The microwave pyrolysis assisted by absorbers can achieve clean and efficient conversion of coal, and numerical simulation techniques are often employed to further optimize the properties of the resulting products. In this study, the electromagnetic field energy conservation equation, the solid heat conduction equation and the geometric model were coupled, and the COMSOL software was used to establish an electromagnetic-heat transfer model to analyze the microwave pyrolysis reaction of low-rank coal assisted by absorbers. The distribution characteristics of the electric field in the microwave cavity and the temperature field of the coal sample under the effects of different types of absorbers, namely, bluecoke（BC）, Fe 2 O 3 and Fe 2 O 3 /BC were investigated via the electromagnetic-heat transfer model, and the results were verified via comparison with the coal microwave pyrolysis experiments. The results show that the absorber type has no significant effect on the location and shape of the distribution area of the electric field of the microwave cavity and the temperature field of the coal sample. However, the absorber type has a strong impact on the distribution area and intensity, and the impact of the absorber from large to small follows the order Fe 2 O 3 /BC, BC, Fe 2 O 3 . The trend of temperature distribution of coal sample is higher on the right and lower on the left, and the shape of high temperature area is pinnate. Among these absorbers, the intensity of electric field of Fe 2 O 3 /BC is highest, which is 9.79×10~4 V/m, meanwhile, the distribution area of temperature field and highest temperature of coal sample also are highest. The simulated temperature rise characteristics of the three absorbers are similar to the experimental results. However, the difference between the highest and final temperature of the simulation results and experimental results is the smallest under Fe 2 O 3 absorber conditions, and the simulated temperature-rising curve under Fe 2 O 3 absorber conditions exhibites a good agreement with the experimental results.

以低值兰炭末为原料,通过酸洗和微波活化制备了改性多孔兰炭末(MA-BC),并对其吸附处理模拟含Cr(Ⅵ)废水进行了实验研究.采用SEM、N2吸附-脱附测试和FT-IR等分析表征手段对比分析了改性前后兰炭末表面形貌、结构和官能团组成变化.在吸附处理模拟含Cr(Ⅵ)废水实验中,分别考察了 MA-BC投加量、模拟废水pH、初始Cr(Ⅵ)浓度、吸附时间对模拟废水中Cr(Ⅵ)去除效果的影响,并对模拟废水中Cr(Ⅵ)吸附过程进行了动力学和热力学分析.结果表明:经酸洗微波加热活化处理的兰炭末比表面积增大到160.69 m2/g,改性后兰炭末表面的—OH、C=C和—CH3等官能团含量明显增加.在模拟废水Cr(Ⅵ)初始浓度为100 mg/L,pH为2,MA-BC投加量为2 g,吸.附时间210 min的最佳工艺条件下,模拟废水中Cr(Ⅵ)去除率可达到89.21％.该吸附过程以化学吸附为主,服从准二级动力学方程,并符合Langmuir吸附等温线模型,理论吸附量为6.255 mg/g,与实验所测的平衡吸附量相吻合.吸附饱和的改性多孔兰炭末经5次循环再生-吸附,对模拟废水中Cr(Ⅵ)去除率仍保持在80％以上.

生物质协助低阶粉煤微波热解可改善热解产物的分布和特性,尤其是油气收率和品质.采用四因素四水平正交实验法研究了微波功率(420W,280 W,700 W,560 W)、热解时间(30min,20min,10min,40min)、玉米芯粒径(0.250 mm～0.420 mm,0.177 mm～0.250 mm,0.841mm～1.680mm,0.420 mm～0.841 mm)和玉米芯添加量(10％,40％,30％,20％,质量分数)对低阶粉煤与玉米芯微波共热解中焦油收率的影响,对比分析了低阶粉煤、玉米芯单独微波热解和微波共热解的升温特性和产物特性.结果 表明:影响焦油收率由主到次的因素分别为玉米芯添加量、微波功率、玉米芯粒径、热解时间.在本实验参数范围内,正交实验得到的最佳工艺条件为:微波功率700W、热解时间40 min、玉米芯粒径0.841 mm～1.68 mm、玉米芯添加量40％,此时的半焦和气体产物收率分别为51.22％和32.17％,焦油收率达到最大,为8.85％.与低阶粉煤单独微波热解相比,微波共热解生成的焦油中轻油含量提高了11.89％,而杂原子化合物含量降低了7.09％,实现了热解焦油的轻质化和高品质化.

