Experimental Design Technique on Removal of Hydrogen Sulfide using CaO-eggshells Dispersed onto Palm Kernel Shell Activated Carbon：Experiment,Optimization,Equilibrium and Kinetic Studies

This study presents the use of chicken eggshells waste utilizing palm kernel shell based activated carbon（PKSAC） through the modification of their surface to enhance the adsorption capacity of H2S. Response surface methodology technique was used to optimize the process conditions and they were found to be： 500 mg/L for H2S initial concentration, 540 min for contact time and 1 g for adsorbent mass. The impacts of three arrangement factors（calcination temperature of impregnated activated carbon（IAC）, the calcium solution concentration and contact time of calcination） on the H2S removal efficiency and impregnated AC yield were investigated. Both responses IAC yield（IACY, %） and removal efficiency（RE, %） were maximized to optimize the IAC preparation conditions. The optimum preparation conditions for IACY and RE were found as follows： calcination temperature of IAC of 880 ℃, calcium solution concentration of 49.3% and calcination contact time of 57.6 min, which resulted in 35.8% of IACY and 98.2% RE. In addition, the equilibrium and kinetics of the process were investigated. The adsorbent was characterized using TGA, XRD, FTIR, SEM/EDX, and BET. The maximum monolayer adsorption capacity was found to be 543.47 mg/g. The results recommended that the composite of PKSAC and Ca O could be a useful material for H2S containing wastewater treatment.

Oil-soluble Ni-Mo sulfide nanoparticles and their hydrogenation catalytic properties

Oil-soluble bimetallic Ni-Mo sulfide nanoparticles（NiMoS） with narrow size distribution were successfully synthesized through a composite-surfactants-assisted-solvothermal process.The surface functionality and lipophilicity of the Ni-Mo sulfides were shown by transmission electronic microscopy,Fourier transform infrared and ultraviolet spectroscopy.The as-prepared Ni-Mo sulfides supported on activated carbon（NiMoS/AC） exhibited enhanced catalytic activity towards naphthalene hydrogenation instead of cracking.For comparison,CoMoS/AC and MoS2/AC catalysts were also prepared through similar procedures,and it was found that their catalytic performance decreased in the order of NiMoS/AC〉CoMoS/AC〉MoS2/AC.Furthermore,the activity of the bimetallic NiMoS nanocatalyst can be effectively tuned via variation of the atomic ratio of Ni/（Ni＋Mo）.

Adsorption-oxidation of hydrogen sulfide on Fe/walnut-shell activated carbon surface modified by NH_3-plasma

Walnut-shell activated carbon（WSAC） supported ferric oxide was modified by non-thermal plasma（NTP）, and the removal efficiency for hydrogen sulfide over Fe/WSAC modified by dielectric barrier discharge（DBD） was significantly promoted. The sample modified for10 min and 6.8 k V output（30 V input voltage） maintained 100% H2 S conversion over a long reaction time of 390 min. The surface properties of adsorbents modified by NTP under different conditions were evaluated by the methods of X-ray photoelectron spectroscopy（XPS）, Brunauer–Emmett–Teller（BET） analysis and in-situ Fourier transform infrared spectroscopy（FTIR）, to help understand the effect of the NTP treatment. NTP treatment enhanced the adsorption capacity of Fe/WSAC, which could due to the formation of micro-pores with sizes of0.4, 0.5 and 0.75 nm. XPS revealed that chemisorbed oxygen changed into lattice oxygen after NTP treatment, and lattice oxygen is beneficial for H2 S oxidation. From the in-situ FTIR result,transformation of the reaction path on Fe/WSAC was observed after NTP modification. The research results indicate that NTP is an effective method to improve the surface properties of the Fe/WSAC catalyst for H2 S adsorption-oxidation.

