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Effect of cao on retention of S, Cl, Br, As, Mn, V, Cr, Ni, Cu, Zn,W and Pb in bottom ashes from fluidized-bed coal combustion power station

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Journal of Environmental Sciences 2014年第7期26卷 1429-1436页

作者： Lucie Bartonova Zdenek Klika Energy Units for Utilization of Non-Traditional Energy Sources Centre V?B-Technical University of Ostrava 708 33 Ostrava-Poruba Czech Republic Regional Material and Technology Research Centre VSB-Technical University of Ostrava 708 33 Ostrava-Poruba Czech Republic

This work was conducted to evaluate whether Ca-bearing additives used during coal combustion can also help with the retention of some other elements. This work was focused on the evaluation of bottom ashes collected during four full-scale combustion tests at an operating thermal fluidized-bed power station. Bottom ashes were preferred to fly ashes for the study to avoid interference from condensation processes usually occurring in the post-combustion zone. This work focused on the behaviors of S, Cl, Br, As, Mn, V, Cr, Ni, Cu,Zn, W, and Pb. Strong positive correlations with cao content in bottom ashes were observed（for all four combustion tests） for S, As, Cl and Br（R = 0.917-0.999）. Strong inverse proportionality was calculated between the contents of Pb, Zn, Ni, Cr and Mn and cao, so these elements showed association to materials other than Ca-bearing compounds（e.g., to aluminosilicates, organic matter, etc.）. Somewhat unclear behaviors were observed for W, Cu, and V. Their correlation coefficients were evaluated as statistically ＂not significant＂, i.e., these elements were not thought to be significantly associated with cao. It was also discovered that major enrichment of cao in the finest bottom ash fractions could be advantageously used for simple separation of elements strongly associated with these fractions, mainly S and As, but also Cl or Br. Removal of5% of the finest ash particles brings about a decrease in As concentration down to 77%-80% of its original bulk ash content, which can be conveniently used e.g., when high As content complicates further ash utilization.

关键词： Coal combustion Arsenic Chlorine Bromine cao Retention Fluidized-bed Trace elements

Preparation and Characterization of cao/ZnO Core-shell Structured Nanoparticles

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Chemical Research in Chinese Universities 2020年第5期36卷 970-975页

作者： WANG Lili LIU Yanan PENG Xiaoxing SUN Yuanqing LIU Xiaohua LIU Huimin LIN Quan SUN Hongchen YANG Bai LI Xiangwei School of Stomatology Jilin UniversityChangchun 130021P.R.China Hospital Attached to Changchun University of Chinese Medicine Changchun 130041P.R.China State Key Laboratory of Supramol ecular Structure and Materials Jilin UniversityChangchun 130012P.R.China Department of Biomedical Sciences Texas A&M UniversityCollege of DentistryDallasTX 75246USA

Residual bacteria and microleakage in a complicated root canal can often result in reinfection of the periapical *** promote the antibacterial and sealing eftects of a root canal filling,core-shell structured cao/ZnO nanospheres were synthesized using a precipitation method based on a traditional root canal sealer,zinc oxide-eugenol(ZOE).The obtained cao/ZnO particles had a size of 80—90 nm and a core-shell *** film thickness,flow rate,pH,and calcium ion release of the core-shell structured cao/ZnO nanospheres-eugenol paste were *** pH and calcium ion release results showed a slight increase in the prepared nanospheres,with a flow rate of 24.22 mm and a formed film thickness of 30 pm,which are basically consistent with ISO 6876:2001 standards(regarding dental root canal sealing materials).Cytotoxicity tests showed that the cytocompatibility of the cao/ZnO nanospheres-eugenol paste was much higher than that of the ZOE or iRoot SP groups(Pcao/ZnO nano spheres-eugenol paste had significantly better effects than the ZOE and iRoot SP sealers(Pcao/ZnO nano sphere paste displayed excellent sealing and antibacterial properties,and it has promising application potential in endodontics.

