应用离子交换树脂生产高纯度的癸二酸

介绍应用离子交换树脂工艺生产含铁量在PPM级的癸二酸。     

D354大孔弱碱树脂吸附游离酸的行为研究

利用电导实验技术,跟踪观察D354大孔弱碱离子交换树脂吸附游离酸的行为。利用固—液界面吸附的动力学方程,求取吸附过程吸附质亲和能。讨论酸的浓度和树脂类型对吸附行为的影响。     

离子交换树脂非均相催化乙酰化合成乙酰甲胺磷

研究了在间易搅拌釜中以阳离子交换树脂为催化剂，由甲胺磷催化乙酰化合成乙酰甲胺磷。分别考察了不同类型离子交换树脂的催化乙酰化作用。并且研究了搅拌速度，催化剂用量以及反应温度对乙酰化反应的影响。研究结果表明，以NKC9型离子交换树脂在333.15K温度下具有最好的催化乙酰化作用。     

处理条件对丙烯酸树脂交换容量和强度的影响

研究了温度、酸碱处理对弱碱性丙烯酸树脂交换容量和强度的影响。50℃热水浸泡和1mol/L酸碱周期处理使得一类弱碱性丙烯酸树脂交换容量较快下降,下降约8%后,有明显转折点,下降平缓;使得另一类丙烯酸树脂交换容量逐步下降,无明显转折点,但总体下降趋势越来越小。50℃热水浸泡对丙烯酸树脂强度影响很小,下降约2%后,下降平缓;1mol/L酸碱周期处理使得丙烯酸树脂强度越来越小。     

钠盐浓度对厌氧产氢颗粒污泥从蔗糖中产氢的影响

This work evaluated the effects of sodium ion concentration, ranging from 0 to 16000mg·L-1(Na ), on the conversion of sucrose to hydrogen by a high-activity anaerobic hydrogen-producing granular sludge. At the optimum sodium ion concentration [1000-2000mg·L-1(Na )] for hydrogen production at 37℃, the maximum sucrose degradation rate, the specific hydrogen production yield and the specific hydrogen production rate were 393.6-413.1mg·L-1·h-1, 28.04-28.97ml·g-1, 7.52-7.83ml·g-1·h-1, respectively. The specific production yields of propionate, butyrate and valerate decreased, with increasing sodium ion concentration, whereas the specific acetate production yield increased, meanwhile the specific production yields of ethanol and caproate were less than 55.3 and 12.6mg·g-1, respectively. The hybrid fermentation composition gradually developed from acetate, propionate and butyrate to acetate with the increase in sodium ion concentration.     

强酸性阳离子交换树脂催化合成马来酸双丁酯

利用强酸性阳离子交换树脂催化马来酸酐和正丁醇制备马来酸双丁酯,当马来酸酐与正丁醇的摩尔比为 ０１∶０６,树脂用量 １２５ ｇ,反应温度 １２０～１２４ ℃,反应时间 １４０ ｍ ｉｎ 时,酯收率大于 ９０ ％ 。     

树脂固载硅钨酸催化合成乙二醇硬脂酸酯

以树脂固载硅钨酸为催化剂,乙二醇和硬脂酸为原料,催化合成乙二醇硬脂酸酯。重点研究离子交换树脂的种类、催化剂用量、反应时间、带水剂的种类及其用量,醇酸摩尔比等因素对合成乙二醇硬脂酸酯收率的影响。结果表明,催化剂用量为硬脂酸质量的25％,反应时间为4.5h,n乙二醇：n硬脂酸=3.0：1,环己烷带水剂量为10mL,酸的转化率可达94％以上,并且催化剂可以重复使用。     

污泥厌氧发酵产酸机理及应用研究进展

为了实现污水中污泥减量化和资源化,对其进行厌氧消化是目前国际上应用最广泛的处理方法。酸化阶段的重要产物——挥发性脂肪酸（VFAs）不仅可以作为污水脱氮除磷的碳源,还是合成生物质塑料聚羟基脂肪酸酯（PHAs）的理想底物。简单介绍了污泥厌氧发酵产酸的代谢机理和微生物机理,对近年来污泥厌氧发酵产酸的研究成果进行了梳理,重点论述了底物种类、预处理技术、pH值、发酵温度等因素对污泥厌氧发酵产酸的影响及研究进展,总结并对比了不同底物类型、发酵温度、酸性和碱性条件下都可影响发酵产酸的产量及酸种类分布,而污泥预处理技术则倾向于提高酸的产量,对酸种类分布影响不大。介绍了污泥厌氧发酵产酸在合成PHAs、生物能源和污水的脱氮除磷等方面的应用情况。最后,针对污泥厌氧发酵产酸会因底物有机成分不同,导致酸化效率有所差异,同时控制底物种类、pH值和温度等因素不仅影响产酸量,还会影响产酸类型和产物种类。提出了今后的研究方向主要是深入分析不同底物的酸化效率差异原因、污泥定向发酵产酸,实现总VFAs中各种酸比例调控。     

