Enas Sameer Alkhawaja*
| Hayder Mohammed Abdul-Hameed
© 2025 The authors. This article is published by IIETA and is licensed under the CC BY 4.0 license (http://creativecommons.org/licenses/by/4.0/).
OPEN ACCESS
Hospital wastewater contains a variety of organic, inorganic, and heavy metal contaminants. In this study, wastewater samples were collected from Al-Sader Medical City Hospital in Al-Najaf, Iraq, and the removal efficiency of pollutants was evaluated using flash graphene (FG) as an adsorbent. Flash graphene was synthesized from Iraqi orange peel using a novel carbon-based method known as flash Joule heating (FJH). The data obtained demonstrate the presence and subsequent reduction of various contaminants in hospital wastewater—such as total suspended solids (TSS), phosphate (PO₄³⁻), pH, total dissolved solids (TDS), dissolved oxygen (DO), total organic carbon (TOC), nitrate (NO₃⁻), chloride (Cl⁻), cobalt (Co), copper (Cu), and chemical oxygen demand (COD)—after treatment with flash graphene. Based on biological and chemical standards, the concentrations of heavy metals such as copper and cobalt exceeded the permissible limits set by Iraqi water quality regulations. In addition, elevated levels of total hardness and chloride were also observed, exceeding national water quality standards. These findings suggest that hospital wastewater is a significant source of environmental pollution and should be carefully considered when formulating strategies to assess environmental and public health risks. Flash graphene, characterized by an average pore diameter of 18.534 nm and a specific surface area of 11.168 m²/g, proved to be an effective adsorbent for removing organic pollutants (BOD, COD, TOC), inorganic contaminants (TDS, DO, PO₄³⁻, NO₃⁻, Cl⁻, Co, Cu), and mixed pollutants such as TSS. This study proposes that adsorption using flash graphene could serve as a more cost-effective alternative to conventional hospital wastewater treatment systems. The volume and composition of toxic substances and liquid waste generated by hospital operations pose significant risks to both human health and the environment. In many developing countries, untreated hospital wastewater is often discharged directly into the environment, including rivers and other water bodies, which exacerbates environmental pollution.
hospital wastewater, flash graphene, organic, inorganic
Wastewater represents one of the most significant threats to aquatic ecosystems. According to the World Health Organization, health-related pollution arises from the activities of healthcare centers, hospitals, medical laboratories, and pharmacies [1]. Liquid medical waste contains pharmaceutical products and materials, organic and inorganic chemicals, and toxic substances [2].
In recent decades, the volume and complexity of pollutants in hospital wastewater have increased due to the expansion of medical services, rising patient numbers, and inadequate waste treatment and disposal practices [3]. Pollution occurs when pollutants are discharged into rivers, such as physical, chemical, and biological pollutants resulting from industrial, sanitary, or domestic wastewater, and the presence of these chemicals impacts the vitality of living organisms [4]. Water pollution is one of the most serious threats to the health of all living organisms, including humans. Moreover, polluted water may contain heavy metals, dangerous and toxic compounds, and disease-causing organisms, making it unfit for drinking [5].
Suppose hospital waste is not properly treated through physical, chemical, and biological processes prior to discharge. In that case, it can severely contaminate lakes and other water bodies and contaminate the water upon reaching the riverbed. Additionally, the presence of heavy metals affects water quality [6].
Hospitals contribute to the progress of medical science and research and are vital to the well-being of humanity. By providing ongoing assistance to meet complex health problems, they contribute to health services [7]. Nevertheless, these operations are linked to the production of significant amounts of wastewater [8, 9]. Additionally, hospitals produce a substantial amount of biomedical waste (BMW) [10]. The hospital's size significantly impacts the waste management procedures, the services and facilities provided, and the kinds and amounts of Hospital wastewater (HWW) created.