Simulation Experiments on the Reaction of CH_4-CaSO_4 and Its Carbon Kinetic Isotope Fractionation

Thermochemical sulfate reduction (TSR) in geological deposits can account for the accumulation of H2S in deep sour gas reservoirs. In this paper, thermal simulation experiments on the reaction of CH4-CaSO4 were carried out using an autoclave at high temperatures and high pressures. The products were characterized with analytical methods including carbon isotope analysis. It is found that the reaction can proceed to produce H2S, H2O and CaCO3 as the main products. Based on the experimental results, the carbon kinetic isotope fractionation was investigated, and the value of Ki (kinetic isotope effect) was calculated. The results obtained in this paper can provide useful information to explain the occurrence of H2S in deep carbonate gas reservoirs.

Confined synthesis of MoS_(2) with rich co-doped edges for enhanced hydrogen evolution performance

Activating MoS_(2) with atomic metal doping is promising to harvest desirable Pt-matched hydrogen evolution reaction(HER)catalytic performance.Herein,we developed an efficient method to access edgerich lattice-distorted MoS_(2) for highly efficient HER via in-situ sulphuration of atomic Co/Mo species that were well-dispersed in a formamide-derived N-doped carbonaceous(f-NC)substrate.Apart from others,pre-embedding Co/Mo species in f-NC controls the release of metal sources upon annealing in S vapor,grafting the as-made MoS_(2) with merits of short-range crystallinity,distorted lattices,rich defects,and more edges exposed.The content of atomic Co species embedded in MoS_(2) reaches up to 2.85 at.%,and its atomic dispersion has been systematically confirmed by using XRD,HRTEM,XPS,and XAS characterizations.The Co-doped MoS_(2) sample exhibits excellent HER activity,achieving overpotentials of 67 and155 m V at j=10 m A cm^(-2) in 1.0 M KOH and 0.5 M H_(2)SO_(4),respectively.Density functional theory simulations suggest that,compared with free-doping MoS_(2),the edged Co doping is responsible for the significantly improved HER activity.Our method,in addition to providing reliable Pt-matched HER catalysts,may also inspire the general synthesis of edge-rich metal-doped metal chalcogenide for a wide range of energy conversion applications.

Simultaneous recovery of carbon and sulfur resources from reduction of CO_2 with H_2S using catalysts

An approach to the simultaneous reclamation of carbon and sulfur resources from CO2 and H2S has been proposed and effectively implemented with the aid of catalysts. A brief thermodynamic study reveals the potential of direct reduction of CO2 with H2S（15：15 mol% balanced with N2） for selective production of CO and elemental sulfur. The experiments carried out in a fixed-bed flow reactor over the temperature range of 400–800 °C give evidence of the importance of the employment of catalysts. Both the conversions of the reactants and the selectivities of the target products can be substantially promoted over most catalysts studied. Nevertheless, little difference appears among their catalytic performance. The results also prove that the presence of CO2 can remarkably enhance H2S conversion and the sulfur yield in comparison with H2S direct decomposition. A longtime reaction test on Mg O catalyst manifests its superior durability at high temperature（700 °C） and huge gas hourly space velocity（100,000 h-1）. Free radicals initiated by catalysts are supposed to dominate the reactions between CO2 and H2S.

Wavelength-sensitive photocatalytic H2 evolution from H2S splitting over g-C3N4 with S,N-codoped carbon dots as the photosensitizer

Photocatalytic splitting of hydrogen sulfide(H2S) for hydrogen evolution is a promising method to solve the energy and environmental issues.In this work,S,N-codoped carbon dots(S,N-CDs)/graphitic carbon nitride(g-C3N4) nanosheet is synthesized by hydrothermal method as an efficient photocatalyst for the decomposition of H2S.In addition to the characterization of the morphology and structure,chemical state,optical and electrochemical performances of S,N-CDs/g-C3N4,hydrogen evolution tests show that the activity of g-C3N4 is improved by introducing S,N-CDs,and the enhancement depends strongly on the wavelength of incident light.The photocatalytic hydrogen production rate of S,N-CDs/g-C3N4 composite reaches 832 μmol g-1h-1, which is 38 times to that of g-C3N4 under irradiation at 460 nm.Density functional theory calculations and electron paramagnetic resonance as well as photoluminescence technologies have altogether authenticated that the unique wavelength-dependent photosensitization of S,N-CDs on g-C3N4;meanwhile,a good match between the energy level of S,N-CDs and g-C3N4 is pivotal for the effective photocatalytic activity.Our work has unveiled the detailed mechanism of the photocatalytic activity enhancement in S,N-CDs/g-C3N4 composite and showed its potential in photocatalytic splitting of H2S for hydrogen evolution.