煤炭在我国能源结构中占据着举足轻重的地位,但其主流利用方式存在较大的能源浪费和环境污染等问题.生物质作为绿色可再生能源,具有廉价、挥发分高、氢碳比高等特点,但由于缺乏合理的有效利用,导致生物质中大量的氢组分被低端消费,造成不必要的资源浪费.将低变质煤与生物质共热解,不仅改善了低变质煤的热解特性,提高了热解产品收率和质量,而且充分利用了生物质资源,缓解了环境污染,实现低变质煤资源和生物质资源高效清洁分级提质利用的"双赢".目前,国内外在低变质煤和生物质共热解领域的研究主要集中在热解工艺优化、热解产品分布规律、共热解协同机制等方面.大量研究结果表明,热解温度、升温速率、生物质组成等因素会对共热解产物分布、产物收率及质量产生影响.此外,与传统热解相比,新型热解方式(如微波热解、红外热解等)均能显著提高热解效率,有效改善热解产物收率和质量,已引起国内外学者的高度关注.本文全面分析了农林产物、藻类、禽畜产物、城市垃圾等四类不同生物质供氢体协助低变质煤加氢热解反应的产物特性,探讨了共热解过程中碱金属的催化作用、自由基反应和挥发分的二次反应等协同作用机制,介绍了新型微波热解、红外热解技术进展及特性.最后,展望了生物质供氢体协助低变质煤加氢共热解的发展前景.

本文依据"新工科"教育的战略思想,结合我校参加全国化工设计竞赛的经验,修订化学工程与工艺专业的培养方案,以培养学生工程设计能力与创新创业能力为目标,提升学生的综合素质,制订了符合"新工科"型人才培养的化工设计类课程体系的培养计划,通过优化课程设置,改革教学内容的深度和广度,实施工程案例教学模式,使新的培养方案更符合"新工科"的要求,体现实用和时代性.

以PRBs技术中最为关键的填充反应介质为研究对象,介绍了常用的五种反应介质(零价铁、活性炭、无机矿物、黏土、和以固体废弃物为前体材料的反应介质)的研究现状,阐述了影响反应介质选择的主要因素,同时介绍了PRBs技术在实际工程应用中的典型案例,并对PRBs技术的现存问题和未来发展进行了总结和展望,以期为研发长期高效和环境友好型的PRBs反应介质提供有益的支持.

新型电池和电解水技术具有清洁、能量转化效率高等优点,其核心是阳极的析氢反应(HER)或氧还原反应(ORR)和阴极的析氧反应(OER).然而,在这些反应中,电催化材料的研发是关键.随着新型碳材料的发现以及非贵金属在新能源领域的广泛研究与应用,电催化材料也从最初的贵金属单一材料,发展到转化效率高、抗毒性强、经济性好的碳基复合材料,其性能、结构、成本、制备工艺等各个方面都有了质的飞跃.电催化剂的设计关键在于增加催化剂表面活性位点和自由电子的移动.通过改变材料形状、调整材料粒径和制备复合材料等方法来增大比表面积,从而增加活性位点的数量,也可以将催化剂制成多晶、核壳和合金结构以提高材料表面自由电子的移动.石墨烯、碳纳米管、介孔碳等新型碳纳米材料具有稳定性好、孔隙可调、比表面积高、导电性能优异等优点,是良好的复合基体材料;而非贵金属,尤其是铁、钴、镍、铜、钼,具有电催化活性高、稳定性好、抗毒性强、成本低等优点,可作为催化活性组分.将非贵金属负载到新型碳基体材料上,增加碳纳米材料的电子不对称密度或打破碳表面的电中性,形成更多的吸附活性位点,也更有利于SP2杂化碳表面π电子的自由移动,使得复合材料的电子分布和空间结构得到改变,从而有效地提高复合材料的电催化活性.本文首先归纳了碳基非贵金属电催化剂的国内外研究进展;其次,分别对碳基非贵金属电催化剂的碳基体材料和催化活性组分进行对比分析;最后,总结了碳基非贵金属电催化剂的发展优势和存在的问题,并展望其前景.

