Degradation of hydroxypropyl guar gum at wide pH range by a heterogeneous Fenton-like process using bentonite-supported Cu(0)

Abstract

To seek for efficient Fenton-like oxidation processing for treatment of waste fracturing fluid containing hydroxypropyl guar gum (HPGG), in heterogeneous reaction, five bentonite-supported zero-valent metal catalysts were prepared by liquid-phase reduction. The results showed that the bentonite-supported zero-valent copper exhibited best catalytic performance, attributed to the high dispersion of active sites of zero-valent copper. The effects of the most relevant operating factors (H2O2 concentration, catalyst dosage, temperature and pH) were evaluated in detail. Moreover, the chemical oxygen demand removal rate of HPGG can achieve 76% when the reaction time was selected at 45 min under optimal experimental conditions. The stability evaluation showed that the catalytic performance was almost unaffected after the catalyst was recycled and used once more showing the good stability of the bentonite-supported zero-valent copper in the application process.

Fenton-like oxidation of Hydroxypropyl guar gum catalysed by Cu(II) complex at high pH

“…As we all know, conventional Fenton oxidation needs to adjust the pH to about 3 first to ensure the activity of the catalyst. The fracturing fluid is usually alkaline [26], so it requires a lot of cost to pre-treat the wastewater. This paper evaluated the removal effect of the prepared Cu(II) complex catalyzed by H2O2 to degrade HPGG under high pH conditions.…”

Synthesis of Porous MgAl-LDH on a Micelle Template and Its Application for Efficient Treatment of Oilfield Wastewater

“…During the oil recovery process of deep shale, however, a large amount of highly concentrated and difficult-to-degrade drilling fluid wastewater containing sulfonated lignite macromolecules will be generated, causing deterioration of ecosystems as well as water quality and easily reacting with chlorine used in water treatment to produce carcinogens [ 6 , 7 , 8 , 9 , 10 , 11 ]. There are many methods to treat drilling wastewater, such as Fenton oxidation, the gravity separation method, the membrane separation method, the flocculation method, the salting-out method, the activated sludge method, the biological filter method, and peroxydisulfate oxidation [ 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 ]. However, most of them have shortcomings such as non-renewable raw materials, high operating costs, and incomplete treatment of pollutants.…”

Hollow Nanospheres Organized by Ultra-Small CuFe2O4/C Subunits with Efficient Photo-Fenton-like Performance for Antibiotic Degradation and Cr(VI) Reduction

“…Nevertheless, the traditional homogenous Fenton processes include obvious and inevitable shortcomings, such as production of iron containing sludge, low pH (pH < 3.0), large amount of H 2 O 2 , requirement for secondary treatment and difficult regeneration of the catalyst, which have greatly restricted their wide applications. To solve this problem, a "Fenton-like" reaction, which can surmount the above-mentioned adverse conditions as, for example, the reduction of H 2 O 2 by modifying the process going towards the photo-Fenton reaction, has been considered as one of the most effective methods [26][27][28][29][30][31][32][33][34]. Therefore, the key point is to exploit suitable semiconducting, heterogeneous and Fenton-like catalysts with a wide pH range, high reusability, excellent activity and good stability.…”