Isotopic Composition of Dissolved Carbonates Meromictic Soda Lake Doroninskoe(Eastern Transbaikalia,Russia)

1 Introduction Meromictic soda Lake Doroninskoe localized in the intermountain area,filled with continental sediments of the Mesozoic,in the upper basin of the river Amur.Coordinates of its location are N51°14’42"E112°14’40",

ANALYSIS OF THE REMOVAL OF H_2S WITH IMPREGNATED ACTIVATED CARBON

A general mathematical model with its governing equations in dimensionless forms has beendeveloped to describe the removal of hydrogen sulfide with impregnated activated carbon.Anapproximate relationship between the sulfur capacity and the reaction time in a single carbon pellet isobtained,and criterion to ascertain the rate controlling step of the process can then be deduced.Inthe meantime,the choice of the appropriate oxygen concentration and the principle to be followedare also described.

鄂尔多斯盆地奥陶系盐下马四段高含硫天然气地球化学特征及成因

鄂尔多斯盆地盐下天然气勘探取得重大突破,在马四段多次钻获高含硫化氢天然气,地质和地球化学特征表明其成因和来源尚不明确。通过系统采集马四段天然气、乌拉力克组页岩气和上古生界致密砂岩气样品,测定天然气的组分和碳、氢同位素组成,结合盆地中东部地质实际开展天然气成因和气源研究。结果显示,马四段天然气是以甲烷为主的干气,干燥系数平均值为0.97,乙烷平均含量为1.07%,丙烷平均含量为0.32%,其余重烃气平均含量0.38%;硫化氢平均浓度为124774×10-6,是TSR作用的产物,明显区别于上古生界致密砂岩气和乌拉力克组页岩气,研究区内由西向东硫化氢含量逐渐降低;马四段天然气中甲烷碳同位素组成介于-44.8‰~-36.4‰,平均值为-40.3‰;乙烷碳同位素组成介于-27.7‰~-19.1‰,平均值为-24.3‰;甲烷氢同位素组成介于-172‰~-140‰,平均值为-162‰;乙烷氢同位素组成介于-140‰~-112‰,平均值为-119‰;马四段天然气具有较轻的甲烷碳同位素组成和较重的甲烷氢同位素组成,指示马四段天然气具有与上古生界煤成气不同的气源。以甲烷碳、氢同位素组成及组分作为高含硫天然气的主要判识参数,识别出马四段天然气具有“自生自储”的特征,气源岩为马家沟组含膏层系发育的海相烃源岩;TSR促进了烃类向非烃的转化,重烃气向甲烷的转化,也会导致烃类碳同位素组成的变化;部分气藏乙烷碳同位素组成已经明显重于干酪根碳同位素组成,超出了热演化的影响范围,凸显TSR作用对乙烷碳同位素影响较大。基于马家沟组盐下天然气的形成演化地质背景,初步估算TSR能导致乙烷碳同位素组成变重5‰~10‰。

