煤燃烧脱硫过程中含硫阴离子色谱分析

建立了煤燃烧脱硫过程中主要含硫阴离子及常见无机阴离子的快速离子交换色谱分离和定量方法。以0.8mmol/L邻苯二甲酸氢钾作流动相，非抑制型电导检测法检测SO3^2-和SO4^2-的下限浓度分别为0.5mg/L和1.0mg/L。所建立的分析方法被用于脱硫方法的研究。同时，验证了甲醛溶液作为SO3^2-保护剂的机理是甲醛与SO3^2-形成了稳定的配合物。     

离子色谱法测定生活饮用水中4种阴离子

对离子色谱法测定饮用水中的F-,C1-,NO3- -N,SO4^2--4种阴离子的分析方法进行了优化。用正交试验法选择最优实验条件为：流速0．9mL／min,柱温32℃。4种阴离子检出限：F-0．02mg／L,Cl-0．04mg／L,NO3--N0．04mg／L,SO4^2- 0．16mg／L。测定结果相对标准偏差均小于5％,回收率为91.3％～106．1％,相关系数大于0．999。该方法操作简便,灵敏度、准确度高,标准工作曲线线性良好,可用于饮用水中F-,C1-,NO3^- —N,SO4^2—4种离子的同时分析。     

离子色谱法测定烟气脱硫海水中的亚硫酸根离子

建立了燃煤电厂烟气脱硫海水中亚硫酸根(SO2~3)的离子色谱-脉冲安培检测方法。色谱柱为IonPac AS14A阴离子交换柱,流动相为14 mmol/L NaOH-12 mmol/L Na2CO3溶液(pH 11.7),流速1.2 mL/min,脉冲安培法检测。因SO2~3易被氧化,故在采样时加入甲醛作为保护剂,使之稳定存在。在测定海水样品前,用NaOH溶液(pH 12.0)沉淀海水中的Mg2+,以避免其在pH较高的流动相中生成沉淀堵塞色谱柱。采用该方法检测SO2~3的线性范围为0～100 mg/L,平均回收率为116.8%,检出限为0.05 mg/L;对7.5,25.0和75.0 mg/L的海水基底加标溶液分别进行9次平行测定,其相对标准偏差(RSD)分别为2.1%,3.1%和4.0%。该方法具有快速、灵敏、选择性好等特点,用于烟气脱硫的海水中SO2~3的检测,可得到令人满意的结果。     

离子缔合物-萃取荧光光度法测定水中阴离子表面活性剂

在 0 .2 5 mol/L H2 SO4 溶液中 ,罗丹明 B与阴离子表面活性剂形成离子缔合物 ,氯仿萃取后 ,于 5 5 0 nm处激发 ,荧光波长为 60 0 nm,对于十二烷基硫酸钠的线性范围为 0 .0 2 5～ 0 .4mg/L,RSD<2 .6%。方法可用于河水及生活废水中 1 0 -7～ 1 0 -6mol/L 阴离子表面活性剂的测定     

离子色谱法测定米酒中NO-3和NO-2

研究了用带电导检测器的离子色谱对米酒中阴离子NO3^-、NO2^－进行分离测定的方法。NO3^-、NO2^－的线性范围分别为0．5－80mg/L和0.1-20mg/L，检出限分别为0.5mg/L和0.1mg/L。该法适用于SO4^2-、CI^-的测定。     

萃取分离-离子色谱法测定间羟基-N,N-二乙基苯胺中的无机阴离子

建立了检测常用化工原料间羟基-N,N-二乙基苯胺中无机阴离子(F-、Cl-、NO3-和SO42-)含量的萃取分离-离子色谱分析方法。方法以甲苯为溶剂溶解间羟基-N,N-二乙基苯胺,用水相萃取分离得到其中的无机阴离子F-、Cl-、NO3-和SO42-等;色谱柱采用Metrosep A supp 5型阴离子分离柱,流动相为3.2 mmol/L Na2CO3与1.0 mmol/L NaHCO3的混合液,流速0.7 mL/min。结果表明:F-、Cl-、NO3-和SO42-的线性关系分别为y=1.2036x 1.0703(r=0.9999)、y=1.3999x-0.2531(r=0.9999)、y=2.6612x-0.9482(r=1.0000)、y=1.9337x 0.0719(r=0.9999);平均回收率分别为F-101.6%(RSD 5.92%),Cl-107.6%(RSD 4.82%),NO3-106.9%(RSD 3.08%),SO42-95.17%(RSD 3.32%);检出限分别为:F-0.003 mg/L、Cl-0.005 mg/L、NO3-0.016 mg/L和SO42-0.010 mg/L。该方法简便、快速、灵敏度高,具有较强的实用价值。     

