2,4-二羟基苯甲酸在3种树脂上的吸附特性

通过静态和动态吸附实验, 研究了717(凝胶型,强碱)、D201(大孔型,强碱)和D301R(大孔型,弱碱)3种阴离子交换树脂对水溶液中2,4-二羟基苯甲酸的吸附特性. 结果表明,717和D201在pH 4~11时、D301R在pH 3~9时吸附能力最好. 在pH=5及温度293~313 K、初始浓度0.6488~6.488 mmol/L条件下,D301R, 717和D201对2,4-二羟基苯甲酸的等温吸附规律均符合Freundlich模型,最大平衡吸附量分别为2.98, 2.66和2.54 mmol/g(吸附未达饱和),均为物理性自发吸附的放热过程. 动力学实验数据用准一级模型方程拟合比准二级更接近实验值. 5%(w) NaCl+2%(w) NaOH脱附液100 mL均可有效洗脱3种树脂上吸附的2,4-二羟基苯甲酸,脱附率达99%. 相同条件下,D301R树脂对2,4-二羟基苯甲酸的吸附性能优于D201和717树脂.     

乙醛酸/草酸混合溶液吸附分离特性研究

以乙醛酸/草酸混合溶液的吸附分离为对象,采用弱碱性树脂D301R、D301G、D392为吸附剂,考察了3种树脂在常温下对乙醛酸、草酸的单组分体系和双组分体系的等温吸附平衡,研究了相比对分离效果的影响.实验结果表明,3种树脂中D301G的饱和吸附量最大,比较适合双组分吸附分离;以乙醛酸纯度和收率衡量吸附分离效果,3种树脂的分离效果为D301G≈D301R＞D392.树脂官能团化学计量不足可以有效地提高分离效率.     

苦味酸和2,4-二硝基酚在弱碱性树脂上的等温吸附

采用静态法研究了水溶液中苦味酸和2,4-二硝基酚在D301R树脂上的吸附平衡,考察了树脂用量、温度、质量浓度等对吸附的影响,探讨了等温吸附特性。结果表明:单溶质吸附体系中,苦味酸或2,4-二硝基酚的吸附量随树脂用量的增大呈下降趋势,随溶液温度的升高而升高,吸附均为吸热过程。在平衡质量浓度1—350 mg/L范围内的等温吸附符合Freundlich模型。但在双溶质吸附体系中,苦味酸的吸附量随树脂用量的增大出现极大值现象,2,4-二硝基酚的变化趋势与单溶质时相似。双溶质吸附等温线表明,2,4-二硝基酚的吸附等温线出现拐点,随后吸附量急剧上升;苦味酸的吸附等温线则出现极大值,随后吸附量有所下降,与单溶质体系的吸附等温线不同。树脂对苦味酸和2,4-二硝基酚双溶质的吸附均呈现了不同程度的竞争吸附效应。     

弱碱性阴离子交换树脂对于废水中锑吸附效果的研究

通过实验法研究了D301R树脂在不同初始pH值及不同阴离子的条件下对Sb(Ⅲ)和Sb(Ⅴ)的吸附量,并进行了吸附动力学分析。结果表明:D301R树脂对Sb(Ⅲ)和Sb(Ⅴ)的吸附量随pH值的增加逐渐减小;NO_3~-、SO_4~(2-)、Cl~-、PO_4~(3-)等竞争性阴离子对Sb(Ⅲ)吸附结果影响不大,但SO_4~(2-)、PO_4~(3-)可以与Sb(OH)_6~-竞争吸附位点从而降低对Sb(Ⅴ)吸附量。动力学研究表明,Sb(Ⅲ)和Sb(Ⅴ)均在24 h内达到吸附平衡;Sb(Ⅲ)和Sb(Ⅴ)的吸附均为自发吸热,吸附情况更趋于单分子层吸附。     

大孔树脂对刺五加中总黄酮吸附研究

通过比较5种不同极性的大孔树脂对刺五加中总黄酮的吸附性能,筛选出吸附效果最佳的树脂,对其进行静态吸附研究。并进一步通过吸附过程的热力学和动力学研究其吸附规律。结果表明,D301R树脂吸附效果最好,在25℃、5 h、固液比为3:40的条件下,吸附量能达到56.89 mg/g。根据动力学结果,其吸附过程更符合准二级动力学。通过采用Freundlich和Langmuir等温吸附方程进行拟合不同温度下D301R大孔树脂对刺五加中总黄酮的吸附过程,Langmuir等温吸附模型拟合度更高,说明该吸附为单分子吸附。     

