Studies on structural, morphological, electrical and electrochemical properties of activated carbon prepared from sugarcane bagasse

T. Adinaveen,L. John Kennedy,J. Judith Vijaya,G. Sekaran 한국공업화학회 2013 Journal of Industrial and Engineering Chemistry Vol.19 No.5

Activated carbon composite was prepared from sugarcane bagasse. The X-ray diffraction revealed the evolution of crystallites of carbon and silica during activation at higher temperature. FTIR spectrum shows the presence of functional groups and silica in the carbon composite. The morphology of the carbon sample was determined by SEM. The surface area, pore volume and pore size distribution of carbon composites were measured. The dc conductivity was determined and conductivity at room temperature was found to increase from 10.22 x10-3 to 25.131 x 10-3 S cm-1. The samples show good electrochemical property and the specific capacitance in the range of 92–340 F g-1.

가죽의류 제조공업 1차 화학슬러지로부터 건설자재원료의 생산

( Sekaran¸ G. ),( Gnanamani¸ A. ),( Rajamani¸ S. ),( Sadulla¸ S. ),( T. Ramasami ) 한국폐기물자원순환학회 2002 APLAS Vol.2002 No.2

가죽의류 제조공업으로부터 발생된 폐수는 COD 3094mg/l, BOD 980mg/l, TOC 1133mg/l, VFA 840mg/l, 게다가 pH 산도 5.65와 타닌 50mg/l 를 함유한다. 폐수의 물리적처리 구성은 화학적 처리 COD 1890mg/l, BOD 690mg/l, TOC 734mg/l, 타닌 10mg/l 로 감소하였다. 슬러지는 가죽의류제조 1ton당 800kg 이 발생한다. 1차 화학슬러지로부터 다른 pH의 침출수는 BOD 100-240mg/l, COD 351-2544 mg/l, 타닌 44-161 mg/l, Cr3+ 0.5-19 mg/l, 철 2-25 mg/l, pH1-11 로 나타났다. 토양 침출수의 환경부하는 batch 와 고정식 흡착실험에 의해 조사 되었다. 침출수의 요소는 공동확산작용, 활성에너지, COD, TDS, Chromium, 타닌에 의해 결정되어졌다. 1차 화학슬러지에서 생산된 석회가루는 시멘트, 비산재,석회의 같은 비율의 무게로 혼합하였다. 혼합구성; 생석회슬러지: 점토: 시멘트, 생석회슬러지: 비산재 : 시멘트, 생석회슬러지 : 비산재: 석회 : 시멘트, 생석회슬러지 : 비산재 : 점토 : 시멘트, 생석회슬러지 : 비산재 : 점토: 시멘트 : 석회. 위의 혼합으로 주조한 벽돌은 습한 대기상태에서 28일간 양생 되었다. 벽돌은 중금속과 유기물에 관계된 다른pH상태에서 침출수 특성과 압축강도 시험을 하였다. 1차 화학슬러지에서 석회와 벽돌제조의 처분의 경제성에 대해 토의한다. Wastewater generated from garment leather manufacturing industry contained COD 3094mg/l, BOD 980mg/l, TOC 1133mg/l, VFA 840mg/l, in addition to acidic pH 5.65 and tannin 50 mg/1. Physical treatment of wastewater consisted of equalization cum settling followed by chemical treatment with Ferric Chloride to remove tannin and lime to neutralize the wastewater. COD was reduced to 1890, BOD to 690 mg/1 and TOC to 734 mg/1 and tannin to 10 mg/1. The sludge production was 800 Kg per ton of the garment leather manufactured. The leachates at different pH from the primary chemical sludge was characterized were BOD 100-240 mg/1, COD 351-2544 mg/1, Tannin 44-161 mg/1, Cr3+ the range of 0.5 - 19 mg/1 and Iron in the range of 2-25 mg/1 over the pH range of 1-11. The environmental impact of the leachates on soil was investigated under batch and fixed bed adsorption studies. The diffusion coefficient and energy of activation of the leachate components in terms of COD, TDS, Chromium and tannin were determined. The primary chemical sludge was calcined under controlled atmosphere in an electric furnace. The calcined product of the primary chemical sludge was blended by Portland cement, Fly ash, Lime in the following combination; Calcined sludge: Clay: Cement, Calcined sludge: Fly ash : Cement, Calcined sludge : Fly ash: Lime: Cement, Calcined sludge : Fly ash : Clay : Cement, Calcined sludge : Fly ash: Clay: Cement: Lime in fixed ratio by weight. The bricks casts from the above mixtures were cured for 28 days under controlled humid atmosphere. The bricks were tested for their compressive strength and leaching characteristics under different pH conditions with reference to heavy metals and organics. The economics of the disposal of primary chemical sludge through calcinations and brick making is discussed.

