Investigation of the usage potential of calcium alginate beads functionalized with sodium dodecyl sulfate for wastewater treatment contaminated with waste motor oil

Abstract

In this study, calcium alginate (Ca-Alg) beads, an inexpensive, easily available, biodegradable material, were activated with anionic surfactant and used for the treatment of wastewater contaminated with waste motor oil. First, polyethyleneimine (PEI) was used to bind sodium dodecyl sulfate (SDS) onto the Ca-Alg beads' surface. Three different SDS concentrations (25, 50, & 100 mg/L) were prepared and treated with Ca-Alg beads for 1, 2, 4, 6, and 24 h. SDS binding yield reached equilibrium at the end of the 24 h, and the binding efficiencies of 25, 50, and 100 mg SDS/L were determined 84%, 72%, and 48%, respectively. The effect of pH between 2 and 10 was also investigated on oil adsorption. Maximum adsorption efficiency (77%) was obtained in the range of pH 6-8. After determining the optimum pH value for oil adsorption, the effect of beads amount (2.5-30 g/L) was also investigated on oil removal efficiency. When the amount of beads increased from 2.5 to 30 g/L, the oil adsorption efficiency increased from 77% to 95%. It was also observed that the oil adsorption efficiency increased when the size of the beads decreased from 4 to 1 mm. For the kinetic calculation, three different concentrations (250, 500, &1000 mg/L) of oily solution were prepared, and oil adsorption was investigated versus time. The kinetic studies for the adsorption of the oily solution using SDS functionalized Ca-Alg beads showed the second-order kinetics. When the initial oil concentration increased from 250 to 1000 mg/L, the amount of adsorbed oil molecules increased from 8.34 to 22.12 mg/g. Langmuir and Freundlich isotherm models were used to explain the relationship between adsorbent and adsorbate, and Langmuir isotherm was the most suitable model because of its high regression coefficient (r 2 ) value. Column studies were also carried out, and it was concluded that the proposed adsorbent can be used effectively in the treatment of oily wastewater. Practitioner points• Although there are numerous adsorption studies and studies on the use of alginate beads in various fields in the literature, its use in oil treatment has not been found to our knowledge.• The study aims to produce a selective adsorbent for the removal of oil from water by functionalizing the surface of the alginate beads with active agents.

The treatment of oily wastewater by thermo‐responsive calcium alginate capsules immobilized Pseudomonas aeruginosa

“…Compared with group c, the fermentation effect of thermo‐responsive CA capsule immobilized bacteria in group d was somewhat preferable. The thermo‐responsive property provided a beneficial enhancement to bacterial fermentation, and thermo‐responsive CA capsules immobilized bacteria exhibited an excellent ability to treat oil slick in water bodies under air ventilation (Bilici et al, 2021; Bagheri Lotfabad et al, 2017). This significantly improved the fermentation efficiency of the bacteria and introduced a new method for the rapid treatment of oil slicks.…”

Use of welding powder as a low‐cost adsorbent for waste motor oil removal

“…The properties of WMO are given in a previous study. [15] Total base number (TBN): 8.16 mg KOH g -1 ; density (15…”

“…The properties of WMO are given in a previous study. [ 15 ] Total base number (TBN): 8.16 mg KOH g –1 ; density (15°C): 0.893 g mL –1 ; kinetic viscosity at 40°C and 100°C: 162 and 19 cSt, respectively; flash point: 246°C; pour point: −27°C.…”

“…The highest removal effectiveness (77%) was observed in the pH range of 6-8. [15] Welding powder represents the highest percentage of solid waste generated in iron and steel manufacturing, reaching 70%-80%. [16] Recycling welding powder saves energy for the factory and assists to decrease trash and disposal costs, which has environmental and economic benefits.…”