Removal of Co(Ⅱ) from aqueous solutions by NKC-9 strong acid resin

A strong acidic ion exchange resin(NKC-9)was used as a new adsorbent material for the removal of Co(Ⅱ)from aqueous solutions.The adsorption isotherm follows the Langmuir model.The maximum adsorption capacity of the resin for Co(Ⅱ)is evaluated to be 361.0 mg/g by the Langmuir model.It is found that 0.5 mol/L HCl solution provides effectiveness of the desorption of Co(Ⅱ)from the resin.The adsorption rate constants determined at 288,298 and 308 K are 7.12×10-5,8.51×10-5and 9.85×10-5s-1, respectively.The apparent activation energy(Ea)is 12.0 kJ/mol and the adsorption parameters of thermodynamic are-H Θ=16.1 kJ/mol,-SΘ=163.4 J/(mol·K),-G Θ 298 K=-32.6 kJ/mol,respectively.The adsorption of Co(Ⅱ)on the resin is found to be endothermic in nature.Column experiments show that it is possible to remove Co(Ⅱ)ions from aqueous medium dynamically by NKC-9 resin.

Adsorption equilibrium, kinetics, and dynamic separation of Ca2+ and Mg2+ ions from phosphoric acid–nitric acid aqueous solution by strong acid cation resin

The separation of Ca2+and Mg2+ions from phosphoric acid-nitric acid aqueous solution is very significant for the neutralization process of nitrophosphate fertilizer.This paper studied the adsorption equilibrium,kinetics,and dynamic separation of Ca2+and Mg2+ions by strong acid cation resin,and the effects of phosphoric acid and nitric acid on the adsorption process were investigated.The results reveal that the adsorption process of Ca2+and Mg2+ions in pure water on resin is in good agreement with the Langmuir isotherm model and their maximal adsorption capacities are 1.86 mmol·g-1 and 1.83 mmol·g-1,respectively.The adsorption kinetics of Ca2+and Mg2+ions on resin fits better with the pseudo-first-order model,and the adsorption equilibrium in pure water is reached within 10 min contact time,while at the present of phosphoric acid,the adsorption rate of Ca2+and Mg2+ions on resin will go down.The dynamic separation experiments demonstrate that the designed column adsorption is able to undertake the separation of metal ions from the mix acids aqueous solution,but the dynamic operation should control the flow rate of mix acid solution.Besides nitric acid solution was proved to be effective to completely regenerate the spent resin and achieve the recyclable operation of separation process.

Determination of Molecular Mass of Strong Acids by Differential Temperature Model (DTM) Using H₃PO₄and HBF₄for Classical Demonstration

A new chemical hypothesis based on the differential temperature model (DTM) for estimation of molecular masses of some strong acids (H2SO4, HNO3 and HCl) in solutions have previously been propounded and tested theoretically and analytically by the author. The results were published in the Bulletin of Pure and Applied Sciences–Chemistry in 2012. The changes in temperature following various dilutions of the acids were found to be proportional to their molecular properties. The new chemical hypothesis and model is hereby tested on H3PO4 and HBF4 and their exact molecular masses have been evaluated analytically and theoretically. The validity of the hypothesis and the model is hereby presented for chemical proof and adoption to theory by chemists.

Rapid analysis of metal ions and organic compounds in strong acidic solutions by nano-ESI mass spectrometry

Rapid analysis of metal ions and organic compounds in strong acidic solutions is of sustainable interest in multiple disciplines.However,complicated and time-consuming pretreatments are always required for MS analysis of the compounds in strong acidic solutions.Otherwise,it will result in a weak signal and cause serious damage to the mass spectrometer.Herein,a simple method inherited from nano-ESI MS was developed for rapid analysis of strong acidic solutions.Nanoliter(nL)strong acidic solution was first loaded in the nano-ESI emitter,followed by evaporation to remove the H+and leave the analytes on the wall of the nano-ESI emitter.The evaporation process can be completed within 1 min because of the extremely tiny volume(≤1 nL)of the loaded solution.Then,the dried analytes on the wall of the nano-ESI emitter were redissolved by loading a new solvent,followed by nano-ESI MS analysis.By using this method,metal ions and organic compounds in the strong acidic solution can be detected with low sample consumption(1 nL),high speed(<2 min/sample),high sensitivity(limit of detection=0.2µg/L),and high accuracy(>90%).Proof-of-concept applications of the present method have been successfully achieved for the analysis of gastric juice(pH of the sample=1),monitoring reaction catalyzed by strong acid(pH of the system=0),and micro-area analysis of ores(pH of the extraction solvent=0),showing great application potential in multiple fields.