PRODUCTION OF CONSTRUCTIONAL MATERIAL FROM PRIMARY CHEMICAL SLUDGE GENERATED FROM A GARMENT LEATHER MANUFACTURING INDUSTRY

( Sekaran¸ G. ),( Gnanamani¸ A. ),( Rajamani¸ S. ),( Sadulla¸ S. ),( T. Ramasami ) 한국폐기물자원순환학회 2002 APLAS Vol.2002 No.1

Wastewater generated from garment leather manufacturing industry contained COD 3094mg/l, BOD 980mg/l, TOC 1133mg/l, VFA 840mg/l, in addition to acidic pH 5.65 and tannin 50 mg/l. Physical treatment of wastewater consisted of equalization cum settling followed by chemical treatment with Ferric Chloride to remove tannin and lime to neutralize the wastewater. COD was reduced to 1890, BOD to 690 mg/1 and TOC to 734 mg/1 and tannin to 10 mg/1. The sludge production was 800 Kg per ton of the garment leather manufactured. The leachates at different pH from the primary chemical sludge was characterized were BOD 100-240 mg/1, COD 351-2544 mg/1, Tannin 44-161 mg/1, Cr³⁺ the range of 0.5 - 19 mg/1 and Iron in the range of 2-25 mg/1 over the pH range of 1-11. The environmental impact of the leachates on soil was investigated under batch and fixed bed adsorption studies. The diffusion coefficient and energy of activation of the leachate components in terms of COD, TDS, Chromium and tannin were determined. The primary chemical sludge was calcined under controlled atmosphere in an electric furnace. The calcined product of the primary chemical sludge was blended by Portland cement, Fly ash, Lime in the following combination; Calcined sludge: Clay: Cement, Calcined sludge: Fly ash : Cement, Calcined sludge : Fly ash: Lime: Cement, Calcined sludge : Fly ash : Clay : Cement, Calcined sludge : Fly ash: Clay: Cement: Lime in fixed ratio by weight. The bricks casts from the above mixtures were cured for 28 days under controlled humid atmosphere. The bricks were tested for their compressive strength and leaching characteristics under different pH conditions with reference to heavy metals and organics. The economics of the disposal of primary chemical sludge through calcinations and brick making is discussed.

DISPOSAL OF LEACHATES COLLECTED FROM THE CO-DISPOSAL OF SOLID WASTE GENERATED IN A CHEMICAL INDUSTRY

( Gnanamani A. ),( Sekaran G. ),( Rajamani S. ),( Sadulla S. ),( Ramasaini T. ) 한국폐기물자원순환학회 2002 APLAS Vol.2002 No.1

