Migration of sulfur in in-situ gasification chemical looping combustion of Beisu coal with iron-and copper-based oxygen carriers

Chemical looping combustion(CLC)is an energy conversion technology with high efficiency and inherent separation of CO_(2).The existence of sulfur in coal may affect the CO_(2) purity and the performance of oxygen carrier due to the interactions between sulfur contaminants and oxygen carrier.The migration of sulfur in Beisu coal during the in-situ gasification chemical looping combustion(i G-CLC)process using two oxygen carriers(iron ore and Cu O/Si O_(2))was investigated respectively.The thermodynamic analysis results showed the formation of metal sulfides was thermodynamically favored at low temperatures and low oxygen excess coefficients,while they were obviously inhibited and the production of SO_(2) was significantly promoted with an increase in temperature and oxygen excess coefficient.Moreover,part of sulfur was captured and fixed in the forms of alkali/alkaline earth metal sulfate due to the high amount of alkali/alkaline earth metal oxides in the coal ash or/and oxygen carrier.The experimental results showed that the sulfur in coal mainly released in the form of SO_(2),and the sulfur conversion efficiency(XS)in the reduction stage were 51.04%and 48.24%when using iron ore and Cu O/Si O_(2) respectively.The existence of metal sulfides was observed in the reduced oxygen carriers.The values of XSin the reoxidation process reached 3.80%and 7.64%when using iron ore and Cu O/Si O_(2) respectively.The residue and accumulation of sulfur were also found on the surfaces of two oxygen carriers.

Effects of iron and humic acid on competition between Microcystis aeruginosa and Scenedesmus obliquus revealed by HPLC analysis of pigments

Iron is a vital micronutrient for growth of bloom-forming Microcystis aeruginosa and competition with other algae,and its availability is affected by humic acid.The effect of iron and humic acid on growth and competition between M.aeruginosa and Scenedesmus obliquus was assessed.The results showed the growth of M.aeruginosa and S.obliquus in mono-cultures was inhibited by humic acid at low iron concentrations(0.01 mg/L);the maximum inhibition ratios were 67.84%and 38.31%,respectively.The inhibition of humic acid on the two species was significantly alleviated when iron concentrations were 1.00 mg/L,with the maximum inhibition rate reduced to 5.82%for M.aeruginosa and to 23.06%for S.obliquus.S.obliquus was the dominant species in mixed cultures,and the mutual inhibition between M.aeruginosa and S.obliquus at low iron concentration was greater than that at high iron concentration.The inhibition of S.obliquus on M.aeruginosa was reduced at low iron concentrations;it increased at high iron concentrations,as concentrations of humic acid rose.

Purification of specularite by centrifugation instead of flotation to produce iron oxide red pigment

This study used specularite, a high-gradient magnetic separation concentrate, as a raw material in reverse flotation.An iron concentrate with a grade of 65.1 wt% and a recovery rate of 75.31% were obtained.A centrifugal concentrator served as the deep purification equipment for the preparation of iron oxide red pigments, and its optimal rotating drum speed, feed concentration, and other conditions were determined.Under optimal conditions, a high-purity iron oxide concentrate with a grade of 69.38 wt% and a recovery rate of 80.89% were obtained and used as a raw material for preparing iron oxide red pigment.Calcining with sulfuric acid produced iron red pigments with different hues.Simultaneously, middlings with a grade of 60.20 wt% and a recovery rate of 17.51% were obtained and could be used in blast furnace ironmaking.High-value utilization of specularite beneficiation products was thus achieved.

The Analysis of Silicon-iron-peach Occlusion Pigment 510B in Mossbauer Spectra

Silicon iron peach pigment 510B in Mossbauer spectra was analyed,the results show that there are mainly two kinds of iron phase mineral existing in 510B pigment,α FeO(OH) and γ FeO(OH).The Mossbauer spectra of 510B sample after being calcined in 1200℃ was also analyzed.

Hydrometallurgical Processing of Brazilian Iron Ore Tailings for the Synthesis of Pigments

The aim of this study was to investigate the synthesis of iron oxide pigments from IOT. The sample of IOT was obtained through mining activity of the Quadrilátero Ferrífero in the state of Minas Gerais, Brazil. The procedure was carried out by hot acid leaching with hydrochloric acid (HCl) which allowed the recovery of about 95% of the iron in a liquor. The iron-based pigments—red (IBP_R), black (IBP_B), and yellow (IBP_Y)—were synthetised from the liquor by selective precipitation, crystallisation, and thermal procedures. The pigments were characterised by particle size distribution, mineral and chemical compositions, as well as colourimetric properties. The process of synthesis was successful and the procedure was shown to maximise the utilisation of mineral resources and minimise the environmental, social, and economic impacts associated with IOT disposal.