改性硫化钼催化剂协同低温等离子体转化H_(2)S-CO_(2)酸气制合成气的研究

以低温等离子体和催化剂耦合法将H_(2)S和CO_(2)混合酸气一步转化为合成气,既完成了两者清洁化处理,又实现了资源化利用,是一条制备合成气的新路线。本研究采用铜、锌为助剂对硫化钼催化剂改性,显著提升了其催化H_(2)S-CO_(2)制合成气反应性能。结合多种分析表征手段对比两种助剂引入后对硫化钼催化剂结构、组成、形貌、化合价态等物化特征的影响。通过控制低温等离子体放电条件,深入探究了两种助剂对低温等离子体下催化转化H_(2)S和CO_(2)酸气制合成气的反应性能影响规律和关键因素。研究发现,引入铜、锌助剂后,硫化钼活性相粒径减小且分散度高,提供了更多活性位点。同时也增强了对H_(2)S和CO_(2)分子吸附强度,从而更利于H_(2)S和CO_(2)分子的吸附活化,揭示出低温等离子体与改性硫化钼催化剂协同反应的构效关联。有关理论研究丰富拓展了低温等离子体-催化协同理论,并为改性硫化钼材料的合成提供借鉴。

活性炭吸附塔产生硫化氢的原因及解决措施研究

某矿山水处理工序采用“电石渣中和过滤—滤液活性炭吸附除油”的基本流程,针对其活性炭吸附塔产生硫化氢这一实际问题开展了分析研究,结果表明塔内SRB的生长繁殖是产生硫化氢气体的直接原因,并且得出了SRB菌种的来源为生活污水返回所致。从活性炭吸附后的水体中分离出一株SRB菌株,该菌的生长繁殖受到pH值、温度、氧气、Fe^(2+)、碳源等环境因素的影响,其中pH值和温度是影响SRB生长繁殖的重要因素。结合现场实际,对比分析了可采取的治理措施及优缺点,通过热处理治理有效抑制了细菌的生长,达到了治理效果。

外源CO和H_(2)S对NaCl胁迫下加工番茄幼苗光合及叶绿素荧光动力学的影响

[目的]研究一氧化碳(CO)和硫化氢(H_(2)S)调控作物幼苗抗盐能力的机理,为缓解盐渍土中NaCl对作物的胁迫提供理论和技术。[方法]以加工番茄品系KT-7为试验材料,采用无土栽培方法进行CO和H_(2)S叶面喷施试验。CO供体为氯化血红素溶液(hemin 15μmol/L),H_(2)S供体为硫氢化钠溶液(NaHS,50μmol/L),并因处理需要使用了H_(2)S清除剂次牛磺酸溶液(HT,100μmol/L)和血红素加氧酶抑制剂锌原卟啉溶液(ZnPPⅨ,25μmol/L)。试验共设6个处理,除对照根部浇灌营养液,叶面喷施清水外(CK_(0)),其余5个处理均根部浇灌200 mmol/L NaCl溶液,叶面分别喷施清水(CK_(1))、CO、H_(2)S、CO+HT、H_(2)S+ZnPPⅨ。幼苗长至四叶一心时,连续6天进行NaCl浇灌和叶面喷施处理,然后测定幼苗形态学指标,用Li-6800便携式光合测定仪测定光合参数,用Imaging-PAM荧光成像系统测定叶绿素荧光系数,植物效率仪测定叶绿素荧光动力学曲线(OJIP曲线)。[结果]胁迫6天后,加工番茄幼苗的各项形态学参数、净光合速率(P_(n))、实际光化学效率[Y(Ⅱ)]和光系统Ⅱ(PSⅡ)性能指标[PI_(ABS)和PI_((CSM))]显著下降,OJIP曲线产生形变,并出现K点。CO和H_(2)S处理均有效提高了加工番茄幼苗的光合色素含量、光合参数、PSⅡ的综合性能和受体侧的电子传递效率;提升了OJIP曲线中的J点、I点、P点,降低了ΔK,从而缓解了OJIP曲线的形变;CO处理的P_(n)、表观CO^(2)利用率(CUEapp)、Y(Ⅱ)和电子传递速率(ETR)分别较CK_(1)上升了75.63%、100%、60.00%和57.72%,H_(2)S处理分别上升了65.95%、100%、55.00%和52.68%,CO和H_(2)S处理均降低了非光化学淬灭和热耗散的比例,减少了PSⅡ供体侧放氧复合体(OEC)的损伤。CO+HT处理缓解NaCl胁迫的效果和CO处理相似,而H_(2)S+ZnPPⅨ处理则不能缓解NaCl胁迫,其光合色素含量、P_(n)、F_(v)/F_(m)、Y(Ⅱ)、qL、ETR、PI_(ABS)和PI_((CSM))较H_(2)S处理显著下降,热耗散比率则较H_(2)S处理显著升高。[结论]外源施用CO和H_(2)S均可通过提高光合效率,优化PSⅡ能量分配比率,保护光合电子传递链免受盐害损伤,显著提高番茄幼苗的抗盐能力。CO的作用位点可能在H_(2)S下游,具有协同H_(2)S提高加工番茄耐盐性的作用。

