-
An Alternative Arrangement for the Alum Sludge Management: Minimising Waste with Low-Cost Solar Techniques
Maha A. Tony,
Aghareed M. Tayeb,
Yaqian Zhao
Issue:
Volume 4, Issue 2, March 2016
Pages:
30-37
Received:
22 January 2016
Accepted:
30 January 2016
Published:
31 March 2016
Abstract: Alum sludge produced from the drinking water treatment plants was used to investigate the improvement capabilities in its dewatering properties. The sludge was passed through a laboratory solar still towards reducing the sludge volume during the dewatering process. A number of parameters describing the distillate and the sludge were measured at the end of each experiment in order to determine the process behaviour under conditions of relatively high solar radiation which is reached to 1014 W/m2 and temperature levels which reaches inside the still to a maximum of 87°C. Conventional chemical conditioners in augmentation with the solar dewatering such as polyelectrolyte, and advanced conditioner like photo-Fenton’s reagent were used in the sludge conditioning studies. Experimental results indicated that 10 mg/L of anionic polyelectrolyte conditioner enhance the dewateraibility in the terms of SRF reduction to 97%. However, it reached to 78% when the Fenton’s reagent is added. It is realized that dewatering is accelerated when the polymer is added compared to that of Fenton’s reagent conditioning; Fenton’s reagent offers a more environmentally safe option. Moreover, the volume of distillate collected is nearly a double fold increase in the case of the conditioning with the Fenton’s reagent rather than that for the organic polymer. In addition, the turbidity of the supernatant are: 3.4, 2.7 and 247 NTU for polyelectrolyte, Fenton’s reagent treatment and for the raw sludge, respectively. Furthermore, the optimum influencing variables of Fenton’s reagent is evaluated by applying Box-Behnken experimental design based on the response surface methodology (RSM), i.e. Fe2+, H2O2 and pH are 50 mg/L, 600 mg/l and 8.5, respectively.
Abstract: Alum sludge produced from the drinking water treatment plants was used to investigate the improvement capabilities in its dewatering properties. The sludge was passed through a laboratory solar still towards reducing the sludge volume during the dewatering process. A number of parameters describing the distillate and the sludge were measured at the...
Show More
-
Palladium(II)-Catalyzed Oxidation of Pyrimidine Derivative by Hexacyanoferrate(III) in Aqueous Alkaline Medium: A Kinetic Study
Ahmed Fawzy,
Ishaq Zaafarany,
Fahd Turkistani,
Jabir Alfahemi,
Moataz Morad
Issue:
Volume 4, Issue 2, March 2016
Pages:
38-45
Received:
10 March 2016
Accepted:
18 March 2016
Published:
31 March 2016
Abstract: The of kinetics of oxidation of a pyrimidine derivative, N,N-dimethyl-N’-(pyrimidin-2-yl) formamidine (Pym-F), by hexacyanoferrate(III) (HCF) was studied in aqueous alkaline medium in the presence of palladium(II) catalyst. The reaction did not proceed in the absence of Pd(II) catalyst. The progress of the catalyzed reaction was followed spectrophotometrically. The reaction showed a first order kinetics in both [HCF] and [Pd(II)], and less than unit orders with respect to both [Pym-F] and [OH-]. Increasing ionic strength and dielectric constant of the medium increased the reaction rate. A mechanistic scheme for the catalyzed oxidation reaction has been proposed. The final oxidation products are identified as 2-aminopyrimidine, dimethylamine and carbon dioxide. The rate law expression associated with the reaction mechanism is derived and the reaction constants involved in the different steps of the mechanism are calculated. The activation parameters with respect to the rate-determining step have been computed and discussed.
Abstract: The of kinetics of oxidation of a pyrimidine derivative, N,N-dimethyl-N’-(pyrimidin-2-yl) formamidine (Pym-F), by hexacyanoferrate(III) (HCF) was studied in aqueous alkaline medium in the presence of palladium(II) catalyst. The reaction did not proceed in the absence of Pd(II) catalyst. The progress of the catalyzed reaction was followed spectropho...