Manufacture of dicarboxylic acid from the raw material benzene leaves behind a polymeric material which has very high tendency to solidify. The solidified product is dumped on the open ground as one of the suggested methods for the disposal. The land co-disposal of solid product is subjected to climatinc conditions leading to leaching of the compound into deep soil pit, constructed near the land co-disposal site. The solid waste was characterized by pH 2.11, BOD by 12000 mg/1, COD 38857 mg/1, TOC 19380 mg/1 and VFA 24170 mg/1. The poor biodegrdable nature of the leachate, indexed by BOD/COD ratio (0.31), renders the conventional treatment technologies followed for the degradation of components of leachate were ineffective and thus disposal problem remains unsolved. Hence, advanced wastewater treatment technology was the opted technology for the disposal of the leachate of the solid product. In the present investigation acidified dichromate, Fenton reagent and Hydrogen peroxide/activated carbon catalyst mixture were attempted to fission the intermolecular and intramolecular bonding in the polymeric compound. After cataytic oxidation with acidified dichromate the BOD and COD values were found to be 3900 and 6406 mg/1. However, cleavage of bonding in polymeric compound was accompanied with conversion of hexavalent chromium into trivalent chromium offering heavy metal contamination. Oxidation of leachate sample with Fenton reagent was able to reduce BOD and COD values respectively to 2100 mg/1 and 5441 mg/1. However, The treated compound had the evidence of heavy metal contamination. Solid waste samples were oxidised with hydrophilic mesoporous activated carbon/H₂O₂ mixture to obtain BOD and COD values respectively 2300 mg/1 and 5471 mg/1. The Activated carbon/H₂O₂ catalysed solid waste samples have recorded marked improvement in anaerobic biological treatment. After anaerobic biological treatment the BOD and COD values have been reduced to 300 mg/1 and 621 mg/1 respectively. Further reduction BOD and COD values were achived in aerobic biological treatment. The scheme of process followed for the treatment and the variables that control the catalytic oxidation process, and anaerobic treatment of catalytic oxidised sample is discussed.

화학공업 폐기물 혼합매립 침출수의 처분

( Gnanamani A. ),( Sekaran G. ),( Rajamani S. ),( Sadulla S. ),( Ramasami T. ) 한국폐기물자원순환학회 2002 APLAS Vol.2002 No.2

