Triamine Penta Methylene Phosphonic Acid Research Articles

Influence of Several Phosphate-Containing Additives on the Stability and Electrochemical Behavior of Positive Electrolytes for Vanadium Redox Flow Battery

The poor operational stability of electrolytes is a persistent impediment in building redox flow battery technology; choosing suitable stability additives is usually the research direction to solve this problem. The effects of five phosphate containing additives (including 1-hydroxyethylidene-1,1-diphosphonic acid (HEDP), hexamethylene diamine tetramethylene phosphonic acid (HDTMPA), amino trimethylene phosphonic acid (ATMPA), sodium ethylenediamine tetramethylene phosphonate (EDTMPS), and diethyl triamine pentamethylene phosphonic acid (DTPMP)) on the thermal stability and electrochemical performance of the positive electrolyte of vanadium redox flow battery were investigated. With 0.5 wt% addition, most of the selected additives were able to improve the thermal stability of the electrolyte. HEDP and HDTMPA extended the stability time of the pentavalent vanadium electrolyte at 50 °C from 5 days (blank sample) to 30 days and 15 days, respectively. The electrochemical performance of the electrolyte was further investigated by cyclic voltammetry, steady state polarization, and electrochemical impedance spectroscopy tests. It was found that most of the additives enhanced the electrochemical activity of the positive electrolyte, and the diffusion coefficients, exchange current densities, and reaction rate constants of V(IV) species became larger with the addition of these additives. It is verified that the thermal stability and electrochemical stability of the electrolyte are significantly improved by the combination of ATMPA + HEDP or ATMPA + HDTMPA. This study provides a new approach to improve the stability of the positive electrolyte for vanadium redox flow battery.

Effect of antiscalants on organic fouling potential of rough membrane in membrane distillation: Focusing on the evaluation of interfacial interaction

Impacts of antiscalants on fouling potential of rough membranes were explored in membrane distillation (MD) system, and three antiscalants were applied in this study, including 2-phosphonobutane-1,2,4-tricarboxylic acid (PBTCA), diethylene triamine penta methylene phosphonic acid (DTPMPA), and polymaleic acid (HPMA). Deteriorated organic fouling caused by 150 mg/L lysozyme (LYS) solutions was observed with the addition of antiscalants in MD influent, due to variations of surface properties induced by adhesion of antiscalants. In MD operation of LYS solutions, a mild flux drop of 37.7% was obtained for unmodified PTFE membrane, while PBTCA, DTPMPA, and HPMA groups all demonstrated severe flux decline of 58.4%, 46.4%, and 63.5%, respectively. Methods of surface element integration and extended Derjaguin-Landau-Verwey-Overbeek (XDLVO) theory were applied to estimate interfacial interaction among foulants-reconstructed membrane surface. MD membranes initially adhered by PBTCA and HPMA both demonstrated higher surface roughness and correspondingly lower energy barrier, promoting sharper depositions of LYS and faster flux decline. A four-stage pattern was roughly proposed for organic fouling development in MD, which was notably affected by adherence of antiscalants. Comparatively, MD membranes adhered by DTPMPA displayed relatively lower surface roughness and higher interaction energy barrier, suggesting that DTPMPA might be a feasible method for MD fouling mitigation.

Zero liquid discharge treatment of brackish water by membrane distillation system: Influencing mechanism of antiscalants on scaling mitigation and biofilm formation

• The anti-scaling performance of PBTCA, DTPMPA, and HPMA in MD system was studied. • Regulation mechanism of antiscalant on the MD fouling layer formation was presented. • Usage of DTPMPA in MD existed the risk of phosphate crystals and membrane wetting. • HPMA was suitable for the long-term operation of zero-liquid discharge MD system. Membrane distillation (MD) is increasingly regarded as a promising technique for brine management and zero liquid discharge (ZLD) disposal of seawater and brackish water owing to its excellent effluent quality and higher salt tolerance. However, membrane fouling issues of MD, especially scaling, have been confirmed as a crucial challenge impeding its large-scale utilization. Presently, the scaling issue of conventional membrane-based desalination techniques including reverse osmosis (RO) and ultrafiltration (UF), has been effectively controlled via the usage of antiscalants. Hence, this work applied three representative antiscalants of 2-phosphonobutane-1,2,4-tricarboxylic acid (PBTCA), diethylene triamine penta methylene phosphonic acid (DTPMPA), and polymaleic acid (HPMA) in MD devices to restrain the scaling of polytetrafluoroethylene (PTFE) membrane during the ZLD treatment of synthetic brackish water. Furthermore, influences of antiscalant presence on variations of feed water qualities and the corresponding biofilm formation were also comprehensively studied via the high throughput sequencing method of 16S rDNA and 16S rRNA as well as a confocal laser scanning microscopy (CLSM). Compared to DTPMPA (77.4%-97.8%) and HPMA (42.1%-97.8%), a higher anti-scaling efficiency was obtained for PBTCA (90.6%-98.1%) in MD system, while the membrane biofilm formed in PBTCA group exhibited a remarkable appearance of live cells (14.046 μm 3 /μm 2 ). The secondary fouling of phosphate scale and pore wetting might be induced by the utilization of DTPMPA in MD plants, sharply increasing the effluent conductivity to 176.4 μS/cm (12 d). Comparatively, HPMA could be largely combined with salt ions to form loose slags with good fluidity, promoting the reuse of MD membranes and the subsequent disposal of MD brine.