离子色谱法同时测定土壤中Cl-、SO42-和 NO3-

利用离子色谱法同时测定土壤中的Cl^-、SO4^2-、NO3^-三种无机阴离子。采用30 mmol/L KOH淋洗液在1.2 mL/min流速下对Cl^-、SO4^2-、NO3^-三种无机阴离子进行分离测定,混合标准溶液的相对标准偏差为0.16%~0.84%,三种阴离子的线性范围都在0~150 mg/L,线性相关系数均大于0.999。三种阴离子的检出限分别是0.062、0.096和0.064 mg/L。对四种国家标准物质的测定结果表明(n=9),测定值与标准值一致,相对标准偏差(RSD)<3%,三种阴离子的加标回收率为95.6%~109%。采用离子色谱法测定土壤中的Cl^-、SO4^2-、NO3^-三种无机阴离子,方法简便、快捷、无污染,对人体无任何伤害,真正实现了绿色化学的分析要求。在6 min以内完成分析,适合大批量土壤水溶盐阴离子的测定。     

阴离子交换色谱法测定硫磺熏制姜中亚硫酸盐

建立了阴离子交换色谱分离、抑制型电导检测分析硫磺熏制生姜(简称硫磺姜)中亚硫酸盐的方法。使用NJ-SA-4A阴离子交换分析柱,淋洗液为1.92mmol/L Na2CO3-1.80mmol/L NaHCO3-2%(体积分数)丙酮。通过在样品提取液中加入三乙醇胺,有效地维持了亚硫酸盐的稳定性、并能提高方法的选择性。SO23-在0.02～2.00mg/L范围内线性良好,相关系数为0.9998,峰面积的相对标准偏差为1.9%。方法的检出限为0.015mg/L,加标回收率为84.0%～93.5%。该方法为生姜的市场监测提供了有效的方法。     

催化动力学光度法测定阴离子表面活性剂

基于在H2SO4介质中,阴离子表面活性剂对高碘酸钠氧化罗丹明B褪色的反应具有较强的催化作用,建立了测定阴离子表面活性剂的催化动力学光度法.本文以十二烷基硫酸钠为标准品进行实验,线性范围为0.08～0.20 mg/L,检出限为0.0193 mg/L.用于水样中阴离子表面活性剂总量的测定,测定结果的相对标准偏差为1.3%～1.4%,回收率为104%～106%.     

离子色谱法测定柠檬酸、柠檬酸钠中的F^—、CI^—、SO4^2—、C2O4^2—等

利用离子色谱仪,对柠檬酸、柠檬酸钠中的痕量F^-、CI^-、SO4^2－、C2O4^2-等进行测定,采用DIONEX ION PAC AS11－HC分离柱,以电导检测器检测,对淋洗分离条件进行了试验。选择NaOH作淋洗液,0．025－0．050mol/L NaOH做梯度淋洗,可使F^-、CI^-、SO4^2－、C2O4^2-等很好地分离,其中CI^-在0．01－200mg/L,F^-在0．05－200mg/L,SO4^2-在0.05-200mg/L,C2O4^2-在0.1-200mg/L范围内,浓度和响应值有良好的线性关系,检出限分别为F^-0.01mg/L、CI^-0.01mg/L、SO4^2-0.03mg/L、C2O4^2-0.03mg/L,回收率为90％－110％。该方法无需前处理,无基体干扰,可用于柠檬酸、柠檬酸钠中F^-、CI^-、SO4^2－、C2O4^2-的测定。     