硫酸镓改性离子交换树脂催化合成丁酸异戊酯

以硫酸镓与阳离子交换树脂反应制备的改性离子交换树脂为催化剂,正丁酸和异戊醇为原料合成了丁酸异戊酯。考察了催化剂用量、醇酸物质的量比、反应时间、带水剂种类及催化剂重复使用次数等因素对酯收率的影响。结果表明该催化剂与反应体系形成非均相物系,具有易分离回收,催化活性高,反应时间短,出水速率快,合成工艺流程简单,操作方便,不易腐蚀设备,废液排放量少,不需加带水剂即可获得较为理想的收率等优势。适宜反应条件为：正丁酸0．1mol,醇酸物质的量比1．4,催化剂1．0g,反应时间40min,酯收率达91．0％。     

硫酸高铈改性离子交换树脂催化合成异戊酸丁酯

采用硫酸高铈与阳离子交换树脂反应制备的改性离子交换树脂催化合成了异戊酸丁酯。考察了催化剂用量、醇酸物质的量比、反应时间及带水剂等因素对收率的影响。适宜反应条件：异戊酸用量为0.2 mol,醇酸物质的量比为1.6,催化剂用量为2.0 g,反应时间为60 min,苯用量为5 mL,收率可达91.3%。     

水处理中离子交换树脂再生时酸碱耗的降低

为了降低水处理中离子交换树脂再生时的酿碱耗，根据生产上对水质要求，水处理的设备、工艺条件等情况，采用逆流再生双层床工艺，通过调整试验确定最优酸碱耗，酸耗＜40-45g／mo1；碱耗63．85g／mo1。提高了总平均工作交换容量，取得了较好的经济效益。     

D301阴离子交换树脂吸附2-酮基-L-古龙酸母液中草酸的研究

研究了分离出2-酮基-L-古龙酸母液中的草酸时,D301阴离子交换树脂在静态和动态情况下吸附草酸的过程,并利用Freundlich吸附等温方程对吸附等温线数据进行拟合。结果表明:D301树脂对草酸的平衡吸附数据符合Freundlich吸附等温方程,在293、303、313K三种温度下相关系数均大于0.99;且在pH值为6、温度313K、流速30mL/min时吸附量达到最大。这些研究为从古龙酸母液中除去或者回收草酸找到了一种有效的方法,并且可降低母液的COD值,从而降低污染。     

Regeneration of Mixed Solvent by Ion Exchange Resin: Selective Removal of Chloride and Sulfate

Abstract

The selective extraction of sulfate and chloride ions from mixed solvent solutions was investigated. The mixed solvents consisted of water and 50 to 100%‐w (salt‐free solvent) ethylene glycol. The extraction was measured for mixed solvent solutions containing only sulfate and chloride, and mixed solvent solutions saturated with trona (sodium sesquicarbonate, Na₂CO₃ · NaHCO₃ · 2H₂O(s). Three anion exchange resins, Dowex 1X8‐50, Dowex 21K‐Cl, and Dowex MSA‐1, were investigated for their chemical and physical resistance to the mixed solvent carbonate/bicarbonate solutions, for their swelling behavior in the different mixed solvents, and for their extraction efficiency for chloride and sulfate.

The loading of the ion exchangers was fitted to a Langmuir‐type sorption model. While the extraction from trona‐free mixed solvents was well reproduced, the loading of the ion exchangers with chloride and sulfate from trona‐saturated mixed solvent solutions did not fit the sorption model. It appears, rather, that under these conditions chloride and sulfate are “salted out” of the bulk solution and driven into the ion exchangers.     