A novel durable flame retardant for cotton fabrics based on diethylenetriamine

A novel flame retardant, diethylenetriamine pentamethyl triphosphonate methyl ester ammonium diphosphonate flame retardant (DETA-P), was synthesized and characterized by NMR and FTIR. DETA-P-treated cotton fabrics showed excellent flame retardancy and durability. The limiting oxygen index (LOI) of cotton fabrics treated with 30 wt% DETA-P reached 40.7% and after 50 laundering cycles (LCs), according to the AATCC 61-2013 2A standard, still reached 29.0%. The energy dispersive X-ray (EDX) results of showed that there were P and N elements in CF-3. After 50 LCs, the total metal ion content of DETA-P treated cotton was noticeably lower than that of ammonium salt of diethylene triamine penta methylene phosphonic acid (ADTPMPA)-treated cotton. The scanning electron microscopy (SEM) and EDX results suggested that DETA-P molecules entered the cotton fiber interior. The results of the Fourier transform infrared (FTIR) and durability analyses showed that DETA-P grafted the –OH of cellulose molecules through P–O–C in cotton fibers. Thermogravimetry (TG) results showed that DETA-P changed the thermal decomposition pathway of cotton fibers. The cone calorimetry results indicated that the heat release rate and total heat release of DETA-P-treated cotton were much lower than for untreated cotton. These results showed that the introduction of phosphonate groups and reactive ammonium phosphorus acid groups into a flame retardant molecule was an effective method to improve the flame retardancy and durability of the cotton fibers.

Diethylene triamine penta methylene phosphonic acid encountered silver ions: a convenient method for preparation of flame retardant and antibacterial lyocell fabric

Diethylene triamine penta methylene phosphonic acid encountered silver ions: a convenient method for preparation of flame retardant and antibacterial lyocell fabric

Effect of DTPMPA on Bamboo Kraft Pulping

As a cooking additive, the impact of Diethylene Triamine Penta Methylene Phosphonic Acid (DTPMPA) on bamboo kraft pulping was studied. The effect of DTPMPA dosage at different maximum cooking temperature was discussed. The results showed that the cooking aids DTPMPA added in bamboo kraft pulping was able to reduce K value of pulp, improve the screened stock yield and brightness and reduce the alkali charge. The optimized bamboo kraft pulping conditions are: DTPMPA dosage 0.3%, alkali charge 17%, when sulfidity was 20%, maximum cooking temperature was 160°C and time at maximum temperature was 90min. Under the conditions of cooking, the screened yield is 41.53%, the K value is 15.4 and the bamboo pulp brightness is 26.8%.

Study on Bamboo Kraft Pulping with DTPMPA

DTPMPA (Diethylene Triamine Penta Methylene Phosphonic Acid) was used as cooking additive in Bamboo pulping. The effect of cooking parameters such as alkali charge, maximum cooking temperature, and time at maximum temperature on bamboo kraft pulping adding additive Diethylene Triamine Penta Methylene Phosphonic Acid was studied. The results show that the optimized bamboo kraft pulping conditions are: alkali charge 17%, maximum cooking temperature 162°C, and time at maximum temperature 60min when DTPMPA dosage is 0.4%. On the optimized conditions of cooking, the highest screened bamboo pulp yield 49.52%, the kappa number of bamboo pulp is 24.68, residual alkali in kraft waste liquor 3.62g/L .

Study on DTPMPA as Cooking Additive in Bamboo Pulping

The application of chelating agents DTPMPA (Diethylene Triamine Penta Methylene Phosphonic Acid) as cooking aids in kraft pulping of bamboo was researched. The effect of DTPMPA dosage at different alkali charge was discussed. The results showed that the cooking aids DTPMPA added in bamboo kraft pulping was able to reduce K value of pulp, improve the screened stock yield and brightness and reduce the alkali charge. The optimized bamboo kraft pulping conditions are: DTPMPA dosage 0.4%, alkali charge 19%, when sulfidity was 20%, maximum cooking temperature was 165°C and time at maximum temperature was 90min. Under optimized conditions of cooking, the screened bamboo pulp yield is higher, the K value is lower and the bamboo pulp brightness is higher.

Application of Chelating Agents as Cooking Aids in Bamboo Pulping

The effect of chelating agents Diethylene Triamine Penta Methylene Phosphonic Acid in bamboo kraft cooking was studied. The results show that the bamboo pulp yield was 49.52% when DTPMPA dosage is 0.4%, at the same time the Kappa number was lower. With the increasing of DTPMPA dosage in bamboo kraft pulping, the bamboo pulp strength was increased.