上行式双区复合液相柴油加氢技术的开发及应用

通过分析发现影响液相柴油加氢技术超深度脱硫效果的主要原因是油品中溶解有反应副产物硫化氢。以真实油品模拟计算了硫化氢在柴油中的溶解规律和分布情况,发现补入少量的氢气就可以实现液相工艺进行超深度加氢脱硫,由此开发了上行式双区复合液相柴油加氢技术(SLHT Dr)。中型试验结果表明,在设置的第二反应区中按照氢油体积比为30~50补入氢气,就能够克服加氢过程中硫化氢对深度脱硫反应的抑制作用,可在缓和的工艺条件下(反应温度305℃、体积空速6.0 h^(-1))获得硫质量分数小于10μg/g的精制柴油。SLHT Dr工业应用结果表明,装置能耗比同类技术降低11.9%,实现了低能耗生产,减少了生产环节的碳排放,可为未来柴油质量进一步升级及减少碳排放提供技术支撑。

硫化氢含量对加氢脱氧催化剂活性和稳定性的影响

硫化氢对维持硫化态催化剂的活性和稳定性有重要作用,通过向原料十六酸甲酯中加入不同比例的二甲基二硫醚来改变加氢反应气氛中硫化氢含量的方法来研究硫化氢对硫化态NiMo加氢脱氧催化剂活性和稳定性的影响,并采用XRD、N_(2)吸附-脱附、TG-MS、XPS和碳硫含量分析等手段对催化剂进行表征。实验结果表明,十六酸甲酯在310℃可完全脱氧,提高反应温度有利于脱羧脱羰反应路径。在0.20%(φ)硫化氢含量下催化剂能维持较高的硫化度和活性相比例,随着硫化氢含量由0.20%(φ)降至0.05%(φ),催化剂活性和稳定性降低;相比于0.20%(φ)硫化氢含量下反应后的催化剂,0.05%(φ)硫化氢含量下反应后催化剂的积碳量和积碳缩合程度更高,比表面积降幅更大,催化剂硫化度和活性相比例明显降低,硫流失现象明显;催化剂活性降低的原因可能是积碳的生成和硫的流失。

Selective and self-validating breath-level detection of hydrogen sulfide in humid air by gold nanoparticle-functionalized nanotube arrays

We demonstrate the selective detection of hydrogen sulfide at breath concentration levels under humid airflow,using a self-validating 64-channel sensor array based on semiconducting single-walled carbon nanotubes(sc-SWCNTs).The reproducible sensor fabrication process is based on a multiplexed and controlled dielectrophoretic deposition of sc-SWCNTs.The sensing area is functionalized with gold nanoparticles to address the detection at room temperature by exploiting the affinity between gold and sulfur atoms of the gas.Sensing devices functionalized with an optimized distribution of nanoparticles show a sensitivity of 0.122%/part per billion(ppb)and a calculated limit of detection(LOD)of 3 ppb.Beyond the self-validation,our sensors show increased stability and higher response levels compared to some commercially available electrochemical sensors.The cross-sensitivity to breath gases NH3 and NO is addressed demonstrating the high selectivity to H2S.Finally,mathematical models of sensors’electrical characteristics and sensing responses are developed to enhance the differentiation capabilities of the platform to be used in breath analysis applications.