大孔树脂复配纯化油茶多酚的吸附特性研究

为提高大孔吸附树脂对油茶多酚的吸附性能,采用不同极性的大孔树脂复配的方法,对油茶籽饼粕中提取的多酚物质进行吸附纯化。研究表明,90%(wt)D101-1/10%(wt)DM301复配对油茶多酚的吸附效率最高、达83.75%,且高于单一树脂对油茶多酚的吸附。在温度为298~315 K,三种模型的非线性拟合结果表明复配树脂对油茶多酚吸附平衡数据符合Langmuir等温吸附模型;对吸附焓、自由能、吸附熵的计算进一步验证了复配树脂对油茶多酚的吸附是放热自发的物理吸附。在此基础上进一步研究了298 K下复配树脂对油茶多酚的吸附动力学,结果表明Pseudo-second-order动力学模型能够很好地描述该吸附过程。     

D301树脂的胺基化改性及其对AuCl4-的吸附性能

以D301树脂表面的胺基与过硫酸铵构成氧化-还原引发体系,将单体甲基丙烯酸缩水甘油酯(GMA)接枝聚合到D301树脂表面,制得接枝材料D301-g-PGMA;通过聚甲基丙烯酸缩水甘油酯(PGMA)分子链上的环氧基团与乙二胺中胺基的开环反应,实现接枝材料的胺基化改性,制得吸附材料D301-g-APGMA,考察了接枝聚合条件对接枝率的影响及胺基化反应条件对胺基含量的影响,对材料的结构进行了表征,研究了其对AuCl4-的吸附性能. 结果表明,在GMA用量10 mL、过硫酸铵为单体质量的1.5%及40℃条件下反应18 h, PGMA接枝率达41.15%. 胺基化改性时,在90℃下反应8 h,D301-g-PGMA上环氧键的开环率达91.67%. 改性后D301-g-APGMA对AuCl4-的吸附能力比D301树脂有较大提升,吸附容量达276.74 mg/g. D301-g-APGMA具有良好的再生与重复使用性能.     

梨多酚在大孔树脂上的吸附性能研究

主要考察大孔树脂对梨多酚的吸附性能,通过静态吸附解吸实验筛选吸附梨多酚的最佳树脂,并利用筛选的树脂进行吸附动力学和吸附等温线研究。实验结果表明,HPD-500和D101树脂具有最好的吸附能力;HPD-500和D101树脂对梨多酚的吸附均在90min左右可达到吸附平衡,吸附过程符合准二级动力学方程;Freundlich吸附等温模型能较好地描述梨多酚在HPD-500和D101树脂上的吸附行为;50%乙醇可用作解吸溶剂。     

H2O2-V2O5催化氧化再生吸附树脂的机理及动力学

利用红外光谱及紫外光谱初步分析了H2O2-V2O5催化氧化再生D301吸附树脂的机理,同时对其反应动力学进行了探讨.结果表明:随着氧化反应的进行,D301吸附树脂上活性深蓝K-R的特征峰逐渐减弱,当反应进行40 min时,活性深蓝K-R的特征峰几乎消失.D301吸附树脂在经过6次再生之后,树脂本身的一些基团可能受到一定...     

弱碱性树脂处理β-萘磺酸废水的吸附分离热力学性能

研究了β-萘磺酸废水中β-萘磺酸、H₂SO₄、H₂SO₃ 单组分吸附平衡,并以Langmuir、Freundlich模型对其进行模拟.吸附过程的热力学计算及分析结果表明,吸附过程为放热的化学吸附过程,吸附量顺序为H₂SO₄>NSA>H₂SO₃,推动力大小顺序为H₂SO₄>NSA>H₂SO₃,吸附过程熵增加.以D301R弱碱性树脂为吸附剂,可有效地实现三者的分离.     

