快速渗氮工艺的试验研究

采用预氧化两段式气体渗氮工艺,充分利用预氧化的催渗作用,达到缩短渗氮工艺周期的目的。     

高锰酸盐复合药剂与氯联合控制消毒副产物的研究

以北方某市受污染水源为研究对象,通过实验考察了高锰酸盐复合药剂(PPC)与氯联合控制消毒副产物-三卤甲烷(THMs)的效果.实验结果表明,1.0mg/L PPC可使预氯化过程中的THMs生成量降低14.1%,pH值为6.0时,PPC显著降低了预氯化工艺的THMs生成量,并且THMs生成量随pH值降低而减少;联合预氧化工艺的THMs生成量与单独预氯化相比降低了17.2%.因此PPC和氯联合可有效降低饮用水的THMs生成.     

熔融制样法对硫铁矿、铜精矿和方铅矿主量元素的XRF光谱测定

采用铂-黄坩埚熔融法制样,对铜精铜、硫铁矿、方铅矿样品中主量元素S、Fe、Cu、Pb等进行X射线荧光光谱测定.采用硝酸钠低温预氧化处理,以偏硼酸锂、四硼酸锂混合物作熔剂,溴化锂作玻璃片脱模剂.结果表明,此法克服了颗粒度效应,避免了铂黄坩埚腐蚀的危险,同时由于它的高度均质化,提高了测量的准确度,测量结果令人满意.     

Effect of air oxidation on coal hydrogenation

Japanese Taiheiyo coal (75.9%C) was oxidized with air at 250 °C for 3–40 h and at 300 °C for 3–10 h. The weight decreased from 16.3 to 46.5% at 250 °C and from 21.7 to 41.3% at 300 °C. Carbon loss and yield of NaOH soluble were obtained. The resultant oxidation products were hydrogenated at 370 °C for 1 h under 10 MPa hydrogen pressure using red mud with sulphur as catalyst and wash oil as solvent. Conversion to pyridine, benzene and n-hexane soluble fraction shows a minimum for the coal oxidized 10 h at 250 °C and for the coal oxidized for 3 h at 300 °C. Initial oxidation makes a network structure which contributes to a reduction in conversion, but in later stages of oxidation, splitting of bridge linkages and/or ring opening of aromatic structures, contribute to increases in conversion.     

Chromium transport through Cr2O3 scales I. On lattice diffusion of chromium

Cr specimens preoxidized at 1100–1300°C to give Cr₂O₃ scales with varying thicknesses and microstructures have been treated at temperature in high vacuum. During the high vacuum treatment the specimens lose weight due to outward Cr transport through the Cr₂O₃ scales. The initial rate of weight loss gradually diminishes, but eventually the weight loss reaches a linear rate. Concurrently the Cr₂O₃ scale exhibits grain growth and densifies. It is concluded that the mode of outward chromium transport gradually changes during the high vacuum treatment: from lattice and grain-boundary diffusion and possibly vapor transport along microcracks during the initial stage to lattice diffusion only for the densified scales. It is concluded that chromium diffuses by an interstitial type mechanism. Self-diffusion coefficients of Cr in Cr₂O₃ at the Cr-Cr₂O₃ phase boundary have been calculated from the linear rates of chromium transport for different defect structure situations.     

三种预氧化剂在水处理中的应用评估

源水的富营养化将严重影响常规给水处理厂的运行,使得出水水质不能保证。为此,开展了KMnO4、H2O2、ClO2 的预氧化研究。结果表明,投加这三种氧化剂均能显著提高对水中藻类、浊度、有机物的去除率,对细菌及大肠菌群也有较好的去除效果,但投加KMnO4 会增加出水色度,采用ClO2 作氧化剂则成本较高,相比之下H2O2 是一种较为理想的预氧化剂。     

KMnO_4预氧化法处理中草药制药废水技术研究

为了提高制药废水的可生化性,采用KMnO4预氧化法对其进行预处理,探讨了反应温度、反应时间、溶液pH值、氧化剂投加量等因素对去除废水中CODCr等污染物浓度的影响,结果表明,最佳反应条件为:KMnO4投加量为13 mg/L,氧化反应温度为60℃,氧化反应时间为25 min,pH值为6,处理后废水各项指标均达到了GB 8978—1996《污水综合排放标准》的要求。预氧化法显著提高了废水的可生化性,有利于后续生化处理的进行。     

胜利油田回注污水处理技术新进展

结合胜利油田分公司油田污水处理现状,介绍了胜利油田污水处理技术进展情况,针对胜利油田污水处理特点形成了污水处理技术系列。同时详细介绍了3项单项技术试验应用情况:①二级气浮除油工艺,提高了除油效果,减少了管网及设备的腐蚀;②针对强腐蚀回注污水实施了电化学预氧化技术,详细介绍了电化学预氧化处理污水技术实施情况;③针对化学驱回注污水,研究、实验了高梯度聚结气浮技术,介绍了高梯度聚结气浮现场试验情况。最后,对今后油田污水处理技术的发展进行了展望。     

高强高模碳纤维用高等规聚丙烯腈在预氧化过程中成环性能的研究

高等规聚丙烯腈可作高强高模碳纤维的原丝,但对其预氧化过程的研究很少.为了对比,采用两种样品:高等规聚丙烯腈(iso-PAN)和无规聚丙烯腈(at-PAN),并用XRD图考察了两种PAN从线形结构过渡到环型结构的变化.为了定量地考察它们的差别,运用了JRG群子统计理论,发现随温度升高,高等规PAN比无规PAN成环越容易,环化程度高,通过计算得知PAN高等规PAN的活化能低于无规PAN,这为制造高强高模碳纤维提供了新的前提材料.     

碳纳米纤维膜的制备及表面浸润性研究

采用静电纺丝法制备聚丙烯腈纳米纤维膜,经不同温度预氧化和碳化后得到碳纳米纤维膜(CNFM),通过FTIR、TG、XRD、SEM、RAMAM等表征手段探究了预氧化和碳化过程中纤维膜结构的变化,并考察了不同阶段纤维膜的表面浸润性.研究表明:PAN纤维膜预氧化温度选定在270～290℃范围较为合适;随碳化温度的升高,碳纳米纤维(CNFs)的类石墨层状结构有序化提高,石墨层间距减小;碳化膜的最大接触角可达158.3°±1.0°,表面呈现超疏水性.