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Showing 5 results for Cyanide
Efficiency Compare of Both Sonochemical and Photosonochemical Technologies for Cyanide Removal fromAqueous Solutions
R Shokuhi, A.h Mahvi, Z Bonyadi,
Volume 3, Issue 2 (7-2010)
Abstract

Backgrounds and Objectives: Cyanide is a species of high toxicity that found mostly in industrial effluents such as electroplating, metal mining, metallurgy and metal cleaning processes. Intrance of it to Existence enviroment contains very health hazardous. Purpose of this study, efficiency compare of both sonochemical and photosonochemical technologies for cyanide removal from aqueous solutions.
Materials and Methods: in this study, it has been used from a productive set of 500w power ultresound waves in of two frequencies 35 kHz and 130 kHz and a 125 W low pressure mercury lamp. Experiments were performed at initial cyanide concentrations varying from 2.5 to 75 mg/L. in this study, The effects of parameters such as pH, time and initial cyanide concentration on the sonochemical and photosonic degradation have been studied.
Results:The results of the study showed that the maximom removal efficiency of cyanide had been achieved sonochemical technology was 71% while it was 74% by photosonic at frequency of 130 kHz, at time of 90 min, pH of 11 and initial cyanide concentration of 2.5 mg/l.
Conclusion: The results of the study showed that efficiency of photosonic process is more than for sonochemical cyanide removal fromaqueous solutions.Also efficiency of cyanide removal has direct relationship with pH, frequeny and time ,and it has reverse relationship with cyanide concentration for both processes.


Removal of Cyanide from Aquatic Solution by Using of  Iron and Copper Powder: Equilibrium and Kinetic Study
M Shirzad Siboni, M.r Samarghandi, M Farrokhi, H Piri Dogahe, M Zarrabi,
Volume 4, Issue 3 (10-2011)
Abstract

Background and Objectives: Industrial wastewater included the cyanide is one of the important sources of environmental pollution which founded in Industrial wastewater which are harmful for human health and environment. Therefore, the purpose of this research that was fundamental designed is investigation of Removal of cyanide from aquatic solution by using of iron and copper powder in experimental scale.
Material and Methods: At first, pilot was designed. Then, acquired pH optimum equal to 2,7 for copper and iron by variation pH= (2,4,6,8,12) and constant other parameters. The effect of initial cyanide concentration (40,60,80 mg/l), initial iron and copper dosage (0.08-1 g/100CC) and contact time (15-12 min) studied at the constant of optimum pH. 
Results: The result showed removal efficiency Increased from 46.6% to 90.56% and 31% to 93.78% for copper and iron by increasing of contact time from 15to 120 minute in constant conditions, respectively. Also result showed Removal efficiency decreased and increased by increasing initial cyanide concentration and initial iron and copper dosage. The results showed equilibrium data were explained acceptably by Langmuir isotherms and kinetic parameters were obtained by application of Langmuir&Hinshelwood equation.
Conclusion: The results showed that removal of cyanide can be quick and effective done by iron and copper in experimental scale.


Survey of Efficiency of Electrochemical Treatment in Cyanid Removal from Industrial Wastewatersrs
Z Kheradpisheh, H Movahedian Atar, M Salehii Najafabadi,
Volume 4, Issue 4 (3-2012)
Abstract

Background and Objectives: Cyanide is a highly toxic compound which is Normally found in numerous industries, such as electroplating wastewater. Release of this compounds in to the Enviroment has a lot health hazards.The Purpose of this study is to Determine the efficiency of electrochemical oxidation method for Cyanide removal from industrial wastewaters

Materials and Methods: This study conducted in a pilot system experimentally .In this study the effect of pH, voltage and operation time on total cyanide removal from industrial wastewaters by Electrochemical Oxidation was investigated by applying a Stainless Steel as a Anode and copper as a cathode .

Results: The average percentage removal of cyanide was about 88 with SD=2.43. The optimal condition obtained at voltage of 9V and pH=13 and The operation time of 90 minutes.The volume of sludge which formed in this condition was  about 20 percent of a one liter pilot reactor.