2024年一季度中国涂料、颜料行业经济运行简析

简析了2024年第一季度我国涂料行业生产、经营和涂料、无机颜料行业进出口简况,并对丙烯酸乳液、环氧树脂等重点成膜物质市场进行了综述和预测。对2024年一季度涂料行业双指数进行了分析,并对二季度市场进行了预测。

硫酸亚铁废液的综合回收利用

在工业生产中每年都会产生大量的硫酸亚铁废液,其中钢铁深加工过程的产出量最大。硫酸亚铁废液中含有硫酸,pH值较低,且含有铁、钴、镍、铝、铬等金属离子,直接排放不仅浪费其中的金属资源,还会对土壤和水体造成严重污染。综合回收硫酸亚铁废液对企业具有巨大的经济效益,对社会具有一定的环境效益。目前主要的处理方法有中和处理法、化学沉淀法、结晶析出法、溶剂萃取法、微生物法等。针对不同生产过程产生的硫酸亚铁废液应采用相应的处理办法。由于中和处理法产生大量金属污泥、结晶析出法的产品市场需求低、溶剂萃取法处理能力低、微生物法处理周期长,化学沉淀法是目前主要采用的回收方法。化学沉淀法操作简单、无需高性能设备,但试验影响因素多,产品性质波动大。硫酸亚铁废液回收产品主要被应用于颜料行业、水处理行业、磁性材料行业等。多数产品仅利用了废液的铁元素,而硫酸和硫元素并未得到回收利用,如何对废液进行综合回收是一个研究重点。由于硫酸亚铁废液中杂质元素含量较多,对其进行提纯具有很大的难度,所需生产成本也较高,因此如何直接利用废液也是未来研究的主要方向。

不同颜料对超高性能混凝土性能的影响研究

超高性能混凝土(UHPC)因其高强、高韧、高耐久等独特性能优势在彩色装饰混凝土领域的应用日益增长,然而作为一种新型特种混凝土材料,颜料对彩色UHPC性能的影响规律还有待进一步研究。本文系统研究了3种氧化铁颜料及其掺量变化对UHPC工作性能、力学性能的影响,结果表明:不同颜料均会一定程度降低UHPC的工作性能;随着氧化铁红、氧化铁黄颜料的掺加,UHPC的抗折、抗压强度呈先增加后减小的趋势,但掺加氧化铁黄不利于UHPC抗拉强度的发展,在相同掺量下氧化铁红对UHPC的抗折、抗压及抗拉强度改善效果更加显著;UHPC的抗折、抗压和抗拉强度随着氧化铁绿掺量的提升持续下降;综合分析UHPC的工作性能及力学性能,3种氧化铁颜料的掺量为0%~1%时较为适宜。

Effects of Iron on Growth and Intracellular Chemical Contents of Microcystis aeruginosa

Objective To investigate the effect of iron on the growth, physiology and photosynthesis of cyanobacteria. Methods A gradient of iron concentrations was employed to investigate the growth, photo-pigments （chlorophyll A and phycocyanin）, and cell chemical contents （C, N, P） of Microcystis aeruginosa in response to different iron additions. Results The specific growth rate during the exponential growth phase, as well as the cell chlorophyll A and the phycocyanin content, was limited by iron below 12.3μmol Fe.L^-1. The growth was inhibited when the iron concentration was at 24.6 μmol Fe.L^-1. The cell chlorophyll A and the phycocyanin content were saturated when the iron concentration was above 12.3μmol Fe.L^-1 and declined slightly at 24.6 μmol Fe.L^-1. At a low iron concentration （about 6.15 μmol Fe-L^-1 and less）, the cell nitrogen and carbohydrate content were iron limited, and the variation of the cell phosphorus content was similar to that of the nitrogen and carbohydrate, with a transition point of 12.3 μmol Fe.L^-1. Conclusion The variation ofcynobacteria growth is synchronous with that of the photo-pigments or the cell chemical content, and there exist relationships among photosynthesis, growth and internal chemical content, which could be useful for the growth estimation from the cell characteristics.