以弱碱性树脂去除废水中5-氨基-2-氯苯-4-磺酸和盐酸

This research deals with an investigation of the adsorption of two acids, namely, 5-amino- 2-chlorotoluene-4-sulfonic and chlorhydric acids from their solution onto weakly basic resin. The screening of resins, kinetics, and isotherm were studied. The results indicate that the D301R is more appropriate for the removal of acids from solution. The adsorption of acids obeys Langmuir isotherm and the first-order kinetics model. Sorptive affinity of the two acids on D301R was found to be in the order of 5-amino-2-chlorotoluene-4-sulfonic acid〉 chlorhydric acid. Thermodynamic parameters for the adsorption of acids were calculated and discussed. The maximum removal of acids was observed around 97% and 76% at 25℃ for 5-amino-2-chlorotoluene-4-sulfonic acid and chlorhydric acid, respectively.     

改性活性炭对甲基橙的吸附

用盐酸和氨水对活性炭进行改性获得改性活性炭,将其用于处理甲基橙废水,考察了改性条件、振荡速度和温度等因素对甲基橙吸附性能的影响,采用吸附等温模型和吸附动力学模型进行拟合,并分析吸附过程的热力学特征. 结果表明,盐酸改性活性炭对甲基橙的吸附效果优于氨水改性活性炭,在甲基橙初始浓度60 mg/L、溶液体积50 mL、温度20℃、振荡速度100 r/min、盐酸改性活性炭投加量0.2 g时,24 h基本达到吸附平衡,甲基橙去除率为93.7%. 不同温度下,盐酸改性活性炭对甲基橙的吸附符合Langmuir(RC2>0.95)和Freundlich(RC2>0.97)吸附等温模型,饱和吸附量达112.7 mg/g. 热力学参数DG0<0,DH0>0,DS0>0,表明盐酸改性活性炭对甲基橙的吸附是自发吸热反应,其吸附动力学可用准二级动力学方程描述,随振荡速度增加,吸附速率常数增加.     

1-氨基-4=对甲基苯磺酰胺-9,10-蒽醌-2=磺酸的合成工艺研究

介绍了以溴氨酸与对甲苯磺酰胺为原料,以水为溶剂,碳酸钠为缚酸剂,硫酸铜为催化剂,采用酸析方式可以得到高纯度的1-氨基-4-对甲基苯磺酰胺-9,10-蒽醌-2-磺酸的合成工艺。收率可达95%,产品纯度大于99%。     

Inhibition of mild steel corrosion in sulfuric acid solution by thiadiazoles

Four heterocyclic compounds namely 2-amino-1,3,4-thiadiazoles (AT), 5-Methyl-2-amino-1,3,4-thiadiazoles (MAT), 5-Ethyl-2-amino-1,3,4-thiadiazoles (EAT) and 5-Propyl-2-amino-1,3,4-thiadiazoles (PAT) were synthesized and their influence on the inhibition of corrosion of mild steel (MS) in 0.5 M H₂S0₄ was investigated by weight loss and potentiodynamic polarization techniques. The values of activation energy, free energy of adsorption, heat of adsorption, enthalpy of activation and entropy of activation were also calculated to investigate the mechanism of corrosion inhibition. Potentiodynamic polarization studies were carried out at room temperature, and showed that all the compounds studied are mixed type inhibitors causing blocking of active sites on the metal. The inhibition efficiency of the compounds was found to vary with concentration, temperature and immersion time. Good inhibition efficiency was evidenced in the sulfuric acid solution. The adsorption of the compounds on mild steel for sulfuric acid was found to obey Langmuir’s adsorption isotherm. FT–IR spectroscopic studies were also used to investigate the purity of compounds synthesized.     

Fatty acid triazoles: Novel corrosion inhibitors for oil well steel (N-80) and mild steel

Three fatty acid triazoles, namely, 3-undecane-4-aryl-5-mercapto-1,2,4-triazole (triazole 1), 3(heptadeca-8-ene)-4-aryl-5-mercapto-1,2,4-triazole (triazole 2), and 3(deca-9-ene)-4-aryl-5-mercapto-1,2-4-triazole (triazole 3) were synthesized and their corrosion-inhibiting action in 15% hydrochloric acid was evaluated by weight-loss method and electrochemical techniques. Electrochemical polarization studies at room temperature indicated that all the triazoles are mixed-type inhibitors, i.e., they inhibit both anodic and cathodic reactions. The adsorption of these compounds onto mild steel from 15% HCl followed Temkin's adsorption isotherm.     