离子交换法去除有机二胺吸收剂PA-A中的SO42-平衡及动力学研究

研究了大孔阴离子交换树脂对有机二胺吸收剂PA-A中SO42-的吸附相平衡和动力学行为。结果表明,D296型树脂对SO42-具有良好的吸附选择性,333K下的吸附容量可达100.20mg.g-1。Langmuir-Freundlich模型能较好地描述吸附交换行为。吸附过程符合Lagergren一级动力学模型。液膜扩散为吸附速率的主要控制步骤。     

Esterification of Pentanoic Acid with 1-Propanol by Sulfonated Cation Exchange Resin: Experimental and Kinetic Studies

Liquid-phase esterification reaction of 1-propanol with pentanoic acid to give propyl pentanoate over Amberlyst 15 has been studied. The reaction carried out in a batch reactor was found to be independent of mass transfer effects in the temperature range of 323.15–363.15 K. The reaction is highly temperature sensitive. Increase in 1-propanol concentration has an enhancing effect on the conversion, whereas water acts as an inhibitor. As alcohol–acid mixtures behave nonideally, kinetic analysis has been performed using UNIFAC liquid-phase activities of pentanoic acid, 1-propanol, propyl ester, and water. Observed kinetics is best represented by Eley–Rideal mechanism. Surface reaction was observed to be a rate-limiting step.     

Adsorptive Removal of Nitrate and Phosphate from Water by a Purolite Ion Exchange Resin and Hydrous Ferric Oxide Columns in Series

Elevated concentrations of nitrate and phosphate in surface and ground waters can lead to eutrophication, and nitrate can also cause health hazards to humans. The adsorption process is generally considered to be an efficient technique in removing these ions provided that the adsorbent is highly selective for these ions. Removal of nitrate and phosphate from a synthetic water (50 mg N/L as nitrate, 15 mg P/L as phosphate) and a wastewater (12.9 mg N/L as nitrate, 5.9 mg P/L as phosphate) using a Purolite A500P anion exchange resin and a hydrous ferric oxide (HFO) columns (60 cm height, 2 cm diameter, flow rate 1 m/h) in series containing 1–10% (w/w) of these adsorbents and the remainder anthracite (90–99%) were studied. Data from batch adsorption experiment at various concentrations of adsorbents satisfactorily fitted to Langmuir adsorption isotherm for nitrate and phosphate on Purolite with adsorption maxima of 64 mg N/g and 7 mg P/g and only for phosphate on HFO with adsorption maxima of 14 mg P/g. Both batch and column experiments showed that Purolite selectively removed nitrate and HFO selectively removed phosphate. The Purolite column BTC time was greater for nitrate than for phosphate. At the highest percentage by weight of Purolite almost all nitrate was removed in batch study and up to 1000 min in column study, but it was not able to remove a comparatively high percentage of phosphate. However, when the effluent from the Purolite column was passed through the HFO column almost all phosphate was removed. The two columns when set up in series also removed almost all nitrate and phosphate from the wastewater.     

Activation of Free Fatty Acid Receptor 4 (FFA4) Ameliorates Ovalbumin-Induced Allergic Asthma by Suppressing Activation of Dendritic and Mast Cells in Mice

Epidemiological and clinical studies have suggested that intake of n-3 polyunsaturated fatty acids (PUFA) reduces the incidence of allergic airway diseases and improves pulmonary function in patients with allergic asthma. However, the pharmacological targets of PUFA have not been elucidated upon. We investigated whether free fatty acid receptor 4 (FFA4, also known as GPR120) is a molecular target for beneficial PUFA in asthma therapy. In an ovalbumin (OVA)-induced allergic asthma model, compound A (a selective agonist of FFA4) was administrated before OVA sensitization or OVA challenge in FFA4 wild-type (WT) and knock-out (KO) mice. Compound A treatment of RBL-2H3 cells suppressed mast cell degranulation in vitro in a concentration-dependent manner. Administration of compound A suppressed in vivo allergic characteristics in bronchoalveolar lavage fluid (BALF) and lungs, such as inflammatory cytokine levels and eosinophil accumulation in BALF, inflammation and mucin secretion in the lungs. Compound A-induced suppression was not only observed in mice treated with compound A before OVA challenge, but in mice treated before OVA sensitization as well, implying that compound A acts on mast cells as well as dendritic cells. Furthermore, this suppression by compound A was only observed in FFA4-WT mice and was absent in FFA4-KO mice, implying that compound A action is mediated through FFA4. Activation of FFA4 may be a therapeutic target of PUFA in allergic asthma by suppressing the activation of dendritic cells and mast cells, suggesting that highly potent specific agonists of FFA4 could be a novel therapy for allergic asthma.