Hospital wastewater (HWW) differs significantly from domestic wastewater, as it contains hazardous and potentially infectious substances. The wastewater released by radiology, diagnostic labs, surgical rooms, and infectious wards [11] includes radioactive elements, hazardous organic pollutants, harmful bacteria and viruses, and pharmaceutical substances, including psychiatric drugs, antibiotics, and other pharmaceutical compounds. The many harmful microorganisms found in HWW emphasize the possible risk to public health that HWW discharge to the receiving water poses [12, 13]. Therefore, to reduce the negative effects of hospital effluents on the environment, adequate treatment is essential [14]. The typical characteristics of HWW are highlighted in Table 1. Al-Sadr Teaching Hospital in Najaf is a major healthcare facility in the region. Environmental engineers have a daunting issue in managing the massive amounts of wastewater generated by the hospital's ever-increasing development of pharmaceutical and healthcare operations [7]. Generally speaking, HWW has higher concentrations of nitrogen, ammonia, chemical oxygen demand (COD), and biochemical oxygen demand (BOD) than home wastewater [13, 14].
COD is the number of oxygen equivalents used in a potent oxidant's chemical oxidation of organic matter. In contrast, the amount of oxygen microorganisms require to decompose organic matter in aerobic conditions at a specific temperature and time is known as BOD [15, 16]. Therefore, BOD can be defined as the wastewater's biodegradable portion, whereas COD measures both biodegradable and non-biodegradable organic molecules. The biodegradability index is the ratio of wastewater BOD to COD [16, 17]. Additionally, HWW has a lower biodegradability index than municipal wastewater, which makes it challenging for traditional biological systems to handle [13, 14, 18].
Many organic compounds present in HWW are highly toxic and possess very low drinking water equivalent limit (DWEL) values, a significant environmental concern [19].
Over the years, a variety of treatment technologies have been employed to treat HWW, including advanced oxidation processes like photocatalysis and the Fenton process, biological techniques like the adsorption-built wetlands (CWs), membrane bioreactors (MBR), moving bed bioreactors (MBBR), and activated sludge processes (ASP) [19]. In addition to its high susceptibility to disease outbreaks, hospital wastewater poses a serious risk to public health due to the complex pollution load it places on ecosystems and water supplies, due to the presence of pharmaceutically active compounds and other recalcitrant organic compounds [1].
This study provides insight into the occurrence, persistence, and removal of BOD, COD, total suspended solids (TSS), PO4, pH, TDS, DO, TOC, NO3, and Cu.
Graphene is a two-dimensional material composed of a single layer of sp²-hybridized carbon atoms arranged in a hexagonal lattice. Graphene has captivated scientists because of its distinct shape, chemical makeup, mechanical, electrical, and thermal characteristics, and enormous specific surface area [14].
Using two distinct online platforms, this study presents a novel technique that uses a short electrical pulse combined with a powerful radiation burst to transform several inexpensive carbon species into desired graphene flakes quickly. These resources include coal, petroleum coke, tires, charcoal, food scraps, carbon black, and other plastic waste. The entire process takes less than a second. The resulting product is referred to as FG [13, 14]. This technique uses FJH to rapidly create graphene from carbon-containing materials. The synthesis of FG does not require a furnace, solvents, reactive gases, or additional purification steps. If certain carbon sources are used, graphene can be produced from carbon for as little as $30/metric ton due to its low electric energy requirements and exceptional ease of scale production [14]. For various reasons, scientific efforts to use graphene as an adsorbent are still in their infancy in Iraq; nevertheless, the preparation time is the most significant [20]. Cost-effective graphite produced from fruit was used to create a new adsorbent [21].
2.1 Study area
The study was conducted at the University of Baghdad, College of Engineering, in the Environmental Engineering department /Iraq. The study samples were collected from Al-Sader Medical City Hospital, which is located in Najaf, Iraq, approximately 160 kilometers (99 miles) south of Baghdad. The hospital coordinates are Latitude 32.01789° N and Longitude 44.37256° E. One of the key healthcare institutions in the province was established in the 1980s. The hospital has a capacity of 597 beds, making it a cornerstone of medical services in the region, as shown in Figure 1.
