Page 143 - AJWEP-22-6

Charcoal-adsorption of antibiotic fermentation broth

3. Results and discussion Table 2. Physicochemical properties of the
fermentation broth effluent
3.1. Physicochemical properties Parameter Value
The physicochemical properties of the fermentation Color Creamy yellow
broth, containing organic materials and cells of
S. pristinaespiralis, were evaluated (Table 2). The pH 6.8±0.11
broth was semi-transparent with a creamy-yellow color. Total solids (g/L) 6.5±0.20
The total solids and sugars were 6.5 g/L and 3.84 g/L, Sugars (g/L) 3.8±0.15
respectively, while the concentrations of K , Na , Mg , Calcium ion (ppm) 560±5.46
2+
+
+
and Ca were 100, 150, 360, and 560 ppm, respectively. Sodium ion (ppm) 360±4.89
2+
Potassium ion (ppm) 150±2.33
3.2. Effects of AC dose and temperature on organic
materials Magnesium ion (ppm) 100±3.12
Biopharmaceutical wastewater typically exhibits Zinc (II) ion (ppm) 3.0±0.25
high BOD and COD levels due to the presence of Copper (II) ion (ppm) 0.1±0.001
microorganisms and organic compounds. This section Chromium (II) ion 0.1±0.001
discusses the application of different concentrations of (ppm)
AC at varying temperatures to reduce COD and BOD
in pristinamycin fermentation broth. The pH of the
fermentation broth was 6.8. However, no significant
change was observed in the pH of treated effluents
following AC treatment (data not shown). Neither
increasing the AC dosage nor temperature significantly
affected pH values. This may be attributed to the use of
relatively low carbon concentrations, with the maximum
being 30 mg/L.

3.2.1. Effects of AC dose and temperature on COD
The application of 30 mg/L AC at 25°C to antibiotic
fermentation broth reduced COD from approximately
172,000 mg/L to 82,300 mg/L (Figure 1). COD
reduction was significantly higher (p<0.05) at 30 mg/L
than at 10 mg/L. Treatments with 10 mg/L and 20 mg/L
AC did not yield significant reductions in COD relative Figure 1. Effect of activated carbon dosage and
to the control group at 25°C (p˃0.05). However, temperature on COD reduction in the pristinamycin
increasing the treatment temperature to 50°C and fermentation broth. Dosages of 10, 20, and 30 mg/L
75°C for the 20 mg/L treatment led to significant COD were evaluated, with the control receiving no
reductions (p<0.05), yielding residual COD values of activated carbon treatment.
100,000 mg/L and 68,100 mg/L, respectively. Abbreviation: COD: Chemical oxygen demand.
No statistically significant difference (p>0.05) was
observed between the 30 mg/L and 20 mg/L treatments toward the liquid phase, and (iii) enhanced desorption
at 75°C, which achieved maximum COD reductions of in exothermic reactions.
66% and 62%, respectively. The reduced adsorption Increasing the AC dosage resulted in greater COD
at elevated temperatures is primarily due to weak removal efficiency (Figure 1). Mullai and Rajesh
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interactions between the active sites of the adsorbent observed a similar trend, attributing the enhanced
and the adsorbate molecules. 11,24 Farhadpour and Bono efficiency to the abundant active sites present on
25
reported that acid extraction by granular AC and amine the charcoal surface, which facilitate the removal
groups is exothermic and decreases with increasing of organic substances from fermentation broth.
15
temperature due to: (i) decreased adsorption affinity Umrantezcanun et al. investigated the effects of
12
for adsorbate molecules, (ii) a shift in equilibrium adsorbent dose, pH, temperature, initial antibiotic

Volume 22 Issue 6 (2025) 137 doi: 10.36922/AJWEP025240198