Adsorption behavior and mechanism of cadmium on strong-acid cation exchange resin

The adsorption behavior of Cd2+ on 001×7 strong-acid cation exchange resin was studied with the static adsorption method. The adsorption process was analyzed from thermodynamics and kinetics aspects. The influences of experimental parameters such as pH, temperature, initial concentration and adsorption rate were investigated. The experimental results show that in the studied concentration range, 001×7 resin has a good sorption ability for Cd2+, and the equilibrium adsorption data fit to Freundlich isotherms. The adsorption is an exothermic process which runs spontaneously. Kinetic analysis shows that the adsorption rate is mainly governed by liquid film diffusion. The best adsorption condition is pH 4-5. The saturated resin can be regenerated by 3 mol/L nitric acid, and the desorption efficiency is over 98%. The maximal static saturated adsorption capacity is 355 mg/g (wet resin) at 293 K. The adsorption mechanism of Cd2+ on 001×7 resin was discussed based on IR spectra.

High efficient acetalization of carbonyl compounds with diols catalyzed by novel carbon-based solid strong acid catalyst

The novel carbon-based acid catalyst has been applied to catalyzing the acetalization and ketalization. The results showed that the catalyst was very efficient with the average yield over 93%. The novel het- erogeneous catalyst has the advantages of high activity, wide applicability even to 7-membered ring acetals, strikingly simple workup procedure, non-pollution, and reusability, which will contribute to the green process greatly.

ENCAPSULATION OF STRONG SOLID ACID NANOPARTICLES IN MESOPOROUS CHANNEL HOSTS

Mesoporous molecular sieve with Al-promoted sulfated rirconia (SZA) based strong solid acid nano-particles within its mesoporous channels was synthesized by using a one-step incipient wetness impregnation method with zirconium sulfate and aluminum sulfate as the precursors. The assemblies of SZA/MCM-41 were obtained by thermal decomposition of the precursors in air.The resultant composite was characterized with various techniques such as nitrogen physisorption, X-ray diffraction, SEM and TEM. It was shown that the well-ordered channels of MCM-41 arranged in hexagonal arrays as well as the hollow tubular morphology was retained. The strong solid acid nanoparticles were isolated born each other and highly, dispersed in the channels. Nitrogen sorption showed the expected decrease in pore volume. The catalytic activity of SZA/MCM-41 composite in the isomerization of n-butane was dramatically improved in comparison to bulk SZA or SZA/silica.

Clinical Evaluation of an Oral Electrolyte Solution Formulated Based on Strong Ion Difference (SID) and Using Propionate as the Organic Anion in the Treatment of Neonatal Diarrheic Calves with Strong Ion Acidosis

Background: It is postulated that the concentrations of the major strong ions (Na, K, and Cl) in oral electrolyte solutions play a major role in clinical efficacy of these solutions for rehydration and corrections of metabolic acid base derangements. Objectives: The purpose of this study was to test prospectively the efficacy of an OES (OESexp) formulated based on concentration of strong ion difference (SID) and propionate in a group of calves with naturally occurring neonatal diarrhea and clinically detectable dehydration and acid base abnormalities. Animals: Ten client owned calves of varying breeds, 2 - 22 days old, presented to a veterinary teaching hospital with a history of naturally occurring acute undifferentiated diarrhea, progressive depression and dehydration for treatment. Methods: Clinical and laboratory parameters were measured pre and post two oral electrolyte treatments to assess efficacy of the experimental OES to correct clinical and clinico pathological parameters. For the clinical trial the calves served as their own controls. For control of safety of medication 4 normal calves were force fed 4 L of OESexp and followed over a 24 hour period. Results: All calves had severe diarrhea and metabolic acidosis. The metabolic acidosis observed in the plasma of these calves and reflected by pH, HCO3- SID and base deficit was corrected significantly towards reference ranges (p < 0.05) with two 2 L feedings 12 hours apart. Dehydration was significantly corrected and all calves were discharged 1 - 3 days post admission. Conclusion and Clinical Importance: The use of SID is a valid approach when formulating oral electrolytes solutions for use in calves with acute diarrhea and metabolic derangement. Sodium propionate is valid substitute for commonly used sodium base equivalents in North America in oral electrolyte solutions.