为解决丙烯酸高碳酯常规工艺合成过程中出现的收率低、控温不准确、生产不连续、副反应多、后处理难等问题,以微通道反应器合成丙烯酸十四酯为主要研究对象,结合红外光谱、核磁共振、沸点、折光率及偏光显微镜等手段对成品酯进行分析表征,系统考察了醇/酸摩尔比、反应温度、进料流量、催化剂及阻聚剂添加量等对丙烯酸十四酯收率的影响.结果表明:随着醇/酸摩尔比的减小,油浴加热温度升高,进料流量、催化剂和阻聚剂添加量的增大,丙烯酸十四酯的收率基本上呈现先增加后减小的趋势;在进料醇/酸摩尔比为1:1.2、高温循环器油浴加热温度为150℃ 、催化剂对甲苯磺酸与阻聚剂对苯二酚添加质量分数分别为0.8％ 和0.6％ 、甲苯与十四醇质量比为0.8、进料流量为0.3 L/min优化工艺条件下,采用微通道反应器进行催化合成丙烯酸十四酯的收率最大,达到92.4％,而常规间歇式反应器在相似工艺条件下,丙烯酸十四酯的收率仅为82.0％,且反应时间更长;丙烯酸十四酯与油品中蜡晶具有相似的结晶形态,有利于其相互融合,产生共晶,从而表现出降凝功效.

为了给X100钢在工程中的应用提供数据参考,采用电化学方法,选用典型模拟碱性土壤溶液,通过改变Cl-浓度、浸泡时间以及极化恒电位值,研究X100钢的电化学腐蚀行为.结果 表明:X100钢的腐蚀为活化-钝化过程,其交流阻抗谱包括高频容抗弧和低频容抗弧,在低频段出现Warburg阻抗;Cl-浓度从0.15 mol/L增大到0.25mol/L时,溶液中的电荷转移电阻增大,反应形成的钝化膜越来越致密,导致腐蚀速率减小;浸泡时间从2h增加到8h时,电荷转移电阻减小,导致电极表面腐蚀加剧;在-0.60～0.40 V极化扫描下,电荷转移电阻明显增加,钝化膜变得致密,导致腐蚀抗力增大,腐蚀速率减小.

为了给油气田的腐蚀防护方案和研究方向提供借鉴,采用动电位极化曲线、交流阻抗谱以及扫描电镜(SEM)等手段研究了静止、流动2种状态下Cl-浓度对X100钢腐蚀行为的影响.结果 表明:流动状态改变不影响动电位极化曲线阴阳极反应机理;但和静止状态相比,流动的液体加速了腐蚀产物的迁移,并且增加了电极表面的剪切力,破坏了腐蚀产物层,增加了电极表面侵蚀离子的接触几率,使电极表面腐蚀点增多,腐蚀面积更大,腐蚀速率大幅度提高;阻抗谱对比研究发现,流动状态下的液相传质速度增加,溶液和电极表面之间离子浓度迅速达到均匀分布,导致Warburg阻抗消失,最终流体力学因素与腐蚀电化学因素共同作用,促进了流动状态下的腐蚀,使得腐蚀速率是静止条件下的200多倍,达到58.365 mm/a.

