الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Co-conditioning and dewaterability enhancing behaviors of aluminum-based sludge
were investigated using alternative conditioner (natural biopolymer-magnetite/H2O2) as a
Fenton conditioner. Firstly, natural biopolymer/magnetite (CSP@Fe3O4) were prepared in
various ratios and the samples labeled as (CSP@Fe3O4-(1:1); CSP@Fe3O4-(1:3) and
CSP@Fe3O4-(2:1). Focuses were placed on factors influencing such novel Fenton conditioner.
Capillary suction time (CST) was utilized to assess sludge dewaterability. Experiments have
exhibited that significant development of alum sludge dewaterability could be attained at
minimum reaction time and using low concentrations of the applied catalyst, i.e. natural
biopolymer/magnetite and H2O2. It was found that sludge conditioning and dewaterability
became better with increasing both reagents concentrations. A Box-Behnken experimental
design based on the response surface methodology (RSM) was investigated to explore the
optimum of the influencing variables, i.e. catalyst (NBP-M) concentration, H2O2 loading and
pH. The optimized values for NBP-M, H2O2, and pH are 46 and 380 mg/L, respectively at pH
3.0, at which the CST reduction efficiency of 58 ± 3% can be attained, this approved with that
predicted by an established polynomial model in the current investigation. Alum sludge is
subjected to polycationic polysaccharide-magnetic catalyst as a catalyst based Fenton oxidation
treatment and its influence and mechanism on sludge dewatering were investigated in the
present work. The results compared with the commercial conditioners such as polyelectrolytes,
which results in only 37% CST reduction. In comparison with chemical flocculants, the
conditioning process based Fenton’s reaction is ecofriendly since it uses both chitosan and
magnetite substances that are environmentally benign materials. Also, the system is oxidizing
the high proportion of materials in the sludge. Also, elevating temperature of the sludge showed
a negative effect in CST enhancement compared to the room temperature. Further analysis
showed that the change of the zeta potential (ζ-potential) of the sludge is changed to the more
positive values and the surface morphology attained bigger flocs than of the raw sludge.
Furthermore, “Circular Economy” concept is leading the scientist to convert the drinking water
treatment plant by-product that is based on aluminum waste into a valorized material for
wastewater treatment. Alum sludge from a local waterworks plant in Egypt is collected and
introduced for dewatering with chitosan-coated magnetic nanoparticles. Chitosan augmented with magnetite nanoparticles that is prepared by simple coprecipitation simple route with a mixing ratios (1:1), (2:1) and (3:1) of chitosan and magnetite
nanoparticles labeled as ChMNs catalyst. ChMNs that showed beneficially enhance alum
sludge conditioning and dewaterability. The characteristics of the AS-ChMNs sample were
investigated using Fourier transform infrared spectroscopy (FTIR) and scanning electron
microscopy (SEM). Response surface mythological analysis has been applied to optimize the
operational parameters and highlighting a savings in chemicals used and showed an increment
in the process efficiency. The conditioned aluminum based sludge strategy can be viewed as a
“win-win” strategy for supposing it for eliminating another waste such as wastewater treatment
industry.