벤젠 원료로부터 디카르복시산의 생산시 견고하려는 경향성이 매우 높은 폴리머 물질을 발생시킨다. 이 견고한 생산품은 제안된 처분 방법의 일종인 지표에 버려진다. 고형 생산품의 지표 공동처분은 기후 조건에 의해 공동처분지 인근에 건설된 깊은 토양 피트로 화합물을 침출시키기도 한다. 고형폐기물은 pH 2.11, BOD 12,000 mg/L, COD 38,850 gni/L, TOC 19,380 mg/L 및 VFA 24,170 mg/L를 나타낸다. 생물학적 분해가 어려운 특성을 가지는 침출수는 BOD/COD 비가 0.31을 나타내며, 침줄수의 분해 요소에 따르는 재래식 처리 기술이 비효율 적이게 되어, 해결되지 않은 처분 문제가 남게 된다. 그러므로, 고형 생산품의 침출수 처리 기술에 고도 폐수처리 기술이 적용되었다. 현재의 연구는 산성 디클로메이트, 펜톤 산화제,H2O2/활성탄 촉매 혼합물이 폴리머 화합물 내의 intermolecular와 intramolecular 결합을 분열시키기 위해 시도되는 것이다. 산성 디클로메이트로 족매 산화된 후, BOD 및 COD 수치는 각각 3,900 mg/L, 6,406 mg/L를 나타내었다. 그러나, 폴리머 화합물내의 결합 분열은 6가 크롬에서 중금속 오염을 초래하는 3가 크롬으로의 변화를 가져왔다. 펜톤 산화제에 의한 침출수 시료의 산화는 BOD 및 COD 농도를 각각 2,100 mg/L, 5,441 mg/L로 낮출 수 있었다. 그러나, 처리된 화합물은 중금속에 오염된 것으로 나타났다. 고형 폐기물 시료는 친수성 중간형 다공 활성탄/H2O2 혼합물에 의해 산화되었으며, 이때의 BOD 및 COD 농도는 각각 2,300 mg/L, 5,471 mg/L를 나타내었다. 활성탄/H2O2로 의해 촉매화된 폐기물 시료는 혐기성 생물학적 처리기술의 향상을 가져왔다. 호기성 생물학적 처리 후 BOD 및 COD 농도는 각각 300 mg/L, 621 mg/L로 감소되었다. Manufacture of dicarboxylic acid from the raw material benzene leaves behind a polymeric material which has very high tendency to solidify. The solidified product is dumped on the open ground as one of the suggested methods for the disposal. The land co-disposal of solid product is subjected to climatinc conditions leading to leaching of the compound into deep soil pit, constructed near the land co-disposal site. The solid waste was characterized by pH 2.11, BOD by 12000 mg/1, COD 38857 mg/1, TOC 19380 mg/1 and VFA 2470 mg/1. The poor biodegrdable nature of the leachate, indexed by BOD/COD ratio (0.31), renders the conventional treatment technologies followed for the degradation of components of leachate were ineffective and thus disposal problem remains unsolved. Hence, advanced wastewater treatment technology was the opted technology for the disposal of the leachate of the solid product. In the present investigation acidified dichromate, Fenton reagent and Hydrogen peroxide/activated carbon catalyst mixture were attemted to fission the intermolecular and intramolecular bonding in the polymeric compound. After cataytic oxidation with acidified dichromate the BOD and COD values were found to be 3900 and 6406 mg/1. However, cleavage of bonding in polymeric compound was accompanied with conversion of hexavalent chromium into trivalent chromium offering heavy metal contamination. Oxidation of leachate sample with Fenton reagent was able to reduce BOD and COD values respectively to 2100 mg/1 and 5441 mg/1. However, the treated compound had the evidence of heavy metal contamination. Solid waste samples were oxidised with hydrophilic mesoporous activated carbon/H2O2 mixture to obtain BOD and COD values respectively 2300 mg/1 and 5471 mg/1. The Activated carbon/H2O2 catalysed solid waste samples have recorded marked improvement in anaerobic biological treatment. After anaerobic biological treatment the BOD and COD values have been reduced to 300 mg/1 and 621 mg/1 respectively. Further reduction BOD and COD values were achived in aerobic biological treatment. The scheme of process followed for the treatment and the variables that control the catalytic oxidation process, and anaerobic treatment of catalytic oxidised sample is discussed.

Three dimensional electro catalytic oxidation of aniline by boron doped mesoporous activated carbon

S. Karthikeyan,K. Viswanathan,R. Boopathy,P. Maharaja,G. Sekaran 한국공업화학회 2015 Journal of Industrial and Engineering Chemistry Vol.21 No.1

In this report, boron doped mesoporous activated carbon (B-MAC) was synthesized by directhydrothermal route. The prepared B-MAC was characterized for HR-TEM, wide-angle XRD, SEM, XPS,FTIR and N2 sorption analyses. The results suggested that the B-MAC is mesoporous in structure andamorphous in nature, with surface area of 3.036 m2 g 1. The B-MAC was chosen as a catalyst for theelectrochemical oxidation of synthetic aniline solution. For the oxidations process, graphite rod waschosen as anode; SS 316 was chosen as cathode in the electrochemical catalytic oxidation process. Theelectro chemical oxidation of aqueous aniline solution was confirmed through UV–visible spectroscopy,Florescence emission spectrum and cyclic voltammetry analyses. The results revealed that, the removalefficiency of COD and aniline by B-MAC was found to be 76–80% and 80–85%, respectively, in electrocatalytic oxidation. MAC fluidized electro catalytic oxidation system removed COD by 40–45% andaniline by 50–62%, respectively. Thus, the B-MAC catalyst was found to be viable for the electrochemicaltreatment of aniline containing waste water.