The corrosion behavior of X90 pipeline steel in simulated soil solution with different pH values was investigated by potentiodynamic polarization,AC impedance spectroscopy and corrosion weight loss test.Result showed that the change of pH value did not affect the mechanism of anode and cathode reaction of X90 steel.Alternating current impedance spectroscopy of X90 steel showed that:when pH ≤4,the impedance arc appeared in low frequency region,and during this process,the adsorption or pitting nucleation existed;when pH ≥4,the Warburg diffusion impedance appeared,and the main control step was mass diffusion.With the decrease of solution pH value,the corrosion current density increased,and the total Fe content in solution was improved,as well as the corrosion of sample surface became more serious,which all indicated that the corrosion rate of X90 was improved.

针对陕西汉中某地钒钛磁铁矿金属化球团,采用锥形球磨机为湿法磨矿设备,研究了磨矿碱度对铁粉再氧化的抑制规律,考察了磁选工艺参数对磁选分离效果的影响,并采用扫描电子显微镜(SEM)和X射线衍射仪(XRD)对产物进行分析表征.结果表明,随着磨矿时间延长,矿粉颗粒逐渐降低,均匀度增大,矿物解离度提高;矿粉铁品位随着磨矿碱度提高呈现先增大后降低的趋势,在pH值为13时达59.3％.磨矿粒度-74 μm为95.2％,磁选强度60 mT时获得较好的磁选效果,所得磁性精矿产物中铁品位84.9％,钒钛品位分别为0.52％和3.54％,有效实现了铁与钒钛的分离.磁性精矿产物中主要以金属铁为主,非磁性产物中主要由Fe3Ti3O10、FeVO4、CaTiSiO5、Mg1.2 Ti18O5等物相组成.

The influences of chloride ions and stress on the electrochemical corrosion behavior of X80 pipeline steel in solution with high pH value were discussed by potentiodynamic polarization and electrochemical impedance spectroscopy.Results showed that the passivation of X80 pipeline steel was influenced by Cl-concentration.When the Cl-concentration was less than 0.10 mol/L,a stable passive film was formed on X80 pipeline steel.When the Cl-concentration was more than 0.10 mol/L,no stable passive film was generated.Under the free-corrosion potential,a small amount of Cl-could increase the corrosion tendency of X80 pipeline steel,but a large amount of Cl-would reduce the corrosion tendency.Besides,the second capacitive arcs appeared in the low-frequency area of alternating current impedance because of applied stress,and the applied stress could accelerate the dissolution rate of X80 pipeline steel under free-corrosion potential.

采用D311树脂吸附处理含高铜氰化提金尾液,分别考察了树脂添加量、吸附反应时间、反应温度、溶液pH等对铜氰络合离子吸附率的影响,获得了静态吸附最优工艺条件,并从热力学及动力学角度研究了D311树脂对铜氰络合离子的吸附特征.结果表明:当D311树脂吸附经硫酸铜沉淀预处理后的提金尾液时,在液固比(滤液与树脂体积比)为5:1、溶液pH ＜9、室温、吸附反应时间135 min的优化工艺条件下,其对铜氰络合离子的吸附率可达98％以上.该吸附过程符合Freundlich吸附模型,为优惠吸附;吸附过程的速度控制步骤为颗粒扩散和化学反应共同控制.采用准一阶动力学模型和准二阶动力学模型分别对吸附动力学数据进行模拟,发现D311树脂对含高铜氰化提金尾液中铜氰络合离子的吸附符合准二阶动力模型,其理论吸附量为12.6023 mg·ml-1,与实验所测的平衡吸附量吻合,吸附速率常数k=1.236×10-2 min-1.

以兰炭末为原料采用KOH高温活化法制备活性炭,重点研究了活化温度对活性炭结构与性能的影响.采用SEM、红外光谱对活性炭的表面形貌及表面结构进行表征.研究表明,随着活化温度的升高,活性炭的收率逐渐减小,碘吸附值先增大后减小.当活化温度为800℃时,活性炭的收率为70％,碘吸附值最大可达到733.482mg/g.SEM及FI-IR分析表明,高温下KOH的扩孔作用主要由表面向活性炭的内部纵深发展,最终会使活性炭形成规则的层状、蜂窝状孔隙结构,并且表面含有大量的羟基、羰基等活性基团.

