The Study of Cadmium Wastewater Disposal by Heavy Metal Flocculant Polyhydroximic Acid

2012 ◽  
Vol 599 ◽  
pp. 372-377
Author(s):  
Bi Wang
Keyword(s):  
Heavy Metal ◽  
Sodium Hydroxide ◽  
Humic Acids ◽  
Ph Value ◽  
Removal Rate ◽  
Hydroxylamine Hydrochloride ◽  
Complexing Agents ◽  
Wastewater Disposal ◽  
Ph Values

Polyhydroximic acid (PHA) with the function of heavy metal flocculant was made by compounding polyacrylamide, hydroxylamine hydrochloride and sodium hydroxide, to observe its effects on the cadmium wastewater disposal under different conditions (pH value, different organic complexing agents EDTA, triammonium citrate, glycocoll, humic acids and turbidity). The present study reaches the following results: (1) PHA has good effects on the removal of Cd2+ in wastewater; for the sample wastewater with a concentration of 25 mg•L-1, the removal rate of Cd2+ can reach 94%; (2) The removal rate of Cd2+ rise with the rise of pH values(4-8); (3) EDTA can obviously inhibit PHA’s removal rate of Cd2+; (4) Triammonium citrate can improve PHA’s removing ability of Cd2+. (5) Glycocoll and humic acids can obviously enhance the removing of Cd2+; (6) Turbidity-causing materials can promote the removal of Cd2+ and turbidity.

The Treatment of Acid Copper-Containing Wastewater by Eggshell-Flyash System

2011 ◽  
Vol 183-185 ◽  
pp. 967-970
Author(s):  
Tao Liu
Keyword(s):  
Heavy Metal ◽  
Calcination Temperature ◽  
Removal Efficiency ◽  
Treatment Effect ◽  
Ph Value ◽  
Removal Rate ◽  
Good Treatment ◽  
Egg Shells ◽  
Egg Shell ◽  
Application Prospects

Removal efficiency of heavy metal Cu from acid wastewater using egg shell as adsorbent was investigated. The influence of calcination temperature and dosage of egg shell, as well as pH value on the removal efficiency were discussed to obtain the optimum removal condition. The results show that the removal rate of lead would achieve the best result of 99.56% when we use the egg shells calcined at 400°C,2h, and the content of egg shells is 30g/L, pH=3.0.Using eggshells to treat acid chrome-containing wastewater is simple and easy to be operated, which has application prospects for the process and good treatment effect.

Preparation of Xonotlite Whiskers from Carbide Slag

2010 ◽  
Vol 434-435 ◽  
pp. 787-789
Author(s):  
Fei Liu ◽  
Ling Ke Zeng ◽  
Jian Xin Cao ◽  
Qian Lin ◽  
Jing Li
Keyword(s):  
Ph Value ◽  
Raw Materials ◽  
Removal Rate ◽  
Hydrothermal Conditions ◽  
Hydrothermal Route ◽  
Synthesis Conditions ◽  
Ph Values ◽  
Carbide Slag ◽  
Xrd Techniques ◽  
First Time

Carbide slag was used as raw materials for the first time to prepare xonontlite whiskers via a hydrothermal route without special instruments and synthesis conditions. And the effect of pH value of emulsion of carbide slag and hydrothermal conditions on removal rate of impurities, morphology and crystallinity of synthesized xonotlite whiskers were explored using ICP, SEM and XRD techniques. The results indicated that the carbide slag after purification could be used to prepare xonotlite whiskers, and different pH values of emulsion of carbide slag had great impact on the removal rate of impurities and morphology of xonotlite whiskers. Xonotlite whiskers with 20-40 μm in length and 100-500 nm in diameter were hydrothermally synthesized at 230 °C for 15 h with using silicic acid as kiesel material.

Biohydrogen Production Using Anaerobic Fermentation at Various pH Values

2012 ◽  
Vol 512-515 ◽  
pp. 570-574
Author(s):  
Ying Chen ◽  
Kai Liu ◽  
Qing Gu ◽  
Min Liu
Keyword(s):  
Hydrogen Production ◽  
Propionic Acid ◽  
Acid Production ◽  
Production Efficiency ◽  
Ph Value ◽  
Anaerobic Fermentation ◽  
Removal Rate ◽  
Clean Energy ◽  
Brown Sugar ◽  
Ph Values

Hydrogen production with waste water can reduce pollution and produce clean energy at the same time. Hydrogen production is affected by many factors. In this experiment, with automatic fermentor, hydrogen and acid production, as well as organic removal rates from brown sugar wastewater by anaerobic cultures at various pH values, are studied. Results showed that the highest hydrogen production efficiency could be achieved when the pH value was maintained at 6.0. The maximum hydrogen production was 61.1mlH2/(g.VSS.d), and COD removal rate reached up to 33.8%, relatively higher than other pH values. The acid production was significantly improved under the condition of pH=4.5. However, the composition of VFAs was similar at the different pH values. The amount of acetic acid and butyric acid was account for about 90% of the final liquor products, and only a little propionic acid has being detected. The TOC removal rate in the system under different pH conditions are increase with pH value, but all below 10%. As the reaction proceeds, the propionic acid accumulation were also observed, higher pH could decrease the producing rate of it.