ASPECTS OF IRON NUTRITION IN MACROALGAE ULVA PERTUSA (CHLOROPHYTA) UNDER IRON STRESS

Fe, Chlorophyll (Chl) and total nitrogen (TN) content in tissues were measured in Fe-deficient cultures of Ulva. pertusa over a period of 60 days. Photosynthetic carbon fixation rates were studied at the start of and 30 days after Fe-deficiency culture, when the effects of Fe-deficiency on the ultrastructure were also analyzed. The iron content in tissue decreased exponentially during Fe-deficiency (from 726.7 to 31.6 μg/gdw) and simultaneously Chl and TN content declined to 4.35% and 59.9% of their original levels respectively. Maximum carbon fixation rate (50-250 μmol/m 2 s) under Fe-deficiency decreased significantly compared with the control (p<0.01) and was 13.6 to 0.365 μg C /cm 2 h. Photosynthesis in Fe-deficient cells became light-saturated at lower irradiance than that in control. Ultrastructural observations of Fe-deficient cells showed reductions in chloroplast number, some degeneration of lamellar organization, an increase in vacuolar area, a decrease in mitochondrial matrix density, and variation in accumulation body number and morphology. During Fe-deficiency, the algae growth rate continued to decline and after 6 weeks of iron deficiency, no further growth was detectable. These suggested that the lower growth rate of Ulva. pertusa under Fe-deficiency could be due mainly to nitrogen utilization and inhibition of photosynthesis.

Preparation of Novel Scorzalite Imitated Phosphate Pigments

Novel phosphate pigments imitated with Scorzalite,FeAl2(PO4)2(OH)2,were prepared from iron and aluminum nitrate solutions,ascorbic acid,and phosphoric acid with pH adjustments(pH 5,7,9).The obtained precipitates were heated at 300,500,and 700°C for 1 h.The precipitates and their thermal products were estimated with X-ray diffraction(XRD),Infrared(IR)spectra,ultraviolet-visible(UV-Vis)reflectance spectra,and L*a*b*color space.The precipitated sample was not clearly colored,but it turned orange to red when heated.Samples prepared at low pH showed higher whiteness than samples prepared at high pH.The theoretical amount of ascorbic acid was sufficient to completely reduce iron during the adjustment.This study showed the possibility of novel inorganic phosphate red pigment.

氧化铁掺量对彩色混凝土性能的影响研究

传统混凝土色彩单一,难以满足建筑领域个性化的设计需求,为了改变混凝土单一色彩的现状,使之能融合城市发展,适应工程需要,研究通过在混凝土中掺入氧化铁颜料,配制彩色混凝土,并确定影响彩色混凝土的因素。结果表明:颜料掺量>5%时,掺加氧化铁蓝和氧化铁绿的混凝土颜色达到均匀,随着颜料掺量的提高,混凝土颜色的加深程度逐渐减小;当氧化铁颜料掺量超过5%时,彩色混凝土的坍落度损失逐渐增大;当氧化铁颜料掺量在1%~10%时,对彩色混凝土的强度影响不大,但对彩色混凝土的坍落度损失有一定影响;氧化铁颜料的投料顺序和坍落度大小对彩色混凝土的表观颜色影响不明显;彩色混凝土的搅拌时间应适当延长至60s以上,使颜色达到均匀;原材料的变化对混凝土的颜色有一定的影响;不同氧化铁种类配制的彩色混凝土,其褪色时间和耐久性能各不相同。

外源铁对高有机负荷下泰来草光合作用及抗氧化酶活性的影响

海草床是近岸重要的“蓝碳”生态系统,有机负荷升高导致的硫化物胁迫是海草床衰退的重要诱因;外源铁(Fe)的添加可有效改善高有机负荷沉积物中海草的生存状态。本研究在日光温室内,通过向两种不同类型(钙质和硅质)沉积物中添加淀粉(5 g/kg)模拟海草床高有机负荷,同时添加不同量的Fe(II)(0.00、0.05、0.15、0.50 g/kg),探究了泰来草(Thalassia hemprichii)叶片光合色素(Chl a、Chl b、Cx)含量、叶绿素荧光参数(F_(m)、F_(v)/F_(m)、F_(v)/F_(0)、Φ_(PSII)、ETR)及抗氧化酶(POD、SOD、CAT)活性对Fe添加的响应特点。结果表明,培养过程(30 d)中,两种类型的沉积物中外源Fe添加均能有效提升泰来草叶片光合色素含量、叶绿素荧光参数水平和抗氧化酶活性,且当Fe(Ⅱ)添加量为0.50 g/kg时效果最优。Fe添加量对间隙水Fe 2+浓度、S 2-浓度、泰来草叶片光合色素含量、叶绿素荧光参数及抗氧化酶活性均存在极显著(P<0.01)影响,底质类型对Fe 2+浓度、抗氧化酶活性存在极显著(P<0.01)影响,底质类型与Fe添加量的交互作用对光合色素含量和抗氧化酶活性存在显著(P<0.05)或极显著(P<0.01)影响。总体而言,Fe添加对泰来草光合作用和抗氧化酶活性的影响高于底质类型。本研究表明外源Fe能够有效改善钙质、硅质沉积物中泰来草生理生态指标。