Acetalization of carbonyl compounds with 2,2,4-trimethyl-1,3-pentanedio catalyzed by novel carbon based solid acid catalyst

The synthesis of 2, 4-diisopropyl-5,5-dimethy1- 1.3-dioxane through the acetalization of isobutyraldehyde with 2, 2, 4-trimethy1-1,3-pentanediol （TMPD） catalyzed by the novel carbon based acid was first carried out. High conversion （≥98%） and specific selectivity were obtained using the novel carbon based acid, which kept high activity after it was reused 5 times. Moreover. the catalyst could be used to catalyze the acetalization and ketalization of different aldehydes and ketones with superior yield. The yield of several products was over 90%. The novel heterogeneous catalyst has the distinct advantages of high activity, strikingly simple workup procedure, non-pollution, and reusability, which will contribute to the success of the green process greatly.

Comparative Study between Traditional Approach and Physico-Chemical Approach in Acid Base Disorders Interpretation in Critically Ill Patients

Objective: The traditional approach for acid base interpretation is based on Handerson-Hasselbalch formula and includes Base Excess (BE), bicarbonate (HCO3), albumin corrected anion gap. The Physicochemical approach is centered on the Carbon Dioxide tension (PCO2), the strong ion difference (SID), strong ion gap (SIG) = SID apparent-SID effective and totally weak acids (Atot). The study aims to compare between the traditional approach and the physicochemical approach in acid base disorder interpretation. Design: Prospective observational study in an adult Intensive Care Unit (ICU) recruiting six hundred and sixty one patients. Methods: Arterial blood samples were analyzed to measure pH, PaCO2 sodium, potassium, chloride and lactate. Venous blood samples were analyzed to measure ionized calcium, magnesium, phosphorous and albumin. These samples were interpreted by both techniques. Results: Normal HCO3 and BE were detected by traditional approach in 49 cases of which SIG acidosis was detected in 22 cases (46%) and Hyperchloremic acidosis was detected in 29 cases (60%) by physicochemical method. SIG was elevated in 72 cases (58%) of 124 cases with high anion gap acidosis. SIDeff and BE were strongly correlated, r = 0.8, p 0.0001, while SIG and Albumin corrected Anion Gap (ALAG) were moderately correlated r = 0.56, p Conclusion: Both approaches are important for interpretation of the acid base status. Traditional approach identifies the diagnostic description without many calculations and detects body compensatory response to acid base disorders. Physicochemical approach is essential to identify the exact causation and the severity of the acid base disorders.

强缓速低摩阻低伤害纳米均相缓速酸

针对碳酸盐岩储层改造乳化酸高摩阻、稠化酸聚合物残渣伤害问题,首先通过拟三元相图,以非离子型表面活性剂(三苯乙烯基苯酚聚氧乙烯醚)、阳离子型表面活性剂(季铵盐)、助表面活性剂(醇)为原料制备纳米乳液,然后将20%盐酸、5%纳米乳液、0.1%减阻剂(阳离子聚丙烯酰胺)及功能型添加剂混合制得纳米均相缓速酸。采用旋转岩盘仪、扫描电镜、EDS能谱仪、电导率仪、粒度分析仪、界面张力仪、润湿角测定仪、摩阻仪、酸蚀裂缝导流仪、岩心流动仪等评价了纳米均相缓速酸的性能,分析了缓速机理、高酸蚀裂缝导流机理和溶垢机理。结果表明,纳米均相缓速酸是一种内相为油、外相为酸的纳米均相分散体系,粒径分布为8~100 nm;其具备强缓速(缓速率大于90%)、低摩阻(降阻率大于75%)、低黏、低伤害和高酸蚀裂缝导流性能;可同时溶解有机垢和无机垢,对沥青和碳酸盐岩的溶解率分别为6.91%和100%;可解除储层乳化、水锁、润湿改性伤害。纳米均相缓速酸通过带负电纳米乳液吸附在带正电灰岩表面,建立酸岩“隔离屏障”,实现强缓速;通过差异化酸蚀及黏性指进,实现高酸蚀裂缝导流;通过纳米乳液特殊的油水互溶结构,实现有机垢和无机垢的同时解除。该体系在海上油田现场成功应用,增产效果显著,对碳酸盐岩储层深部改造及多重伤害解除具有重要意义。