Removal of Perfluorooctanoate from Water by Polyaluminium Chloride Coagulation

2012 ◽  
Vol 610-613 ◽  
pp. 1784-1788
Author(s):  
Liu Yang ◽  
Li Zhao ◽  
Peng Yu Liu ◽  
Zong Shuo Li ◽  
Qing Chang
Keyword(s):  
Ph Value ◽  
Removal Rate ◽  
Mixing Time ◽  
Model Solution ◽  
Neutral Solution ◽  
Solution Ph ◽  
Polyaluminum Chloride ◽  
Ph Values ◽  
Coagulation Process ◽  
Slow Mixing

The removal of perfluorooctanoate （PFOA） and turbidity from model solution by coagulation was investigated. A polyaluminum chloride (PACl) was used as a coagulant in the coagulation process. The effects of coagulant dose, slow mixing time, solution pH value and initial turbidity on the removal of both PFOA and turbidity from water were studied. It was found that the removal rate of PFOA in water increase along with the increase in slow mixing time, initial turbidity and PAC dose. The removal rate of PFOA is more effective at the near neutral solution pH values and the high initial turbidity. The removal percents of PFOA exceed 80% at the optimal condition. The removal mechanism was speculated to be the electrostatic interaction and hydrophobic interaction in coagulation process.

Thermal Performance of Automobile Radiator Using Carbon Nanotube-Water Nanofluid—Experimental Study

2014 ◽  
Vol 6 (4) ◽  
Author(s):  
Sandesh S. Chougule ◽  
S. K. Sahu
Keyword(s):  
Heat Transfer ◽  
Nusselt Number ◽  
Carbon Nanotube ◽  
Ph Value ◽  
Removal Rate ◽  
Synthesis Method ◽  
Heat Removal ◽  
Nanoparticle Concentration ◽  
Transfer Enhancement ◽  
Ph Values

In the present study, the convective heat transfer enhancement of carbon nanotube (CNT)-water nanofluid has been studied experimentally inside an automobile radiator. Heat removal rate of the coolant flowing through the automobile radiators is of great importance for the optimization of fuel consumption. In this study, four different concentrations of nanofluids in the range of 0.15–1 vol. % were prepared with the addition of CNT nanoparticles into water. The CNT nanocoolants are synthesized by functionalization (FCNT) and surface treatment (SCNT) method. The effects of various parameters, namely synthesis method, variation in pH values and nanoparticle concentration on the Nusselt number are examined through the experimental investigation. Results demonstrate that both nanocoolants exhibit enormous change Nusselt number compared with water. The results of functionalized CNT nanocoolant with 5.5 pH exhibits better performance compared to the nanocoolant with pH value of 6.5 and 9. The surface treated CNT nanocoolant exhibits the deterioration in heat transfer performance. In addition, Nusselt number found to increase with the increase in the nanoparticle concentration and nanofluid velocity.

Study of Cadmium Wastewater Treatment with Polymer PHA Containing Hydroxamic Acid Groups

2012 ◽  
Vol 610-613 ◽  
pp. 1686-1690
Author(s):  
Bi Wang
Keyword(s):  
Heavy Metal ◽  
Wastewater Treatment ◽  
Reaction Time ◽  
Hydroxamic Acid ◽  
Ph Value ◽  
Removal Rate ◽  
Chelating Agent ◽  
Environmental Safety ◽  
Metal Chelating ◽  
Made In

Polymer heavy metal chelating agent containing hydroxamic acid groups (PHA) was made in order to observe its effects on the removal rate of Cd2+. The present study reaches the following results: (1) On conditions that pH value is 8.0, the chelating agent is 60mg•L-1and the reaction time is 60min, the highest chelating capacity of the polymer heavy metal chelating agent PHA can reach 341 mg/g. (2) The existence of common cations: K+, Na+and Mg2+can improve PHA’s ability to remove Cd2+. (3) The existence of common anions Cl-, SO42-and NO3-can improve PHA’s ability to remove Cd2+. (4) Co-existing with the turbidity-causing materials, PHA’s removal abilities of Cd2+and turbidity are mutually promotive. (5) The chelating product, Cd-PHA’s amount of leaching of Cd2+is only 1/11 of that in neutralization titration ,having a relatively higher stability and better environmental safety.