The Inhibition Effect of Corrosion of Carbon Steel in Seawater by Diethylene Triamine Pentamethylene Phosphonic Acid and Al3+ System

The inhibition of the corrosion of carbon steel in seawater by diethylene triamine pentamethylene phosphonic acid (DTPMP) and Al 3+ has been investigated using weight loss and electrochemical measurements. The results show that 65% inhibition efficiency is achieved with binary system consisting of 250 ppm of DTPMP and 50 ppm of Al 3+ . Polarization curves indicate that the system is a mixed inhibitor. The surface morphology of the metal surface is examined using the scanning electron microscope.

THE INHIBITIVE EFFECT OF DIETHYLENE TRIAMINE PENTAMETHYLENE PHOSPHONIC ACID ON THE CORROSION OF CARBON STEEL IN SEAWATER

The inhibition of the corrosion of carbon steel in seawater by diethylene triamine pentamethylene phosphonic acid (DTPMP) and Ni 2+ has been investigated using weight loss and electrochemical measurements. The results show that 70% inhibition efficiency is achieved with binary system consisting of 250 ppm of DTPMP and 50 ppm of Ni 2+ .Polarization curves indicate that the system functioned as a cathodic inhibitor. AC impedance spectra reveal that a protective film is formed on the metal surface. The protective film has been analysed by FTIR spectra. The surface morphology and the roughness of the metal surface have been analysed by atomic force microscopy.

Application of Diethylene Triamine Penta Methylene Phosphonic Acid in Bamboo Pulping

The effect of Diethylene Triamine Penta Methylene Phosphonic Acid in bamboo kraft cooking was studied. The results show that the bamboo pulp properties are optimal when DTPMPA dosage is 0.4%. The optimal properties are as follows: the kappa number is 16.4, brightness is 37.8%, and the screened yield is 41.9%.

The hydroxyl radical scavenging effect of textile preparation auxiliaries on the photochemical treatment of nonylphenol ethoxylate

The present paper deals with the effects of frequently used textile preparation chemicals and common ions on the H2O2/$UV-C treatment of a commercially important and slowly biodegradable nonionic surfactant, namely a nonylphenol bearing 10 ethoxylated chains. For this purpose, the effect of soda ash carbonate (0–5.0 g L−1), two phosphonic acid-based organic sequestering agents (0–2.5 g L−1) and chloride (0–3.0 g L−1) at two different pH values (3.5 and 10.5) as hydroxyl radical scavengers was experimentally investigated. Among the studied textile preparation chemicals and hydroxyl radical scavengers, the decreasing order of hydroxyl radical scavenging capacity was established as diethylene triamine penta-methylene phosphonic acid>1-hydroxy ethylidene-1,1-diphosphonic acid>soda ash carbonate at pH 10.5>chloride at pH 3.5>chloride at pH 10.5.

Pb2+ selective and highly cross-linked zirconium phosphonate membrane by sol–gel in aqueous media for electrochemical applications

Zirconium diethylene triamine pentamethylene phosphonic acid (ZrD) was synthesized and showed high adsorption capacity for Pb2+. Cross-linked ZrD nanocomposite Pb2+ selective membrane was prepared by sol–gel using poly(vinyl alcohol) (PVA) as plasticizer in aqueous media. Developed ZrD nanocomposite membrane showed good thermal, mechanical and chemical stabilities, which are essential parameters for its durability. Furthermore, conductivity and counter-ion transport studies of these membranes suggested their potential application for separating Pb2+ by electrodialysis (ED). Electro-dialytic studies revealed very high Pb2+ flux across ZrD membranes in comparison with other bi-valent metal cations (Cu2+, Cd2+ and Ni2+). Relatively high retention of Pb2+ in the membrane phase was attributed to its controlled cross-linked structural morphologies, and completely intermingled and well connected network between the metal phosphonates and the polymeric backbone. Furthermore, high separation factor (2.0–3.0) for separating Pb2+/Cu2+, Pb2+/Cd2+, and Pb2+/Ni2+, suggested practical applications of developed membrane for electro-dialytic fractionation/removal of Pb2+ from industrial waste water.

Effect of pH on Material Removal Rate of Cu in Abrasive-Free Polishing

The effect of pH on the material removal rate (MRR) of Cu in an organic phosphonic acid system abrasive-free slurry was investigated by thermodynamics, X-ray photoelectron spectroscopy analysis, and electrochemical measurements. The pH range can be divided into three chemical regions according to the evolution of the polishing MRR, which relies on the effect of pH on the chelating effect of the chelating ligand, diethylene triamine penta methylene phosphonic acid. The higher the pH is, the more efficient the chelating ligand is. In the alkaline pH region, because of the enhanced chelating effect and precipitation of the chelate complex on the surface, both the MRR and friction coefficient during polishing process increase significantly, and the corrosion current acquired from the potentiodynamic polarization measurement decreases.