强非均质砂岩清洁暂堵转向酸化研究:以塔中志留系为例

酸化是低渗砂岩油藏有效开发的主要改造手段之一。塔中志留系储层小层多,非均质性强,酸化中酸液易进入高渗层,导致低渗层改造欠缺,目前尚无合适的砂岩转向酸化技术。本文采用了可完全水溶降解的清洁暂堵粉末,并配合螯合酸解决了非均质砂岩储层均匀酸化难题。通过并联岩心酸化流动仪,研究了清洁暂堵粉末封堵特性和不同级差下暂堵转向酸化能力。室内实验结果表明,清洁暂堵粉末降解主要受温度控制,在超过90℃后完全降解,降解后溶液清澈透明,且呈酸性,有效提升岩心渗透率20%。浓度为0.1%的暂堵粉末随螯合酸注入岩石后,能够形成内外阻挡层,增加暂堵表皮系数,最大封堵压差可达1.87 MPa,是单纯注螯合酸酸的6.7倍。并联岩心酸化实验表明100目清洁暂堵粉末在0.1%使用浓度下适用于渗透率级差小于15的储层,可有效降低岩心渗透率非均质差异,提高低渗岩心改造程度。此外,在塔中11-9井酸化施工中,暂堵转向酸化后增压效果明显,酸化后产量大幅增加。现场试验及应用证明,暂堵转向酸化技术在志留系储层取得了良好的增产改造效果,对长井段非均质砂岩储层酸化均匀改造具有重要的借鉴意义。

窖池中酸性脲酶产生菌的分离鉴定及其对模拟窖泥pH值和风味物质的影响

为改善窖池老化现象,该文从水井坊窖泥中分离酸性脲酶产生菌,将分离株与产香克氏梭菌S008复配后固态发酵,探究酸性脲酶产生菌对模拟窖泥pH值及挥发性风味物质影响。结果表明,筛选出4株酸性脲酶产生菌,鉴定并命名为布氏乳杆菌S162、科氏葡萄球菌S163、鲁梅利芽孢杆菌S164和水原拉梅尔芽孢杆菌S165;4株菌的脲酶活性在0.45~1.51 U/mL;复配菌株的模拟窖泥pH值呈现:上部>中部>下部,其中S163的模拟窖泥pH值最高(P<0.05)。在风味物质检测中,协同发酵后S163乙醛含量(2.38 mg/100 mL)最高,而S162乙缩醛含量(2.50 mg/100 mL)最高;正丙醇、正丁醇、正己醇和异戊醇含量分别是S008单菌发酵的1.41~1.97倍、0.92~1.85倍、0.66~1.58倍、1.13~1.69倍;S164与S008协同发酵对己酸含量提升最显著(P<0.05);4株菌与S008协同发酵可以分别提高“四大酯”含量2.66~5.02倍、1.21~4.85倍、1.33~3.31倍、1.27~2.86倍。研究表明,酸性脲酶产生菌与克氏梭菌S008协同发酵可以不同程度提高模拟窖泥pH值及主要挥发性风味物质含量。

多级循环加载下强酸作用混凝土力学响应及微观结构差异分析

自然与强酸作用混凝土在多级循环加载作用下的强度劣化及声发射特征对混凝土结构稳定性评估至关重要,通过开展自然与强酸作用混凝土多级循环加载试验,探究自然与强酸作用混凝土在单轴线性加载和分级循环加卸载作用的混凝土强度劣化特性以及各分级声发射集中趋势特征。结果表明:强酸作用混凝土在单轴多级循环加载下的强度下降明显,表现为强酸作用和多级循环加载应力路径两者都对混凝土强度有劣化作用,其中多级循环加载应力路径对强度的降低作用比强酸作用明显;在单轴多级循环加载下,混凝土的声发射事件主要出现在加载阶段,且极大值出现在每个循环的中部或峰值附近,而卸载阶段只有较少的声发射事件;除最后一次分级加载至破坏阶段,强酸作用混凝土各分级加载阶段的声发射信号没有自然状态混凝土剧烈,表现为强酸作用混凝土各分级加载阶段声发射振铃计数和能量的均值和最大值均小于自然状态混凝土,在最后一次分级加载至破坏阶段,强酸作用混凝土各分级加载阶段的声发射信号比自然状态混凝土剧烈,表现为强酸作用混凝土振铃计数和能量的均值及最大值略高于自然状态混凝土;试验混凝土内部孔隙和裂隙较为发育,孔隙以簇状和圆形为主,有块状孔隙密集区,裂隙呈条状和不规则状,混凝土内部层状结构明显,层状结构和孔隙裂隙交替分布在混凝土内部;研究成果可为扰动作用下混凝土结构稳定性评估提供科学依据。