南海两条混输海底管道的内腐蚀原因

南海A、B两条海底管道分别于2011年和2018年投产使用,在未达到设计使用年限就发生了腐蚀失效。根据海底管道的历史运行数据,对管道内CO_(2)和H2S、微生物、氯离子等腐蚀检测数据进行了综合分析,结合流速、含水率等,探讨了管道内腐蚀原因。结果表明:A、B海底管道在运行期间的CO_(2)含量均远超设计值,存在CO_(2)腐蚀风险,A海底管道存在CO_(2)/H_(2)S协同腐蚀;两条海底管道的输送介质中Cl^(-)含量都高,介质流速都低,存在重度微生物腐蚀,且清管方式及灭菌剂的选择不合适,最终导致A、B海底管道均未达到使用寿命即发生腐蚀失效。

元素分析仪测量煤样中碳、氢、氮含量的方法研究

元素分析仪是目前测定煤样中碳、氢、氮含量普遍采用的方法。针对煤中卤化物及硫化物易干扰碳、氢测定和对仪器管路造成腐蚀的问题,实验用氧化钙为吸收剂、五氧化二钒为催化剂与样品用锡囊包裹的方式,在样品燃烧阶段,有效解决卤素及硫化物对碳、氢测量的影响,同时提高了炉试剂使用寿命。实验结果表明,0.02 g氧化钙为吸收剂、0.03 g五氧化二钒催化剂,能有效解决煤质样品中总量约11%的氟、氯和硫对碳、氢测定的干扰;采用用锡囊代替锡箔包裹样品,能提高碳、氢、氮测定的稳定性;碳、氢、氮定量限为:0.0086%、0.062%、0.049%。方法应用于煤炭样品和标准品测定,测量精密度C<0.5%、H<2.5%、N<4.0%,标准样品测定结果在允许误差范围内,方法精密度和准确度较满意。

高含H_(2)S和CO_(2)环境下原油集输管道的腐蚀规律研究

原油中H_(2)S和CO_(2)会对管壁产生腐蚀破坏,研究其腐蚀规律可为现场人员制定防治措施提供指导。以长庆油田某原油管道为研究对象,建立了高含H_(2)S和CO_(2)原油管道腐蚀模型,分析了不同因素变化对管道腐蚀规律的影响。结果表明:在现场管道维护与巡检过程中,应着重注意入口端、出口端下降段、出口端爬坡段中部管壁的腐蚀情况;当原油H_(2)S和CO_(2)含量较高时,其含量变化对管道沿程腐蚀状况影响很小;随着原油输送流量的增加,管道沿程腐蚀速率均有一定程度的增大;流体温度在20℃至70℃区间变化对管道沿程腐蚀速率的影响较小,但温度升高至80℃后可有效降低管道的腐蚀速率;原油含水率(体积分数)在10%至70%区间内变化对管道腐蚀速率的影响很小,当原油含水率(体积分数)达到90%后,管道沿程各处腐蚀速率大幅降低。

硫化锌镉制氢光催化剂的研究进展

随着传统石化能源日益耗竭及其带来的环境污染增加,人们正在寻求可替代的、更为清洁的新能源。氢能因其高效、清洁以及广泛应用前景而受到普遍关注。在传统制氢技术中,使用最为广泛的是化石燃料制氢技术。但是,这种技术所造成的能耗和温室气体释放量都非常大。相比之下,光催化制氢技术则是将太阳能转化为氢能,并以化学的形式储存起来。它具有高效转换能力、零碳排放、可持续性和良好的再循环能力等优点,因此成为未来制氢的重要方向。常见的光催化剂包括TiO2、ZnO、ZrO2、CdS等多种金属氧化物和硫化物的半导体材料。其中,金属硫化物因为具有良好的可见光响应、适宜的能带结构、原料丰富和制备简单等优点,被视为一种具备良好光催化性能和实际应用前景的产氢材料。然而,金属硫化物在反应过程中易发生光生载流子复合、光腐蚀等,影响其光催化性能。本文详细阐述了光催剂硫化锌镉的光催化产氢过程,对其产氢性能以及稳定性相关研究进行了总结,并探讨了制约该技术发展的挑战和未来方向。