流动注射催化动力学光度法测定碘离子

Based on catalysis of I- on the decolor reaction between potassium bromate and indigo carmine in the acid medium,and combined with flow injection analysis,a new flow-injection catalytic kinetic spectrophotometric method was found for determination of iodide in sample.The experimental results show that the determination is carried out at temperature of 80℃ and the concentration of H_2SO_4,KBrO_3,and indigo carmine is 1.2 mol/L,1.8×10~(-2) mol/L and 1.0×10~(-4) mol/L respectively,the linear range for the method is 0.50～1.8 mg/L.The detection limit is 0.0022 mg/L.The relative standard deviation is 1.92%.The proposed method was applied to the determination of iodide in troche successfully.The recovery was between 99.2% and 103.6%.     

纳米金修饰玻碳电极对甲醛的电催化氧化

利用电沉积方法制备了纳米金(nano-gold,NG)修饰玻碳电极(GCE)。在碱性介质中该电极对甲醛有较好的催化氧化作用,使甲醛在0.65 V左右出现一个氧化峰,依此测定甲醛的含量。通过实验确定了纳米金的沉积电位和沉积时间,以及纳米金对甲醛的催化氧化所需的底液。该法测定甲醛的线性范围为1~1 000μg/L,检出限为0.3 mg/L。加标回收率为98.5%~101.8%。     

Synthesis of Ethyl Oleate Catalyzed by Solid Superacid SO4^2-/TiO2/La3＋

Rare-earth compound solid superacid SO42-/TiO2/La3+ was prepared. Its catalytic activity was examined under different synthetic conditions for the esterification of propanoic acid and n-butyl alcohol as probing reaction. The optimum conditions were also found, which were the pH=8, the depositing time was 24 h, the mass fraction of La(NO3)3 used in solid superacid was 5%, the concentration of H2SO4 was 1.25 mol/L, the soaking time in H2SO4 was 16 h and the calcining temperature was 500 °C. The ethyl oleate was synthesized from oleic acid and ethanol in the presence of SO42-/TiO2/La3+. The optimum reaction conditions were obtained which were the reaction time was 6 h, molar ratio of oleic acid to ethanol was 1:4 and the mass fraction of catalyst was 4%.     

铂微粒修饰的聚苯胺薄膜电极对甲醛氧化的电催化作用

以电位扫描法把铂微粒沉积在聚苯胺（ＰＡｎ）薄膜是上以制得铂微粒修饰的聚苯胺薄膜电极。该电极的催化活性以甲醛在０．５ｍｏｌ／Ｌ硫酸溶液中的电化学氧化测定。它集催化活性和电活性于一体，对甲醛在酸性介质中的电化学氧化显示了非常高的电催化活性。较之裸铂电极，ＰＡｎ薄膜电极，其催化电流提高１０倍。铂微粒的大小，分布和载量，甲醛的浓度，基体金属的种类等因素对电极材料的催化活性均有影响。     

食品包装材料与容器涂料中甲醛的示波极谱测定方法的研究

在ｐＨ５．０的０．０２ｍｏｌ／Ｌ乙酸－乙酸钠介质中,甲醛与硫酸肼的反应产物在－１．０４Ｖ处产生一个灵敏的吸附还原波,其峰高（ｉｐ）与甲醛浓度在０．０１～１．０ｍｇ／Ｌ范围内呈良好的线性关系。方法操作简便、快速、灵敏、选择性好。用于食品包装材料、容器内壁涂料中游离甲醛的测定,均获得与国标法一致的效果。     

The effectiveness of bisulfite-activated permanganate technology to enhance the coagulation efficiency of Microcystis aeruginosa

The effects of bisulfite-activated permanganate technology(PM/BS) as a pre-oxidation process on enhancing Microcystis aeruginosa(M.aeruginosa) removal by post coagulation were investigated.The results demonstrated that pretreatment with PM/BS process effectively promoted the algae removal by coagulation with Al_2(SO_4)_3 as the coagulant and this phenomenon was more obvious with the increase of water hardness.Compared to the sole coagulation,PM/BS pre-oxidation combing with coagulation could neutralize the zeta potential of algal cells effectively,decrease the algal cell size,and lead to the formation of more compact flocs due to the in-situ generated Mn02.The effect of oxidant dosages on algal organic matter(AOM) was also studied and no obvious release of macromolecular substances was observed with the dosage of KMn04 increasing from 3.0 mg/L to 7.0 mg/L,suggesting the integrity of algal cells at a high KMn04 dosage.Moreover,PM/BS pre-oxidation could lead to the decrease of most analyzed disinfection by-products(DBPs) at a Al_2(SO_4)_3 dosage of 40.0 mg/L.The algae removal efficiency was also significantly enhanced by PM/BS pre-oxidation in the test using real algae-laden water.This study indicated that PM/BS process might be a potential assistant technology for algae removal by subsequent coagulation.     