煤的微波热解是一种新型煤热加工工艺.本文主要研究了在氮气气氛环境下煤的微波热解.结果表明:氮气气氛下微波热解效果要好于隔绝空气热解;热解微波功率影响热解反应的终温,微波功率越高,则终温越高,热解产品的产率和质量就越好;气氛流量对热解固体产物产率有较小的影响,但对液态产物影响较大.

煤-循环煤气微波共热解是煤清洁高效转化利用的一种新技术.为深入剖析其作用机理,主要研究了二氧化碳气氛中低变质煤的微波热解过程,系统考察了微波功率、热解时间、气体流量和煤样粒度等因素对热解产品收率、组成及煤气成分的影响.结果表明:CO2加剧了低变质煤的微波裂解程度,使原煤中挥发分析出较多,有机质分解加快,兰炭中矿物质有效富集.在微波功率960 W、热解时间40 min、CO2流量0.56 L/min、低变质煤样粒度5～10 mm的优化工艺条件下热解,兰炭收率最高可达60.8％,液体产品(煤焦油和热解水)收率最高可达21.8％,煤气中有价成分(CO+CH4+H2)体积分数达54.03％.所得兰炭中固定碳含量达84.89％,满足FC-4级兰炭标准;挥发分含量为4.86％,满足V-1级兰炭标准.所得煤焦油中烷烃类化合物含量高达35.5％.

Trea tment of gold mine wastewater with the characteristics of cyanide,high copper,iron by the chemical precipitation-electric adsorption combined technology,the analyzed and discussed were focused on the reaction principle,the technological process and the result of the reaction.Research shows that the method is viable to treatment wastewater containing high concentration of cyanide.After precipitation by ZnSO4,the precipitation rate of free cyanide,Fe and Cu in wastewater were 100%,85.89% and 99.43%,respectively.After advanced treatment by electric adsorption,the removal rates of Cu,thiocyanate,and free cyanide were 98.68%, 43.60% and 99.57%,respectively.The XRD analysis showed that the sediment from zinc sulfate precipitate mainly includes Zn2 [Fe(CN)6],Zn(CN)2 and CuCN,and the sediment from the electric adsorption is mainly CuSCN. Sediment and the anode plate after saturated adsorption can be comprehensive treatment and recovery of cyanide and metal,and the wastewater can be returned to the leaching system for recycling at the same time.

采用硫酸锌沉淀工艺处理某黄金冶炼厂的高铜氰化提金废水,考察了沉淀剂用量、沉淀时间及沉淀温度对各离子沉淀率的影响,采用X射线衍射(XRD)分析对沉淀物进行分析表征,并对沉淀过程进行了理论分析和计算.研究表明,沉淀时间和温度对沉淀效果影响不大,而硫酸锌用量的影响较为显著.随着硫酸锌用量的增加,废水中游离氰与Cu离子浓度逐渐减小,Zn离子浓度逐渐增加.在100 ml氰化废水加入3.5 g ZnSO4,常温搅拌40 min的条件下,Fe,Cu离子及游离氰的沉淀率分别可达到100％,86％和99.34％.沉淀过程溶液中金基本没有损失,处理后的废水可在调节pH值后直接返回浸出系统循环利用.XRD分析表明,硫酸锌用量对沉淀物的组成没有影响,沉淀物组分主要为Zn2[Fe(CN)6],Zn(CN)2和CuCN,可进一步通过化学方法处理综合回收金属铜、锌与游离CN-.理论计算表明,溶液中游离的CN-,Fe及Cu离子沉淀的极限浓度分别为3.83×10-,1.56×10-13和2.37 mg·L-1,而处理后废水中的离子实际浓度要高于理论极限浓度,离子的沉淀次序依次为Zn离子、Fe离子、游离CN-和Cu离子.