四乙基溴化铵相转移催化合成N，N－二乙基苯胺的研究

在常压下以四乙基溴化铵作相转移催化剂合成制得Ｎ，Ｎ 二乙基苯胺，研究了各反应因素对目的产物产率的影响，其优化工艺条件为：在５０ｍｌ５０％的氢氧化钠溶液中，苯胺和溴乙烷的摩尔比为１∶２，四乙基溴化铵用量为０２５ｇ，６０℃下常压反应７ｈ，产品产率为８１５％。     

四乙基溴化铵相转移催化合成N，N－二乙基苯胺的研究

在常压下以四乙基溴化铵作相转移催化剂合成制得Ｎ，Ｎ二乙基苯胺，研究了各反应因素对目的产物产率的影响，其优化工艺条件为：在５０ｍｌ５０％的氢氧化钠溶液中，苯胺和溴乙烷的摩尔比为１∶２，四乙基溴化铵用量为０２５ｇ，６０℃下常压反应７ｈ，产品产率为８１５％。     

三乙醇胺催化合成正丁基苯基醚

采用３．０ｇ三乙醇胺为相转移催化剂,在６．０ｇ氢氧化钠,１．０ｍｌ水存在下,将０．１ｍｏｌ苯酚和０．２ｍｏｌ溴丁烷回流反应２．０ｈ,得正丁基苯基醚,收率为９２．０％     

三乙醇胺催化合成正丁基苯基醚

采用３．０ｇ三乙醇胺为相转移催化剂,在６．０ｇ氢氧化钠,１．０ｍｌ水存在下,将０．１ｍｏｌ苯九０．２ｍｏｌ溴丁流反应２．０ｈ,得正丁基苯基醚,收率为９２．０％。     

试纸法快速测定溶液中的银离子

用重金属离子含量低的定量滤纸，依次在硝酸镉、硫化钠溶液中浸渍，晾干后，用于测定溶液中Ａｇ＋。Ａｇ＋浓度在０～１０ｇ／Ｌ时，直接用色阶比较法，检出限０．２９／Ｌ；Ａｇ＋含量低于０．１ｇ／Ｌ时，可使用简单微型装置，２０ｍｌ样品的检出限可达０．２５ｍｇ／Ｌ。几种测定方法比较，结果一致。     

流动注射光度法测定水中痕量镉

用苯重氮氢基苯对偶氮苯作显色剂建立了测定痕量镉的流动注射分光光度分析法。在四硼酸钠－氢氧化钠溶液作载流的缓冲介质中，当乳化剂ＯＰ存在时，笨重氮氨基苯对偶氮苯与镉形成的红色配合物的吸光度在０．０４～０．４０μｇ／ｍｌ范围内呈良好的线性关系。考察了各种实验条件，方法简单、选择性好，进样体积为１００μｌ，测样频率每小时为７６次。在室温条件下，检出限达到０．００６μｇ／ｍｌ。对０．１２８μｇ／ｍｌ镉的１１次检测，变异系数为１．５％。平均回收率为１００．３％。方法用于水中镉的测定，结果良好。     

分析纯钼酸钠的生产新工艺

分析纯钼酸钠的常规生产工艺是将钼精矿氧化焙烧制得三氧化钼（简称钼焙砂）,用氢氧化钠溶液浸出,制得工业钼酸钠,将工业钼酸钠重结晶后再溶于水,加硝酸沉淀出三氧化钼的二水合物,充分洗涤后进行干燥,再于７００℃升华制得高纯三氧化钼,将其溶解于纯氢氧化钠溶液中...     

由工业碲制备高纯碲

本文介绍了一种制备高纯碲的方法，即先用浓ＨＮＯ３与工业碲（９９％）反应制得ＴｅＯ２，再用ＮａＯＨ溶液溶解ＴｅＯ２得Ｎａ２ＴｅＯ３溶液，用Ｎａ２Ｓ净化后，加Ｈ２Ｏ２溶液得Ｎａ２ＴｅＯ４沉淀，最后用盐酸溶解Ｎａ２ＴｅＯ４，通ＳＯ２气体得９９．９９９％的高纯碲     

壳聚糖作为固定化酶载体的应用研究

壳聚糖属于天然高分子物质,具有来源丰富、机械性能好、化学性质稳定、耐热性好等特点,特别是含有氨基,既易于与酶共价结合,又可结合金属离子,使酶对金属离子的抵抗能力得到加强,同时又容易通过接枝而改性,可望作为固定化酶的良好载体。因此,笔者对壳聚糖吸附法、交联法和共价接枝法固定化α淀粉酶进行了详细的研究,为提高机械稳定和可操作性对壳聚糖进行了改性,取得了满意的结果。吸附法固定：取１０ｇ壳聚糖,溶于５００ｍｌ１％冰醋酸溶液,加入１％氢氧化钠溶液调节到ｐＨ８０,过滤,抽干得白色粉末。加入１％α淀粉酶…     