催化发光法同时测定空气中的甲醛、苯和二氧化硫

基于甲醛、苯和二氧化硫在纳米Ti3CeY2O11上的催化发光有交叉敏感现象,在3个波长处分别确定甲醛、苯和二氧化硫浓度与催化发光信号强度的响应关系,再依据发光信号强度的叠加性特征即可获取甲醛、苯和二氧化硫的准确浓度,据此建立了同时测定空气中甲醛、苯和二氧化硫的新方法.3个分析波长分别为420、535和680 nm,敏感材料表面温度为280℃,载气流速为130 mL/min.本方法对甲醛、苯和二氧化硫的检出限(3σ)分别为0.04、0.05和0.10 mg/m3,线性范围分别为0.08~75.60 mg/m3、0.10~101.40 mg/m3和0.30~115.00 mg/m3, 回收率分别为96.4%~103.7%、97.8%~102.5%和97.2%~103.3%.常见共存物,如乙醛、甲苯、硫化氢、氨、甲醇、乙醇和二氧化碳等不干扰测定.连续200 h通浓度均为50 mg/m3的甲醛、苯和二氧化硫混合气体,发光强度的相对偏差≤2%,表明此纳米级复合氧化物对甲醛、苯和二氧化硫的敏感性的寿命长.本方法充分利用了交叉敏感现象,可以实现空气中甲醛、苯和二氧化硫的在线分析.     

Sequential spectrophotometric determination of methanol and iron in vinegar by a flow injection-pervaporation method

An easily automatable sequential flow-injection-pervaporation method is proposed for the photometric determination of methanol and iron in vinegar. The method is based on separation of the methanol from the sample matrix by pervaporation followed by its oxidation to formaldehyde with permanganate, decolouration of the latter with S(2)O(5)(2-), and subsequent reaction of formaldehyde with p-rosaniline to yield a violet reaction product with maximum absorption at 567 nm. Iron is determined by an existing method based on reaction with thiocyanate in acidic medium and monitoring at 508 nm. After optimisation by either the univariate or multivariate approaches, as required, the linear range was established for methanol (4-1000 mg L(-1)) and iron (0.18-20 mg L(-1)). The proposed method was then compared with reference methods for methanol and iron in terms of repeatability (2.452 mg L(-1) and 0.245 mg L(-1), respectively), reproducibility (4.435 mg L(-1) and 0.356 mg L(-1), respectively), detection limit (LOD=82 and 0.234 mg L(-1), respectively), and traceability. The throughput was nine samples per hour.     

天青A-溴酸钾体系催化光度法测定微量甲醛

研究了在H2SO4介质中,微量甲醛对KBrO3氧化天青A有较强的催化作用,建立了催化光度法测定微量甲醛的新方法.方法的线性范围为0.035～0.66 mg/L,检出限为0.016 mg/L.该方法用于米粉、粉丝等食品中甲醛的测定,测定结果的相对标准偏差(RSD)小于5%,加标回收率为98.5%～101.2%.     

木质素阳离子絮凝剂的合成及其絮凝性能研究

以酶解木质素、甲醛、二甲胺及阳离子化试剂为原料,制备了木质素基阳离子絮凝剂.改变阳离子化试剂的用量、缩合反应的温度和时间等因素,制备不同阳离子度的木质素阳离子絮凝剂;通过其对酸性黑10B的脱色效果研究,确定了最优的制备方案.利用最优条件制备的木质素阳离子絮凝剂对三种不同种类阴离子染料废水进行了絮凝脱色处理.结果表明,原...