高纯天然石膏水热法制备硫酸钙晶须研究

以高纯天然石膏为原料，加压水热法制备高品质硫酸钙晶须。采用常规分析方法、XRD和扫描电镜等手段分析和表征石膏原料和硫酸钙晶须产品。结果表明，制备硫酸钙晶须的最优条件为：料浆质量分数为6.0%，转晶剂氯化镁加入量为石膏质量的0.05%，硫酸加入量为水体积的1.0%，反应时间为4.0 h，快速过滤干燥即得硫酸钙晶须产品。分析结果表明：硫酸钙晶须长度最大为280.4 μm，最小为19.59 μm，平均长度为80 μm；硫酸钙晶须直径最大为5.86 μm，最小为0.20 μm，平均直径为2.67 μm；通过统计分析可知，长径比范围为10～80。     

高分子铁盐絮凝剂制备及其应用研究

研究了以废铁屑和工业硫酸亚铁为原料,在常压和加热条件下,用氯酸钾作为氧化剂制取聚合硫酸铁(PFS)的工艺条件,并在PFS制备的基础上,合成了聚磷硫酸铁(PPFS)和聚氯硫酸铁(PFCS)。将所制备的聚铁用于污水处理实验,结果表明:用该方法制备的聚铁絮凝剂对实际水样具有较好的混凝处理效果,且制备工艺简单、速度快,从根本上消除了用NaNO_2催化氧化法制备聚铁对环境造成的二次污染。     

聚合硅酸硫酸铝的絮凝性能及改性研究

以硫酸铝、水玻璃和铝酸钠为原料制备了聚合硅酸硫酸铝(PASS),研究了PASS絮凝性能,并利用聚二甲基二烯丙基氯化铵(PDMDAAC)和聚丙烯酰胺(PAM)对PASS进行复合改性。结果表明,PASS絮凝条件选择为加药量40 mg/L,A l/S i为10-20,原水在pH值6.0-8.0有较好的絮凝效果。在最佳絮凝条件下处理低浊水时,其除浊率达到97%,通过加入少量PDMDAAC对PASS改性后能显著减少PASS用量。     

用钛白废酸和废铁屑制备聚合硫酸铁试验研究

利用钛白废酸和废铁屑制备了无机高分子絮凝剂聚合硫酸铁。详细研究了聚合硫酸铁制备过程中各因素对亚铁氧化、三价铁水解和聚合等过程的影响。确定了制备聚合硫酸铁的最佳工艺条件为：(1)氧化过程：pH为1．5，氧化剂与亚铁的物质的量之比为0．3，氧化温度为60℃，氧化时间为3h；(2)聚合过程：硫酸根与全铁的浓度比为1．4，陈化时间为2h。     

硼酸与硫酸镁对硼收率影响的分析

介绍了在硼酸生产工艺中影响硼收率的主要因素。以生产系统中硼酸浓度和硫酸镁两个方面探讨了对硼收率影响的原因，并把分析结果应用于生产实践中，调整了部分工艺参数。证明：调整酸化浓度，控制母液中硼酸含量，硼的收率比以往确有提高，是一种不增加设备，不增加投资的行之有效的方法。     

米糠-硫酸直接浸锰工艺条件研究

以米糠及湘西软锰矿为原料,对米糠-硫酸直接浸锰制备硫酸锰的工艺条件进行了研究。结果表明,米糠-硫酸法浸锰的最佳工艺条件为:浸锰温度250℃,硫酸质量分数50%,浸锰时间75min,米糠用量为软锰矿粉质量的20%,硫酸用量为其理论用量的110%。按该工艺条件浸锰,锰的浸出率可达95%以上。该工艺具有能耗少、生产成本低、锰的浸出率高等优点,为软锰矿的开发利用开辟了一条新途径。     

Poly(pyridine-2,5-diyl)–CuCl2 catalyst for synthesis of dimethyl carbonate by oxidative carbonylation of methanol: catalytic activity and corrosion influence

A -conjugated polymer, poly(pyridine-2,5-diyl) (PPy) was investigated as a support for CuCl₂ in the synthesis of dimethyl carbonate by oxidative carbonylation of methanol. The PPy–CuCl₂ adduct had high catalytic activity which was comparable to that of the homogeneous CuCl₂ catalyst. The adduct caused corrosion of stainless-steel vessels only to minor extent, compared with the homogeneous CuCl₂ catalyst. This PPy–CuCl₂ catalyst was easily recycled by filtration and showed a similar catalytic activity in the third time use. The presence of the -conjugated system in PPy, through which electrons can move, may bring about the high catalytic activity for the oxidative carbonylation of methanol, which involves Cu(II)/Cu(I) redox processes.     

镁盐对印染废水脱色处理研究

用镁盐对印染工业酸性染料和混合活性染料废水脱色处理。考察了pH值和镁盐添加量等对脱色效果的影响，同时将镁盐和亚铁盐的脱色效果进行了比较。实验结果表明：镁盐具有良好的脱色效果，在镁盐添加量为600mg/L，pH值11．0－11．5的条件下，脱色率达91％以上，说明镁盐是一种安全、无毒、无害的“环境友好型”绿色水处理剂。     

高温下 CaS氧化反应特性的实验研究

采用热重等温实验研究了970～1150℃内CaS的氧化反应特性,利用红外光谱仪定量分析反应析出SO2气体,通过亚甲基蓝分光光度法测定固体残留物中CaS的含量.实验研究发现,在970～1150℃内,反应呈先失重后增重趋势,固体残留物中都检测出少量CaS的存在.随温度升高,残留固体样品中CaSO4的质量百分比下降,而CaO的质量百分比上升,SO2析出速率急剧增大,1150℃下SO2的析出速率比970℃下的析出速率高了一个数量级.随O2浓度增大,残留固体样品中CaSO4的质量百分比和SO2析出速率轻微上升.降低反应温度和增大O2浓度,有利于提高CaS氧化生成CaSO4的比例.     

The partition coefficients of ethylene between hydrate and vapor for methane + ethylene + water and methane + ethylene + SDS + water systems

The hydrate formation of CH₄+C₂H₄ mixture was studied experimentally in two different cases, with and without the presence of sodium dodecyl sulfate (SDS) in water. The results manifested that the presence of SDS could not only accelerate the hydrate formation process, but also increase the partition coefficient of ethylene between hydrate and vapor drastically. The partition coefficients of ethylene between hydrate and vapor for methane + ethylene + water with the presence of 500 ppm SDS in water were then systematically measured. The experimental temperature ranged from 273.15 to 278.15 K, the pressure ranged from 2.5 to 5.5 MPa, the initial gas-liquid volume ratio ranged from 95 to 240 standard volumes of gas per volume of liquid, and the mole percentage of ethylene in feed gas mixture ranged from 5.28% to 79.36%. The results demonstrated that ethylene could be enriched in hydrate phase and partition coefficients were increased with the presence of SDS in water. This conclusion is of industrial significance; it implies that it is feasible to recover ethylene from gas mixture, e.g., various kinds of refinery gases or cracking gases in ethylene plant, by forming hydrate.