相转移催化合成N,N—二乙基邻乙基苯胺的研究

在常压下以三乙基苄基氯化铵作相转移催化剂合成制得Ｎ,Ｎ－二乙基邻乙基苯胺,研究了各反应因素对目的产物产率的影响,其优化工艺条件为：在５０ｍｌ５０％的氢氧化钠溶液中,邻乙基苯胺和溴乙烷的摩尔比为１：２．６,三乙基苄基氯化铵用量为０．５０ｇ,反应回流时间１８．０ｈＮ,－烷基化反应的收率为５７．５％。     

氟硅酸钾滴定法测定粗制氟化钠中二氧化硅

采用硝酸-氢氟酸混合酸为消解溶剂,通过微波消解技术对粗制氟化钠进行快速消解,并用氟硅酸钾滴定法测定其二氧化硅含量。选择饱和氯化钾溶液替代固体氯化钾作为沉淀剂,考察了消解酸体系、饱和氯化钾溶液用量、沉淀温度、沉淀放置时间、共存元素干扰及指示剂选择等条件对测定结果的影响并进行优化。确定了最优测试条件：以8 mL硝酸+2 mL氢氟酸为消解溶剂,以8 mL饱和氯化钾溶液为沉淀剂,控制沉淀温度为20~25 ℃、沉淀放置时间为15 min,选择50 g/L氯化钾-50%乙醇溶液洗涤沉淀,采用溴麝香草酚蓝-酚红指示剂。该方法应用于回收粗制氟化钠中二氧化硅含量的测定可大幅度缩短分解试样的时间,有效降低检测成本,回收率为99.15%~100.63%,相对标准偏差（RSD,n=8）小于1%,与传统高温碱熔法测定结果相符,方法的准确度和精密度较好。     

Demethylation and Nitration of Lignin

Abstract

The formation of methanol during treatment of wood meal with nitrogen dioxide is favored by the presence of oxygen and suppressed by addition of sodium sulfate. With 0.5% of added nitrogen dioxide large amounts of methanol were produced at 70°C when kraft lignin was impregnated with 0.5M nitric acid. A markedly increased formation of methanol and nitro groups in the lignin occurred when sodium nitrate was added. At low acidity the effect of sodium nitrate was insignificant. In a solution which was 0.5 molal with respect to nitric acid and 0.8 molal with respect to sodium nitrate, appreciable amounts of methanol and nitro groups were produced even when no nitrogen dioxide was added. This is explained by a generation of nitrogen dioxide from nitric acid in a autocatalytic process favored by high concentrations of nitrate and hydrogen ions.     

3-氨基吡唑-4-甲酰胺半硫酸盐的合成

以原甲酸三乙酯、丙二腈为起始原料,合成乙氧亚甲基丙二腈(Ⅰ),将其加入80%水合肼中,加热回流,生成3-氨基-4-甲酰胺吡唑(Ⅱ),将其与浓硫酸混合,调节pH值,40℃下搅拌0.5 h,经过滤,重结晶,得到目标化合物3-氨基吡唑-4-甲酰胺半硫酸盐(Ⅲ),总收率63.7%(以丙二腈计)。目标化合物结构经红外光谱、核磁共振分析验证。     

Processing and kinetics studies on the alumina enrichment of coal fly ash by fractionating silicon dioxide as nano particles

Coal fly ash produced in the northern China is a potential bauxite substitute for aluminum production because of its high alumina content. However, this industrial application has been limited for its high silicon content. Alumina enrichment by removing silicon becomes a key technology for its utilization. A novel process was developed to fractionate the coal fly ash into high purity nano silicon particles and aluminum enriched residual ash. The procedure has major steps as sodium silicate dissolution with sodium hydroxide, first carbonation to remove impurities, second carbonation to precipitate silicon, and silicon precipitate recovery as a mesospheric nano particles product. Morphological and X-ray diffraction evidences indicated the glassy amorphous silicon content of the ash was dissolved in the sodium hydroxide solution whereas mullite remained in the residue. Kinetics study indicated that the second carbonation was a kinetically second order medium fast multi-phase reaction in which sodium silicate was precipitated as silicic acid. It was found that the reaction was controlled by the mass transferring resistance in the liquid membrane. These nano silicon dioxide particles were in size of 50 nm with a purity of 96%. Alumina content in process residue was slightly increased from 42.00 to 49.20%. Silicon dioxide content was reduced from 48.89 to 30.26%. Ratio of alumina/silica was increased from 0.86 to 1.63.     