Comparison of chelating ion exchange resins in sorption of copper(II) and zinc(II) complexes with ethylenediaminetetraacetic acid (EDTA) and nitrilotriacetic acid (NTA)

2008 ◽  
Vol 86 (10) ◽  
pp. 958-969 ◽  
Author(s):  
Dorota Kołodyńska ◽  
Zbigniew Hubicki
Keyword(s):  
Heavy Metal ◽  
Functional Groups ◽  
Heavy Metal Ions ◽  
Ethylenediaminetetraacetic Acid ◽  
Ph Value ◽  
Nitrilotriacetic Acid ◽  
Complexing Agents ◽  
Ion Exchange Resins ◽  
Ion Exchangers ◽  
Exchange Resins

This paper investigates the macroporous chelating ion exchangers with different functional groups for their sorption properties towards the copper(II) and zinc(II) ions. The investigations by the dynamic and static methods were carried out in the presence of traditional complexing agents. The differences in affinity of Cu(II) and Zn(II) complexes with these complexones result from the kind of functional groups of the chelating ion exchangers, such as thiourea, aminomethylphosphonate, iminodiacetate, and polyamine groups as well as from the pH value. The quantitative removal of studied heavy metal complexes using chelating ion exchangers is achieved in the case when resins compete successfully for the heavy metal ions against these chelators.Key words: chelating resins, heavy metals, EDTA, NTA.

The Preparation of TCAS-Loaded Resin and its Adsorption Property to Pb2+ Ion

2011 ◽  
Vol 396-398 ◽  
pp. 421-424
Author(s):  
Xiao Jun Hu ◽  
Pin Zhang ◽  
Yu Shuang Li
Keyword(s):  
Metal Ion ◽  
High Selectivity ◽  
Exchange Resin ◽  
Ph Value ◽  
Removal Rate ◽  
Adsorption Property ◽  
Maximum Adsorption Capacity ◽  
Adsorption Ability ◽  
Ph Values ◽  
Loaded Resin

A adsorbent for cadmium has been prepared by loading an anion-exchange resin with a novel supramolecular compound named thiacalix[4]arenetetrasulfonate (TCAS). The adsorption properties of Pb2+on TCAS-loaded resin had been studied and the effects of varying temperature, pH value, adsorption time and initial concentration. Batch extraction studies had revealed a high adsorption ability of the TCAS-loaded resin toward this heavy metal ion with high selectivity. The maximum adsorption capacity of the TCAS-loaded resin toward Pb2+ was 26.32 mg•g-1. The removal rate of Pb2+in water was up to 99% after 40min at 20°C when a 50mL aqueous solution of Pb2+(10 mg•L-1) was adsorbed by 0.5g TCAS-loaded resin. The removal percentage steadily retained above 99% when the pH values were in the range of 4 to 7. The adsorption isotherm of the TCAS-loaded resin to Pb2+ions fits well to linear form of Langmuir sorption equation.

Impact of pH Value and Temperature on Cement-Based Materials Adsorbing Heavy Metal Ions

2016 ◽  
Vol 847 ◽  
pp. 265-271
Author(s):  
Ya Li Wang ◽  
Su Ping Cui ◽  
Xi Kui Xu ◽  
Ming Zhang Lan
Keyword(s):  
Heavy Metal ◽  
Metal Ions ◽  
Heavy Metal Ions ◽  
Ph Value ◽  
Micro Structure ◽  
Ph Values ◽  
Isomorphous Replacement ◽  
Cement Based Materials ◽  
Double Decomposition ◽  
The Impact

The development of the city traffic and its increasing traffic flux are the signs of the development of the society, but causing a serious pollution on the city's ecological environment. Cement hydration reactions are needed to generate Ca (OH)2, C-S-H gel, and AFt, as well as other hydrated products. Meanwhile, heavy metal ions are contained and fixed in a cement paste under physical encapsulation, absorption, isomorphous replacement, and double decomposition. This paper mainly discusses the impact of hydration environment on the adsorption law of materials adsorbing heavy metal ions and the adsorption mechanism under different pH values and temperatures, analyzing specific reasons from the perspective of micro-structure. Through the analysis it can be seen that, in addition to zinc ions, the cement-based materials’ capacity of adsorbing heavy metal ions increases as the pH value and the temperature increase. Micro-structure analysis shows that cement-based materials’ main adsorption methods are different when pH values are different.

Synthesis of Graft Copolymer of Starch-Acrylamid-Propylene Hydroxamic Acid and Capability of Trapping Pb2+

2014 ◽  
Vol 1015 ◽  
pp. 369-372
Author(s):  
Chang You Song ◽  
Ai Bing Wu
Keyword(s):  
Heavy Metal ◽  
Reaction Time ◽  
Emulsion Polymerization ◽  
Graft Copolymer ◽  
Metal Ion ◽  
Hydroxamic Acid ◽  
Ph Value ◽  
Removal Rate ◽  
Heavy Metal Ion ◽  
Optimum Conditions

In this paper, graft copolymer of starch-acrylamid-propylene hydroxamic acid was synthesized by inverse emulsion polymerization. Effects of the dosage of the graft copolymer, pH value and reaction time on the capability of trapping heavy metal ion Pb2+ were investigated. The results showed that the optimum conditions for treating lead-containing wastewater were: pH=7-9, reaction time≧30min , the dosage of polymeric ferric sulfate and graft copolymer in wastewater were 10mg·L-1 and 250-300mg·L-1, respectively. The Pb2+ removal rate is not less than 99.8% and meanwhile the copolymer possess good removal performance of turbidity.

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