关键词： cao ZnO Antibacterial activity Core-shell stnictured naiiosphere Microleakage

Behavior of cao and Calcium in pure Magnesium

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Rare Metals 2006年第Z2期25卷 150-154页

作者： HA Seong-Ho LEE Jin-Kyu JO Hyung-Ho JUNG Seung-Boo KIM Shae K. Department of Advanced Material Engineering Sungkyunkwan University 300 Chunchun-dong Jangan-gu Suwon Gyunggi-do 440-746 KoreaAdvanced Material Division Korea Institute of Industrial Technology 7-47 Songdo-dong Yeonsu-gu Incheon 406-840 Korea Advanced Material Division Korea Institute of Industrial Technology 7-47 Songdo-dong Yeonsu-gu Incheon 406-840 Korea Department of Advanced Material Engineering Sungkyunkwan University 300 Chunchun-dong Jangan-gu Suwon Gyunggi-do 440-746 Korea

Mg alloys exhibit a number of good properties such as low density, good castability and high specific strength. However, molten Mg and Mg alloys are ignited without the melt protective gases during melting and casting process due to their high reactivity. The purpose of this study is to investigate effects of Ca and cao on pure Mg through microstructure observation, ignition test and phase analysis. With increasing Ca and cao contents, the ignition resistance of Ca or cao added pure Mg is increased and the grains are refined. As results of XRD and EDS, cao is reduced to Ca in cao added pure Mg. Mg2Ca phase is formed even in 0.1 wt.%cao added pure Mg by reduction mechanism, while Mg2Ca phase is formed over 1.35 wt.% Ca added pure Mg.

关键词： Mg cao ignition resistance Mg2Ca phase

Synthesis of porous cao microsphere and its application in catalyzing transesterification reaction for biodiesel

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中国有色金属学会会刊：英文版 2009年第S3期19卷 674-677页

作者：白海鑫沈晓真刘小花刘圣勇 College of Sciences Henan Agricultural University College of Mechanical and ElectricalEngineering Henan Agricultural University College of Mechanical and Electrical Engineering Henan AgriculturalUniversity College of Mechanical and Electrical Engineering Henan Agricultural University

It is hoped to develop a simple and low cost route for preparing the cao with a novel morphology which can present high catalytic activity in catalyzing transesterification reaction for biodiesel. The porous cao microsphere was synthesized by calcining spherical CaCO3 precursor which was prepared easily by mixing CaCl2 with Na2CO3. The as-prepared cao microsphere was characterized by scanning electronic microscopy(SEM), powder X-ray diffractometry(XRD) and N2 adsorption experiment. The results reveal that the synthesized cao is regular microsphere with many pores in its exterior and interior. The cao microsphere is applied in catalyzing the transesterification reaction of soybean oil for biodiesel and presents excellent catalytic ability with a transesterification yield of 98.72%. This catalyst could have potential applications in other fields in view of its well-defined morphology, simply synthetic route and low cost.

关键词： porous cao microsphere transesterification catalysis biodiesel

Influence of NaCl-CaCl_2 on Decomposing REPO_4 with cao

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Journal of Rare Earths 2007年第6期25卷 779-782页

作者：孙树臣吴志颖边雪高波吴文远涂赣峰 School of Materials & Metallurgy Northeastern University

The influence of NaCl-CaCl2 on thermal decomposition of REPO4（RE： Ce, La, Nd, Th） with cao was studied. The heat decomposing process of REPO4 was tested with TG-DTA experiments. The results showed that the decomposition temperature of REPO4 with cao was reduced because of adding NaCl-CaCl2 mixture （NaCl：CaCl2 = 1：1 ）. The influence of the addition of NaCl-CaCl2, roasting temperature and roasting time on decomposition ratio of REPO4 with cao was studied. The results showed that the decomposition ratio of REPO4with cao was 79% when the addition percentage of NaCl-CaCl2 was 10%, the roasting temperature was 750℃, and the roasting time was 1 h.

关键词： NaCl-CaCl2 cao REPO4 decomposition ratio rare earths

Effect of cao composition on oxidation and burning behaviors of AM50 Mg alloy

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Transactions of Nonferrous Metals Society of China 2011年第A1期21卷 23-27页

作者： Jin-Kyu LEE Shae K.KIM Advanced Material Division Korea Institute of Industrial Technology 7-47 Songdo-Dong Yeonsu-Gu Incheon 406-840 Korea

Oxidation and burning behaviors were studied for cao added AM50 Mg composites which were manufactured by conventional melting and casting processes without SF6 protective gas. cao added AM50 Mg composites show the stable oxidation resistance, while AMS0 Mg alloys show the poor oxidation resistance. The effects of cao addition on the burning resistance under ambient, nitrogen and dry air atmospheres were examined for cao added AM50 Mg composites. With increasing cao addition, the burning temperature increases under ambient, nitrogen and dry air atmospheres. The burning temperatures of small test specimen under all conditions greatly increase even by 0.3% cao （mass fraction） addition into AM50 Mg alloys.