A porous activated carbon supported Pt catalyst for the oxidative degradation of poly[(naphthaleneformaldehyde)sulfonate]

Karthikeyan, S.,Jo, Wan-Kuen,Dhanalakshmi, R.,Isaacs, Mark A.,Wilson, Karen,Sekaran, G.,Lee, Adam F. Elsevier 2018 JOURNAL- TAIWAN INSTITUTE OF CHEMICAL ENGINEERS Vol.93 No.-

<P><B>Abstract</B></P> <P>Wet catalytic oxidation of sodium poly[(naphthaleneformaldehyde)sulfonate], a hazardous contaminant of wastewater streams from the textiles industry, by hydrogen peroxide under ambient conditions was explored over platinum supported on a porous activated carbon (PAC). Bulk and surface properties of the Pt/PAC catalyst were investigated by XRD, XPS, SEM, TEM, FTIR, EPR and thermogravimetric analysis. The parent PAC, derived from pyrolysis and subsequent activation of rice husks, exhibited significant micro- and mesoporosity, and a high degree of surface oxidation. Incorporation of 1.7 wt% Pt resulted in mesopore blockage, and a corresponding drop in surface area, associated with the formation of large ∼8 nm metallic nanoparticles. Poly[(naphthaleneformaldehyde)sulfonate] oxidative degradation was studied as a function of reactant concentration and solution pH, revealing first order decomposition kinetics and good activity over pH 3–9 at ambient temperature. Electron Paramagnetic Resonance (EPR)-DMPO spin trapping experiments confirm that oxidation of the organic pollutant proceeded via hydroxyl radical generation. The 1.7 wt% Pt/PAC catalyst showed excellent catalyst stability for five consecutive runs over 25 h in a fluidised bed reactor, delivering > 85% removal of 100 mg/L sulfonate with negligible Pt leaching or activity loss, and comparable performance for treatment of a real tannery effluent stream with a COD equivalent of 1860 mg/L.</P> <P><B>Highlights</B></P> <P> <UL> <LI> A facile route to Pt functionalized biogenically sourced porous activated carbon. </LI> <LI> First heterogeneous catalyst for poly[(naphthaleneformaldehyde)sulfonate] oxidation. </LI> <LI> Excellent activity and stability over a broad concentration and pH range. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

NiO/nanoporous carbon heterogeneous Fenton catalyst for aqueous microcystine-LR decomposition

Jo, Wan-Kuen,Karthikeyan, S.,Isaacs, Mark A.,Lee, Adam F.,Wilson, Karen,Shin, Seung-Ho,Lee, Jun-ho,Kim, Mo-Keun,Park, Byung-Sik,Sekaran, G. Elsevier 2017 JOURNAL- TAIWAN INSTITUTE OF CHEMICAL ENGINEERS Vol.74 No.-

<P><B>Abstract</B></P> <P>The efficacy of NiO nanoparticles dispersed on a nanoporous carbon matrix (NiO/NPC) for microcystine-LR degradation in aqueous media is reported. The NiO/NPC catalyst was characterized by porosimetry, scanning electron microscopy, elemental analysis, powder X-ray diffraction, and X-ray photoelectron spectroscopy, and applied to the oxidative degradation of microcystine-LR contaminated water in the presence of hydrogen peroxide as a function of pH under ambient conditions. Optimal MC-LR removal efficiency was 86% at neutral pH catalyzed by this heterogeneous Fenton-like (NiO/NPC with H<SUB>2</SUB>O<SUB>2</SUB>) process, which has the added benefit of avoiding secondary metal pollution during microcystine-LR degradation. NiO/NPC represents an earth abundant catalyst for generating hydroxyl radicals to facilitate environmental depollution of organic pollutants from wastewater.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Synthesis, characterization of nickel on nanoporous activated carbon. </LI> <LI> Heterogeneous Fenton-like oxidation system for removal of microcystin-LR. </LI> <LI> Hydroxyl radical to destruction of microcystin-LR. </LI> <LI> MC-LR removal at ambient condition, neutral pH. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P> Mechanistic view of mineralization of MC-LR by NiO/NPC.</P> <P>[DISPLAY OMISSION]</P>