Conclusion: the results statistically confirmed the significant relationship between

input and cyanide concentration removal efficiency (p< 0.05), and confirmed  The this confirmed The  relation between cyanide & cyanat oxidation and hydroxyl ions consumption 1:2.( L.Szpyruowicz). therefore the best pH is 12.5-13.5 by Considering the need  of alkaline environment to remove cyanide.

The Study of Fenton Performance in Removal of  Cyanide from Aqueous Solution
Somayeh Golbaz, Ahmad Jonidi Jafari, Roshanak Rezaei Kalantari,
Volume 5, Issue 4 (2-2013)
Abstract
MicrosoftInternetExplorer4 Background and Objectives: Cyanide is a toxic pollutant existing in the various industrial effluents such as iron and steel, coal mining, non-ferrous metals manufacturing and metal plating. Its presence in water resources and wastewater, as serious hazardous substances leads to undesirable effects on both the environment and human. Thus, its concentration control is essential for human health. The main goal of this study was to evaluate Fenton process efficiency in cyanide removal from aqueous solution.
Materials and Methods: This is an experimental study Conducted at Lab scale in a batch system. We investigated effect of different variables including pH, mole ratio of Fe2+/ H2O2, contact time, and initial concentration of cyanide. Data were analyzed using Excel software.
Results: We found that cyanide with initial concentrations of 0.4 mM/L was reduced by 92 %. This removal result was related to oxidizing agent of hydroxyl radicals under optimum conditions including pH = 4, molar ratio Fe2+/ H2O2= 0.046 (Fe2+=0.27 mM/L) after 6o min reaction time. An increase in reaction time was not improved cyanide removal efficiency. Moreover, the Fenton process efficiency in cyanide removal decreased from 92 to 60 %, by increasing the initial cyanide concentration from 0.4 to 0.6 mM/L.
Conclusion: It can be concluded that Fenton oxidation Process can be considered as a suitable alternative for cyanide removal to achieve environmental standards.


Phytoremediation of the soils contaminated with cyanide by Vetiveria zizanioides
Ar Mansoorian, A Vaziri, Mr Zamani, F Heidaryan Naeini,
Volume 10, Issue 3 (12-2017)
Abstract
Background and Objective: In the field of environmental risk assessment, Cyanide is one of the most important pollutants of water, soil and air that has an important impact on the ecosystem and environment of the contaminated area. Therefore, the present study aimed to prove the biological effectiveness of Vetiveria zizanioides in phytoremediation of soils contaminated with cyanide.
Materials and Methods: This research study was conducted on a gold mine wastewater. The dried effluent samples amended with soil with various cyanide concentrations. Seven treatments with different concentrations of cyanide were obtained (mean cyanide content in G soil, 14.77 mg/kg, F soil, 10.13 mg/kg, E soil, mg/kg 8.09, D soil, mg/kg 7.53, C soil, 3.32 mg/kg, B soil, 2.52 mg/kg and A soil without cyanide (as control). After two months, the amount of cyanide in the soil, roots and leaves of the plant, as well as the total protein and proline content, and the number and length of the leaves of the plant were measured and then statistically evaluated by SPSS15 Tukey and t Paired Samples T Tests.
Results: The results of this study showed that the increase of cyanide had a significant effect on the amount of proline (proline in the plant increased), total protein (in the plant increased), number of leaves (decrease in number) and the length (length reduction) of the leaves of the vetiver. The amount of cyanide in the leaves and roots of the plant was increased. Cyanide content was decreased in the different treatments. Cyanide content was decreased in G 50.93%, F 38.20%, E 27.19%, D 38.37%, C 17.77% and B 16.66%.
Conclusion: The results indicated that increase of the amount of cyanide in soil resulted in observational changes in the morphological and biochemical characteristics of the plant. However, Vetiveria zizanioides exhibited very high resistance to soil cyanide and the planting of vetiver in highly contaminated soils can lead to a reduction of cyanide up to 50 percent. Vetiveria zizanioides had higher resistance to cyanide and showed better phytoremediation than the other plants.
 

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