylstarch (CMSg-PAM) have been successfully synthesized via conventional method (using ceric ammonium nitrate as free radical initiator, in an inert atmosphere) as well as by using microwave irradiation ('microwave initiated' synthesis). Under optimal grafting conditions, 50% grafting has been observed in case of the microwave irradiation based method and 47% grafting has been observed in case of the conventional process. The synthesized graft copolymers have been characterized by elemental analysis, FTIR spectroscopy, intrinsic viscosity measurement, molecular weight determination, 13 C NMR spectroscopy and scanning electron micrograph (SEM); taking carboxymethylstarch (CMS) as reference. The effects of reaction parameters onto the percentage of grafting have been studied. Further, the applicability of these grafted polymers as flocculants for the treatment of municipal sewage wastewater has also been investigated.
Novel functionalized polymeric flocculants based on polyacrylamide grafted carboxymethylstarch (C... more Novel functionalized polymeric flocculants based on polyacrylamide grafted carboxymethylstarch (CMSg-PAM) have been successfully synthesized via conventional method (using ceric ammonium nitrate as free radical initiator, in an inert atmosphere) as well as by using microwave irradiation ('microwave initiated' synthesis). Under optimal grafting conditions, 50% grafting has been observed in case of the microwave irradiation based method and 47% grafting has been observed in case of the conventional process. The synthesized graft copolymers have been characterized by elemental analysis, FTIR spectroscopy, intrinsic viscosity measurement, molecular weight determination, 13 C NMR spectroscopy and scanning electron micrograph (SEM); taking carboxymethylstarch (CMS) as reference. The effects of reaction parameters onto the percentage of grafting have been studied. Further, the applicability of these grafted polymers as flocculants for the treatment of municipal sewage wastewater has also been investigated.
International journal of biological macromolecules, 2013
Synthesis of graft copolymers under the influence of microwave radiation alone is a rapid, effici... more Synthesis of graft copolymers under the influence of microwave radiation alone is a rapid, efficient, clean, cheap, convenient, energy-saving and green method. Grafting of poly(2-hydroxyethylmethacrylate) on agar backbone was carried out under the influence of microwave radiation. The synthesis is optimized in terms of percentage grafting and intrinsic viscosity, by varying the microwave irradiation time and monomer (2-hydroxyethylmethacrylate) concentration. The synthesized graft copolymers have been characterized by intrinsic viscosity measurement, FTIR spectroscopy, UV-spectroscopy, elemental analysis (C, H, N, & S), thermal studies and scanning electron microscopy (SEM). Flocculation efficacy of the synthesized graft copolymers was studied in 0.25% kaolin and 1% coal fine suspension, through 'jar test' procedure. Further, flocculation efficacy of the best grade, coagulant (alum) and agar were studied for possible application in remediation of metals from river water.
International journal of biological macromolecules, 2013
Carboxymethyl inulin (CMI) has been synthesized by incorporation of carboxymethyl groups in the i... more Carboxymethyl inulin (CMI) has been synthesized by incorporation of carboxymethyl groups in the inulin framework; by reacting inulin with sodium salt of monochloro acetic acid (SMCA) in presence of sodium hydroxide. The resulting carboxymethylated product, with different degrees of substitution, has been confirmed through various physicochemical characterization techniques, such as intrinsic viscosity measurement, elemental analysis (C, H, N and O), FTIR spectroscopy, thermogravimetric analysis (TGA) and scanning electron microscopy (SEM) studies. Flocculation efficacy of various grades of CMI, have been studied in kaolin suspension and then in municipal wastewater, in relation to inulin (parent polysaccharide). This has been done utilizing jar-test procedure towards possible application as a flocculant for waste water treatment.
Cationic cassia was synthesized and characterized. Flocculation dosage was optimized for two diff... more Cationic cassia was synthesized and characterized. Flocculation dosage was optimized for two different green algae. Flocculation mechanism was hypothesized. Cationic cassia was proved to be a better flocculant than cassia. a b s t r a c t Green unicellular microalgae have a capacity to entrap CO 2 to increase their biomass through photosynthesis and are important for the value added product. The presence of COOH and NH 2 groups are responsible for imparting negative zeta value. The present work emphasizes on the synthesis of cationic cassia (CCAS) by the insertion of quaternary amine groups onto the backbone of cassia (CAS) from N-3-Chloro-2-hydroxypropyl trimethyl ammonium chloride (CHPTAC) which was further characterized via FTIR, SEM, elemental analysis and intrinsic viscosity. The optimal dosage of the synthesized cationic cassia is used to flocculate two different green fresh water algae viz. Chlamydomonas sp. CRP7 and Chlorella sp. CB4 were evaluated. 80 and 35 mg L À1 was optimized dose for dewatering of above algae, respectively.
A new resin is prepared by coupling amberlite XAD-4 with salicylic acid through an azo spacer. Th... more A new resin is prepared by coupling amberlite XAD-4 with salicylic acid through an azo spacer. Then the polymer support was coupled with cystein. The resulting sorbent has been characterized by FT-IR and elemental analysis and studied for adsorption and kinetic behavior of aspartic acid on the modified amberlite XAD-4. The optimum pH value for sorption of the amino acid was 8.5. The sorption capacity was found to be 5.31 mmol g −1 of resin for aspartic acid. The modified resin can be reused for 20 cycles of sorption-desorption without any significant change in sorption capacity. A recovery of 99 % was obtained for the aspartic acid with 0.5 M nitric acid as eluting agent. Adsorption data were modeled using the pseudo-first-order, pseudo-second-order and intra-particle diffusion kinetics equations. The rate constants of pseudo-first-order, pseudosecond-order adsorption and intra-particular diffusion were found 1.68 × 10 −2 min −1 , 1.14 × 10 −5 min −1 mg −1 g and 59.62 mg g −1 min −1/2 , respectively.
Novel functionalized polymeric flocculants based on polyacrylamide grafted carboxymethylstarch (C... more Novel functionalized polymeric flocculants based on polyacrylamide grafted carboxymethylstarch (CMSg-PAM) have been successfully synthesized via conventional method (using ceric ammonium nitrate as free radical initiator, in an inert atmosphere) as well as by using microwave irradiation ('microwave initiated' synthesis). Under optimal grafting conditions, 50% grafting has been observed in case of the microwave irradiation based method and 47% grafting has been observed in case of the conventional process. The synthesized graft copolymers have been characterized by elemental analysis, FTIR spectroscopy, intrinsic viscosity measurement, molecular weight determination, 13 C NMR spectroscopy and scanning electron micrograph (SEM); taking carboxymethylstarch (CMS) as reference. The effects of reaction parameters onto the percentage of grafting have been studied. Further, the applicability of these grafted polymers as flocculants for the treatment of municipal sewage wastewater has also been investigated.
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