净化湿法磷酸产品中硫含量偏高的原因分析及对策

简单介绍了湿法磷酸净化工艺,分析了用湿法磷酸净化工艺制得工业级磷酸中硫含量偏高的原因:①原料磷酸质量不稳定;②原料酸中固含量偏高;③磷酸预处理反应时间不足;④磷酸预处理反应温度偏低;⑤板框压滤机操作不当;⑥萃取控制不当。为此特增设了60 m3的原酸储槽,严格控制原酸流量为1.0 m3/h,反应温度60~70℃,同时加强了板框压滤机的操作及清洗等措施,使预处理工序的脱硫率达到88%以上,满足了预处理工序的脱硫要求。     

2,6-二(4-氯甲酰苯氧基)苯甲腈的合成与表征

在KOH及DMSO的存在下,先将对羟基苯甲酸(p-HDBC)与2,6-二氟苯甲腈(DFBN)进行缩合反应生成2,6-二(4-羧苯氧基)苯甲腈(BCPOBN),BCPOBN与氯化亚砜反应,得到2,6-二(4-氯甲酰苯氧基)苯甲腈(BClPOBN).     

Graft polymerization of acrylic acid onto polyphenylene sulfide nonwoven initiated by low temperature plasma

Graft copolymerization of acrylic acid (AA) onto polyphenylene sulfide (PPS) nonwoven initiated by low temperature plasma was studied. The effects of various conditions on graft reaction and the grafting rate were investigated. SEM images showed that PPS nonwoven was grafted, and the graft copolymerization only occurred on the surface of PPS. It may be due to the chain transference going with the graft copolymerization. It was found that with the increasing of plasma power, treatment time, space between electrodes, monomer concentration, and temperature of graft polymerization, the grafting rate increased at first, went to the top, and then decreased. The PPS nonwoven surface graft reaction could be optimized by the following processing conditions: 120 s of plasma treatment time, 50 W of plasma power, 1.5 cm of space between electrodes, 30% (w/w) of monomer concentration, and 50°C of temperature of graft polymerization. Measurement of XPS showed that the peak of C1s of graft polyacrylic acid was existed, and the peak area increased with the increase of the grafting rate. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 5884–5889, 2006     

The effects of Ni and Li doping on the performance of lithium manganese oxide material for lithium secondary batteries

Layered Li_0.7[M_1/6Mn_5/6]O₂ (M=Li, Ni) was synthesized using a sol-gel method. P2-Na_0.7[M_1/6Mn_5/6]O₂ precursor was first synthesized by a sol-gel method, and then O2-Li_0.7[M_1/6Mn_5/6]O₂ was prepared by an ion exchange of Li for Na in P2-Na_0.7[M_1/6Mn_5/6]O₂ precursor. From charge/discharge curves, it was seen that Li_0.7[Li_1/6Mn_5/6]O₂ has two plateaus similar to those observed from a spinel structure, but Li_0.7[Ni_1/6Mn_5/6]O₂ holds a single plateau as observed from a typical layered structure. It was considered that Li_0.7[Li_1/6Mn_5/6]O₂ undergoes a phase transformation from layered to spinel structure during the charge/discharge cycle, but Li_0.7[Ni_1/6Mn_5/6]O₂ maintains O2-layered structure after the cycles. Li_0.7[Ni_1/6Mn_5/6]O₂ was higher in discharge capacity and retention rate than Li_0.7[Li_1/6Mn_5/6]O₂.     

多元杂多酸在仲辛醇制己酸中的催化作用

采用磷、钼、钒系列多元杂多酸作为硝酸氧化仲辛醇制己酸的催化剂,对其催化性能和选择性进行了实验研究。结果表明:H6PMo9V3O40、H10PMo5V7O40、H11PMo4V8O40等多元杂多酸均可提高仲辛醇的转化率、己酸产率和己酸选择性,并确定了这3种催化剂的最佳用量:当它们分别为仲辛醇质量的1 4%、1 0%、1 4%时,仲辛醇转化率可达98 3%、97 6%、100%;己酸的选择性可达85 7%、85 8%、78 8%;其性能明显优于钒催化剂。     

异辛酸合成液的气相色谱分析

建立了异辛酸合成过程中异辛醇、异辛酸和酯的气相色谱分析方法。以 10 %改性聚乙二醇 2 0M为固定液 ,苯乙酮为内标物 ,氢火焰离子化检测器 ,内标法定量分析异辛酸。实验结果表明 ,该方法准确可靠 ,测得异辛酸的相对重量校正因子 1.30 5 ,相对误差小于 2 .0 %。同时通过与化学法对照结果显示 ,合成液用内标法测定较好 ,而精产品用带校正因子的归一化法测定较好。     

己内酰胺生产的绿色化

己内酰胺生产的绿色化关键是环己酮肟贝克曼重排工艺路线替代的开发。重点介绍了代替浓硫酸催化该反应的固体酸催化剂、催化剂的失活与再生、反应器工业化的方法的进展。提出采用多相催化剂取代发烟硫酸使环己酮肟转化为己内酰胺的工艺 ,该催化剂具有转化率和选择性高 ,易处理再生 ,且可用于连续化工业生产     

地老虎性信息素类似物E－7－十五碳烯－1－醇乙酸酯的合成

以紫胶桐酸为原料，经三步反应合成了地老虎性信息素类似物Ｅ－７－十五碳稀－１－醇乙酸酯。关键步骤是１６－羟基－９Ｅ－十六碳烯酸（２）在ＤＢＵ作用下的脱羧反应。     

混酸冲洗滤盘的可行性

湿法磷酸生产中，均以水为介质冲洗倾覆盘式真空过滤机的滤盘，为实现系统的污水零排放，提高倾覆盘式真空过滤机的生产能力，提出以回磷酸和硫酸配制成混酸去冲洗滤盘的方法。分析了采用该方法的诸多优点及注意事项，指出安全生产问题须认真落实。     

氯乙酸异辛酯合成研究

以氯乙酸、异辛醇为原料，固体超强酸作催化剂，在减压条件下合成了氯乙酸异辛酯。考察了各种因素对酯化率的影响，得出最佳条件为：异辛酯与氯乙酸的摩尔比1．0：1．0，固体超强酸催化剂SA的用量为反应物总质量的0．5％，反应时间为3h，真空度为95-98kPa，酯化率达99．6％(以氯乙酸计)。自制SA催化剂催化活性稳定，不腐蚀设备，无环境污染，可多次重复使用，催化活性基本不变。