Inhibition of mild steel corrosion in the presence of fatty acid triazoles

The influence of some fatty acid triazoles namely, 4-Phenyl-5-undecyl-4H- [1,2,4] triazole-3-thiol (PUTT), 5-Heptadec-8-enyl-4-phenyl-4H- [1,2,4] triazole-3-thiol (HPTT), and 5-Dec-9-enyl-4-phenyl-4H- [1,2,4] triazole-3-thiol (DPTT) on the corrosion of mild steel in 1 M hydrochloric acid (HCl) and 0.5 M sulfuric acid (H₂SO₄) was studied by weight loss and potentiodynamic polarization methods. The values of activation energy and free energy of adsorption of all the triazoles were calculated to investigate the mechanism of corrosion inhibition. The potentiodynamic polarization studies were carried out at room temperature, according to which all the compounds were mixed type inhibitors and inhibit the corrosion of mild steel by blocking the active sites of the metal. The adsorption of all the triazoles on mild steel surface in both the acid solutions was found to obey the Langmuir adsorption isotherm. All the compounds showed good inhibition efficiency in both acids. The inhibition efficiency of the compounds was found to vary with their nature and concentration, solution temperature and immersion time. Electrochemical impedance spectroscopy was also used to investigate the mechanism of the corrosion inhibition.     

磺酸萘在超临界水中氧化降解路径的研究

采用GC-MS对1-氨基-2-羟基-4-磺酸萘有机污染物在超临界水中氧化降解的产物进行了分析和鉴别,通过对中间产物的鉴别和结合相关研究提出了其在超临界水中氧化降解的路径。1-氨基-2-羟基-4-磺酸萘氧化降解的路径可用纵横交叉模式描述,即纵向的氧化开环降解反应和横向的耦合反应,该污染物及其带芳环中间产物进一步氧化都经过苯酚,并由其继续开环氧化降解。     

O,O’-二(环己基)二硫代磷酸-N,N,N-三乙铵的制备及缓蚀性能研究

制备了酸洗有机缓蚀剂O,O’-二(环己基)二硫代磷酸-N,N,N-三乙铵(NTOD),采用失重法、电化学法研究了NTOD在5%HCl溶液中对Q235钢的缓蚀性能和吸附行为。研究结果表明:NTOD在5%HCl溶液中是一种混合型缓蚀剂,在5%HCl溶液中的最高缓蚀率达到97%;NTOD在Q235钢表面的吸附完全符合Langmuir吸附等温式,属化学吸附。同时,还研究了腐蚀体系温度、酸浓度、放置时间对NTOD缓蚀性能的影响。     

不对称金属络合染料C.I.酸性棕355的合成

6-硝基-1,2-重氮氧基萘-4-磺酸与乙萘酚偶合,得偶合物I;2-氨基-4-硝基苯酚-6-磺酸重氮化与1-苯基-3-甲基-5-吡唑啉酮偶合,得到偶合物II;偶合物I与铬明矾在水杨酸存在下络合,得到单络合物III;络合物III再与偶合物II在碱性条件下络合,得到不对称金属络合染料C.I.酸性棕355。     

TiO2 Immobilized on Manihot Carbon: Optimal Preparation and Evaluation of Its Activity in the Decomposition of Indigo Carmine

Applications of carbon-TiO₂ materials have attracted attention in nanotechnology due to their synergic effects. We report the immobilization of TiO₂ on carbon prepared from residues of the plant Manihot, commercial TiO₂ and glycerol. The objective was to obtain a moderate loading of the anatase phase by preserving the carbonaceous external surface and micropores of the composite. Two preparation methods were compared, including mixing dry precursors and immobilization using a glycerol slurry. The evaluation of the micropore blocking was performed using nitrogen adsorption isotherms. The results indicated that it was possible to use Manihot residues and glycerol to prepare an anatase-containing material with a basic surface and a significant S_BET value. The activities of the prepared materials were tested in a decomposition assay of indigo carmine. The TiO₂/carbon eliminated nearly 100% of the dye under UV irradiation using the optimal conditions found by a Taguchi L4 orthogonal array considering the specific surface, temperature and initial concentration. The reaction was monitored by UV-Vis spectrophotometry and LC-ESI-(Qq)-TOF-MS, enabling the identification of some intermediates. No isatin-5-sulfonic acid was detected after a 60 min photocatalytic reaction, and three sulfonated aromatic amines, including 4-amino-3-hydroxybenzenesulfonic acid, 2-(2-amino-5-sulfophenyl)-2-oxoacetic acid and 2-amino-5-sulfobenzoic acid, were present in the reaction mixture.