Show More
-
Generalized Model of Adsorption Equilibria Prediction for CO2 on Carbonaceous Adsorbents
Kuerbanjiang Nuermaiti,
Ming Li
Issue:
Volume 4, Issue 2, March 2016
Pages:
46-51
Received:
8 April 2016
Published:
9 April 2016
Abstract: The carbon molecular sieve CMS-200 and activated carbon Yigao-A have been adopted as adsorbents for the study of CO2 adsorption capture. The pore size distributions of both adsorbents were characterized by the modified H-K method. Adsorption isotherms of CO2 on the carbon molecular sieve CMS-200 and activated carbon Yigao-A were measured by the gravimetric method (Hiden, IGA-001) in the temperature region of 253.15-393.15 K and pressure region of 0-2 MPa. The Henry’s law constants of adsorption equilibria for CO2 were estimated using the Virial equation. The Ruthven’s generalized model was applied to analyze the experimental data on the basis of the values of the Henry’s law constants. The investigation demonstrates that the Ruthven’s generalized model not only is useful to describe the adsorption equilibria for CO2 on non-porous homogeneous carbonaceous adsorbents in the subcritical region, but also is reliable to predict the adsorption equilibrium data for CO2 on carbonaceous adsorbents with the uniform pore size distribution and the wide pore size distribution from the subcritical region to the supercritical region.
Abstract: The carbon molecular sieve CMS-200 and activated carbon Yigao-A have been adopted as adsorbents for the study of CO2 adsorption capture. The pore size distributions of both adsorbents were characterized by the modified H-K method. Adsorption isotherms of CO2 on the carbon molecular sieve CMS-200 and activated carbon Yigao-A were measured by the gra...
Show More
-
Progress on Collection, Treatment and Utilization of Solid Waste
Shang Shuyong,
Mei Li,
Zhang Yudie,
Huang Fei,
Wang Bing,
Li Weiyi
Issue:
Volume 4, Issue 2, March 2016
Pages:
52-56
Received:
3 May 2016
Published:
19 May 2016
Abstract: With more and more serious impact on the environment by solid waste, the collection, treatment and utilization of solid waste have become the research focus in the current. This article mainly generalizes the collection ways and treatment methods for the living garbage, industrial waste and agricultural waste. The resource utilization techniques of solid wasteincluding separation technology, incineration and pyrolytictechniques, biological treatment technology, energy recovery via RDF and incineration power generationare analyzed and discussed in detail. The results will provide some proper proposals for handling and reusing solid waste effectively and contribute to the social sustainable development, the low carbon economy and the eco-development.
Abstract: With more and more serious impact on the environment by solid waste, the collection, treatment and utilization of solid waste have become the research focus in the current. This article mainly generalizes the collection ways and treatment methods for the living garbage, industrial waste and agricultural waste. The resource utilization techniques of...
Show More
-
The Study to Investigate Growth Rate of Metal Nanowires into Anodic Alumina Oxide Arrays via Electrodeposition
Tahir Mehmood,
Aiman Mukhtar,
Babar Khan,
Kaiming Wu
Issue:
Volume 4, Issue 2, March 2016
Pages:
57-61
Received:
17 May 2016
Published:
19 May 2016
Abstract: To understand the growth mechanism of electrodeposited Fe, Ni and Co, we have studied the effect of workfunction on the metal nanowire growth by SEM and Potentiostat. We found that the current density for deposition of Fe nanowires is higher than of Ni and Co nanowires under the same fixed potential, overpotential, pH, concentration of metal ions and temperature. Using the electrons tunneling theory, we have argued that the current density of the metals depends on the workfunction and width of double layer. The current density increases with decreasing the length of double layer. The current density of metal with a smaller workfunction can be higher than that of metal with a larger workfunction.
Abstract: To understand the growth mechanism of electrodeposited Fe, Ni and Co, we have studied the effect of workfunction on the metal nanowire growth by SEM and Potentiostat. We found that the current density for deposition of Fe nanowires is higher than of Ni and Co nanowires under the same fixed potential, overpotential, pH, concentration of metal ions a...
Show More
-
Converting Volatile Organic Compounds to CO2 and Water
Issue:
Volume 4, Issue 2, March 2016
Pages:
62-67
Received:
6 June 2016
Published:
7 June 2016
Abstract: This paper discusses a novel method to clean VOC from any sources. Photocatalysis surpasses any other technologies in air purification for absorption of volatile organic compounds. A key component is the use of ultraviolet light to activate a photo-catalysis process that can also disinfect microorganisms including bacteria, viruses, moulds and even infectious diseases. The by-products of the photocatalytic process is only carbon dioxide and water. Results as tested by the Chinese government agency for its VOC removal efficacy at several factories is most encouraging. In conclusion, we have found a technology that can help clean the increasing air pollution in China to improve public health.
Abstract: This paper discusses a novel method to clean VOC from any sources. Photocatalysis surpasses any other technologies in air purification for absorption of volatile organic compounds. A key component is the use of ultraviolet light to activate a photo-catalysis process that can also disinfect microorganisms including bacteria, viruses, moulds and even...
Show More