关键词： Mg alloy cao oxidation behavior burning behavior

Effect of cao addition on ignition behavior in molten AZ31 and AZ91D Magnesium alloys

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Rare Metals 2006年第Z2期25卷 155-159页

作者： LEE Jin-Kyu JO Hyung-Ho KIM Shae K. Department of Advanced Material Engineering Sungkyunkwan University 300 Chunchun-dong Jangan-gu Suwon Gyunggi-do 440-746 KoreaAdvanced Material Center Korea Institute of Industrial Technology 7-47 Songdo-dong Yeonsu-gu Incheon 406-840 Korea dvanced Material Center Korea Institute of Industrial Technology 7-47 Songdo-dong Yeonsu-gu Incheon 406-840 Korea

Mg alloys have been widely used in automobile and electronic industries because of high specific strength, good castability, etc. However, molten Mg alloys will burn rapidly in air if not protected. To solve this problem, the molten metal should be protected from oxidation by blanketing the surface with flux or protective gases. SF6 gas is widely used for Mg alloys as a cover gas and has proved to be a successful inhibitor. However, the use of SF6 gas is limited because of its high cost and its significant impact on non-global warming potential. Therefore, SF6 gas is being replaced by alternative protection gases. Recent studies show that there has been another attempt by adding cao into Mg alloys. The aim of this study is to evaluate the effect of cao on the minimum amount of protective gas, which is necessary not to make ignition in the molten AZ31 and AZ91 Mg alloys.

关键词： AZ91 AZ31 cao clean production ignition resistance

Development of cao From Natural Calcite as a Heterogeneous Base Catalyst in the Formation of Biodiesel:Review

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Journal of Renewable Materials 2019年第10期7卷 915-939页

作者： Nuni Widiarti Yatim Lailun Ni’mah Hasliza Bahruji Didik Prasetyoko Department of Chemistry Faculty of SciencesInstitute Technology Sepuluh Nopember Surabaya 60111Indonesia Jl.Arief Rahman HakimSukoliloSurabaya 60111Indonesia Center of Advanced Materials and Energy Science Universiti Brunei DarussalamNegara Brunei Darussalam.

Biodiesel is a fossil fuel that is in demand to be developed because it is bio-renewable,biodegradable and environmentally *** produced from the transesterification reaction of vege *** using a base *** is the most developed catalyst for the reaction of transesterification of oil into biodiesel because it is cheap,the process is easy and has a high level of *** is a cheap catalyst because it is easily obtained from natural *** use of cao catalysts in the reaction formation of biodiesel continues to develop through modification with various porous materials and different oxide *** this paper,we discuss the development of cao,the modification of cao with a porous material and metal oxide,the mechanism of reaction of cao and the kinetics of reactions that occur in the reaction transesterification of oil to biodiesel.

关键词： Biodiesel cao modification transesterification

SGCS-made ultrafine cao/Al_2O_3 sorbent for cyclic CO_2 capture

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Chinese Chemical Letters 2011年第5期22卷 615-618页

作者： Cong Luo Ying Zheng Ning Ding Qi Long Wu Chu Guang Zheng State Key Laboratory of Coal Combustion Huazhong University of Science and Technology Wuhan 430074 China

Multi-cyclic cao carbonation/calcination is an attractive method for CO_2 capture during coal ***,the capture capacity of cao sharply decreases with increasing carbonation/calcination *** order to improve the stability of CO_2 capture capacity of cao during carbonation/calcination cycles,synthetic cao/Al_2O_3 sorbents were synthesized by two methods：wet chemistry and sol-gel-combustion-synthesis（SGCS） to make a further *** results indicate that the SGCS-made cao/ Al_2O_3 = 80：20 wt%sorbent provides a competitive performance of a capture capacity of 0.43 g-CO_2/g-sorbent after 20 cycles.

关键词： CO_2 capture cao Carbonation/calcination cycles SGCS