低毒环保型溶剂对临时保护性可剥离涂料性能的影响探究

为制备绿色环保,对大气环境和人员健康均友好的临时保护性可剥离涂料,采用D40和200#溶剂油组成的复合溶剂溶解主成膜树脂,辅以耐老化树脂,添加合适的补强填料和助剂,制备了一种不起泡、开裂、脱落的高性能临时保护性可剥离涂料。该涂料附着力良好,又较易完整去除,还对强酸、强碱的浸蚀作用具有较强的耐受性及长效耐候性。与传统的以苯类混合溶剂制备的临时保护性可剥离涂料对比可知,该涂料黏度更低,工艺性更好,综合性能相当,但对施工人员及环境更加友好。

浓香型白酒发酵体系中己酸菌的研究进展

浓香型白酒发酵体系中己酸生成菌(以下简称“己酸菌”)的己酸合成代谢对提高浓香型白酒的发酵质量非常重要。因此,有必要深入全面了解浓香型白酒发酵体系中己酸菌的种类及其己酸合成代谢特征。本综述介绍了目前浓香型白酒发酵体系中已经分离的己酸菌株的种类多样性、系统进化关系、生理代谢特征、己酸合成代谢机制以及其与己酸菌、非己酸菌之间的协同代谢关系。本文可为理解己酸菌群在浓香型白酒发酵体系中的原位己酸合成代谢规律提供参考,为将来靶向提高己酸菌群在浓香型白酒发酵和生物质转化高附加值己酸工艺中进行己酸合成培养工程的应用提供理论依据。

浓香型白酒窖泥己酸菌的研究进展

浓香型白酒是中国白酒的重要类型之一,己酸乙酯是浓香型白酒特征风味物质,该物质合成所需的前体己酸主要依靠发酵过程中的己酸菌代谢生成。己酸菌的分离、鉴定及代谢功能研究已成为白酒品质提升相关领域的研究热点之一。本文综述了窖泥中己酸菌的分离概况,介绍了浓香型白酒发酵系统中常见的3种己酸菌及己酸的合成途径,探讨了pH及底物组成对己酸产量的影响;此外,介绍了微生物群落中其他微生物对己酸菌的影响,以期通过探讨浓香型白酒发酵体系中微生物驱动己酸形成的机制及其影响因素,为提升浓香型白酒品质提供理论基础。

两种不同工艺合成脲醛树脂胶黏剂在纤维板上的应用对比

探讨了两种工艺合成的改性脲醛树脂胶黏剂在高密度纤维板上的应用情况。在甲醛/(尿素+三聚氰胺)物质的量比及三聚氰胺添加质量比例相同的情况下,使用强酸起始工艺合成的改性脲醛树脂胶黏剂制备的高密度纤维板24h吸水厚度膨胀率较低,相较于传统合成工艺,其性能优势显著。

强湿陷性黄土尾液库大坝加固后的稳定性研究

本次研究主要根据实测的坝体物理力学参数对存在隐患的尾液库大坝进行加固方案研究,提出一种斜卧式褥垫排渗体与强湿陷性黄土反坡加固技术,并对加固后的大坝进行渗流及稳定性研究,并进行加固改造研究。

强湿陷性黄土尾液大坝在超震和千年一遇洪水下的加固研究

本次研究主要根据实测的坝体物理力学参数,对某尾液库进行渗流及稳定性研究,并进行加固改造研究,提出一种斜卧式褥垫排渗体与强湿陷性黄土反坡加固技术,使改造后的尾液库达到超震和千年一遇洪水下二等尾液库的安全使用要求。