铸铁排水管道内壁防腐蚀涂料的制备与性能研究

介绍了铸铁排水管的腐蚀工况,分析腐蚀机理及对涂层的性能要求。通过对树脂体系搭配、颜填料的筛选确定配方结构,最终对比不同颜基比下的涂层性能,得到最优体系及配比,研制出铸铁管专用无溶剂重防腐涂料。

微乳液法制备包裹型锆铁红陶瓷颜料

利用辛基苯基聚氧乙烯醚(tritonX–100)/正己醇/环己烷所形成的水/油型微乳液首先获得了Fe–ZrSiO_4红色陶瓷颜料的前驱体,经煅烧后合成了包裹型的锆铁红陶瓷颜料。通过热重–差热分析、X射线衍射、透射电子显微镜、能谱分析及色度测试等对颜料的形成过程、微观结构及性能进行了表征和分析。结果表明微乳液法所制备锆铁红颜料前驱体为无定形粉末,且残留有一定量的表面活性剂等有机物;该前驱体在600℃以下会发生约45%的质量损失,600℃以上质量几乎不再发生改变。无矿化剂作用下,锆铁红陶瓷颜料的开始形成温度约为1100℃;前驱体在1200℃煅烧并保温1h可获得包裹型锆铁红陶瓷颜料,该颜料红度值较高(a=28.95),且具有较高的包裹率。

铁和镍对光合细菌生长和产氢的影响

基于金属元素在生物体功能发挥中的作用以及它们参与光合细菌光合放氢的重要性 ,着重进行了铁和镍对沼泽红假单胞菌 (Rhodopseudomonaspalustris)Z菌株和一株红杆菌(Rhodobactersp.)细胞生长、光合放氢和光合色素合成影响的研究。结果表明 ,高浓度Fe3+可显著提高两菌株光放氢能力和生物合成能力 ,最适浓度的Fe3+可使其产氢能力分别达对照组的 1 32倍和 2 8倍 ,产氢得率分别为 360 6mL g和 385 9mL g,生物量分别为对照组的1 42倍和 1 5 4倍。 9μmol LNi2 +的添加可使两菌株产氢能力分别达对照组的 1 48倍和 1 96倍 ,产氢得率分别为 42 9 7mL g和 45 6 3mL g。而当Ni2 +浓度为 1 2 μmol L时 ,两菌株的产氢活性受到不同程度的抑制 ,产氢得率分别降低 46 7%和 1 9 4%。在铁浓度相同时 ,添加 6μmol LNi2 +能明显促进两菌株的生长。而当Ni2 +浓度大于 6μmol L时 ,细胞生长受到抑制。Fe3+和Ni2 +对Rhodobactersp .菌株类胡萝卜色素有显著影响。研究结果显示 ,42 6nm色素峰随铁浓度的增加和镍的添加而消失 ,同时 。

透明氧化铁黄颜料的制备

以硫酸亚铁为原料，氢氧化钠为沉淀剂，加入分散剂和表面活性剂、采用阳离子调节剂和晶粒控制剂复配的复合剂，采用空气氧化法制得性能优良的透明氧化铁黄颜料。探讨反应物浓度、沉淀剂用量、反应温度、通气量、搅拌转速、添加剂等对产品性能的影响。

用工业废铁粉制取铁红颜料的实验研究

介绍了用工业废铁粉制取氧化铁红的化学反应机理及生产工艺过程 .采用正交实验的方法研究了原料配比、煅烧时间、煅烧温度、添加剂等因素对产品质量的影响 .实验结果表明 ,在70 0～ 80 0℃时 ,加适量添加剂煅烧 40分钟左右可以得到质量较好的氧化铁红产品 .