对氨基苯甲磺酰吡咯烷的制备

以氯苄为主要原料制备了对氨基苯甲磺酰吡咯烷(Ⅰ)。以V〔w(HNO3)=95%的发烟硝酸〕∶V〔w(游离SO3)=22%的发烟硫酸〕=1∶1 3的混酸对氯苄进行硝化,反应温度为0℃,反应2h,得对硝基氯苄(Ⅱ),产率52%;Ⅱ用亚硫酸钠磺化,在V(甲醇)∶V(水)=1∶1 5的溶剂中,回流反应18h,得到对硝基苯甲磺酸钠(Ⅲ),产率96%;Ⅲ用PCl5氯化,得到对硝基苯甲磺酰氯(Ⅳ),产率78%;Ⅳ经吡咯烷氨解,反应物料比为n(Ⅳ)∶n(吡咯烷)=1∶2,以二氯甲烷为溶剂,常温反应10h,得对硝基苯甲磺酰吡咯烷(Ⅴ),产率达到98%;Ⅴ用铁-盐酸还原,在V(乙醇)∶V(水)=1∶1的溶剂中回流1h,得对氨基苯甲磺酰吡咯烷,经HPLC分析,精制后的产物纯度w(对氨基苯甲磺酰吡咯烷)=99 2%,产率85%,总产率32 4%。     

ICP-OES方法测定低合金钢中多元素两种消解方法比较

研究了用稀硝酸溶样,高氯酸发烟氧化[1]后,用盐酸硝酸酸化试液,在ICP光谱仪上进行元素测定,以及用稀硝酸溶样、加硫酸磷酸混合酸发烟后,加水溶解盐类测定试液,在ICP光谱仪上进行元素测定的两种方法。试验证明用硫磷混合酸发烟消解法测定低合金钢中多元素具有较高的灵敏度和精密度,方法的线性相关系数较好,相对标准偏差小于1.8%。与高氯酸法发烟消解法比较,硫酸磷酸混合酸发烟消解法具有操作简单,所需试剂较少,结果稳定等特点。     

Treatment of complex silver arsenide concentrate in nitric acid system

A complex silver arsenide-sulphide concentrate containing bismuth, cobalt, nickel, copper, zinc, lead and iron as major constituents, was leached in nitric acid. The leach solution, which contained 95% to 99% of the Ag, Bi, Co, Ni, Cu, As and Fe present in the ore, was further processed to separate the metals into the following fractions: (1) silver chloride, (2) bismuth oxychloride and/or hydroxide, (3) arsenic-iron precipitate and (4) Ni-Co-Cu-Zn sulphide. Silver was precipitated from solution with sodium chloride. Bismuth oxychloride-hydroxide and arsenic-iron were precipitated by controlled ammonia addition and cobalt-nickel-copper-zinc sulphides were precipitated with ammonium sulphide. Silver chloride was further processed to a high purity silver powder by heat treatment with sodium carbonate. The parameters controlling each processing step are discussed.     

Recovery of plutonium from non-irradiated refractory plutonium and uranium-plutonium oxides,nitrides and carbides

In the recovery of plutonium from high-fired uranium-plutonium oxides dissolution is the most critical step. It has been found that 100% solid solutions of uranium-plutonium oxides are readily soluble in 14 m nitric acid. A procedure has been developed to convert any mixed oxide completely into a solid solution, so that dissolution is faster than the usual direct dissolution in nitric acid-hydrofluoric acid. The use of the latter acid is thus avoided. Nitrides and carbides are oxidised to oxides which are subsequently dissolved in pure concentrated nitric acid. Detailed procedures are given.     

高纯,超细SrTiO3中钛锶比的测定

将化学沉淀法制备的ＳｒＴｉＯ３溶于硫酸，加入有Ｈ２Ｏ２存在的４０％乙醇溶液中，加入过量ＥＤＴＡ标准溶液，ＴｉＯ＾２＋形成Ｔｉ－Ｈ２Ｏ２－ＥＤＴＡ络合物，Ｓｒ＾２＋沉淀为ＳｒＳＯ４。钛、锶分离后，用重法测定锶的含量，用Ｃｕ＾２＋离子标准溶液回滴过量ＥＤＴＡ，测定钛的含量。     

湿法磷酸副产氟硅酸制备冰晶石的降硅试验探讨

分析了用湿法磷酸副产的氟硅酸直接加铝盐和钠盐反应得到的氟化铝溶液与氟化钠颗粒合成高分子比冰晶石时,产品中二氧化硅含量超标的原因。对氟化铝溶液中的二氧化硅颗粒和氟硅酸根2种物质用不同方法进行分离比较,结果表明硫酸钠可用于降低氟硅酸根,且用降硅后的氟化铝溶液可以制备出符合国家标准要求的高分子比冰晶石。