(a) (b)
Figure 1. a) The city of Al-Najaf, Iraq, b) Al-Sader Medical City Hospital (sampling stations)
2.2 Adsorbent flash graphene
The FJH technique is an advanced and efficient method for synthesizing FG from carbon-based materials as an adsorbent. FJH is a new way to make a lot of high-quality FGS [22]. Flash graphene is sourced from orange peel activated carbon that is prepared by chemical and physical activation. For more details about the preparation process, see our previous work [23]. This method employs a quartz tube with two electrodes, where a rapid discharge of electric current, controlled by a mechanical relay, produces 1 gram of FG per batch. The process utilizes a two-capacitor bank of (470 µF per capacitor) charged by a 210 V direct current source, with a 460 × 2-volt voltage. It requires no additional purification steps, solvents, or reactive gases, making it cost-effective and environmentally friendly. Figure 2 shows the flash graphene synthesis process.
Figure 2. Flash graphene synthesis process
The FG characteristic is an average pore diameter of 18.534 nm and a specific surface area of 11.168 m²/g. It is suitable for various applications in water treatment, spectroscopy, environmental science, and materials engineering, addressing significant industrial and scientific demands through its surface, which contains hydrophilic functional groups. The rapid, cost-effective synthesis and superior physical and chemical properties make FG highly suitable for water and wastewater treatment, pollutant adsorption, nanomedicine, and advanced material science applications.
Given the current widespread discharge of industrial wastewater into the environment, it is strongly advised that cost-effective adsorbents be used for water treatment because they are not only affordable but also readily available locally, technically feasible, and engineeringly applicable [24].
2.3 Wastewater
Al-Sadeer Medical City Hospital is a general and teaching hospital that provides all kinds of physical and surgical services. The Iraqi Ministry of Health acquired it. The hospital operates a referral system at a rate of more than 2500 references per month. It is considered one of the most important hospitals in Al-Najaf, Iraq. The hospital has an old treatment plant for its own discharged wastewater. As wastewater was generated from different hospital departments, and the wastewater flow ranged from 70 to 78 L/h during the research period, the wastewater was discharged within the hospital sewage network connected to the sewer system.
The samples were taken periodically at a rate of 80 liters of wastewater from the final discharge point (main hole). As the research conducted an actual wastewater sample to achieve the realistic status of wastewater specification, the initial wastewater specifications varied according to the discharged wastewater specification at the sampling time. The samples were immediately transported after treatment to the service laboratory. This study aims to examine the wastewater treatment plant at the Al-Sadr Medical Teaching City Hospital in Al-Najaf and the consequences of hospital waste released from the facility. All of the locations under study had a pH of 8.2. The average values of TDS, DO, BOD5, COD, TOC, PO4, NO3, Cl, TSS, Co, and Cu were 1730, 5.3, 5.3, 40, 8, 3.518, 0.94, 480, 1050, 0.14, and 0.481 mg/L, respectively, as shown in Table 1.
Table 1. Initial concentration from the main hole in the hospital
|
Samples |
pH |
TDS |
DO |
BOD |
COD |
TOC % |
PO4 |
NO3 |
Cl |
TSS |
Co |
Cu |
|
Original |
8.2 |
1730 |
5.3 |
5.3 |
40 |
8 |
3.518 |
0.94 |
480 |
1050 |
0.14 |
0.481 |
The findings showed that the hospital's BOD5, COD, TSS, TDS, PO4, NO3, and CL concentrations exceeded the Iraqi reuse threshold, indicating that hospital wastewater needs treatment before municipal sewage disposal. A novel adsorbent was developed, utilizing cost-effective fruit-derived graphite [25]. The recent advances in graphene-based nano-carriers for drug delivery applications are a significant development in Nanomedicine [26].
2.4 Sample collection
Collecting samples of wastewater discharged from Al-Sader Medical City Hospital's main septic tank began in the summer of 2024 to evaluate its quality. Samples were collected between 12 p.m. and 2 p.m. at 10 to 25cm below the surface water in the collection basins. The sample was collected directly from a sewage water tank in Al-Sader Hospital in a 1-liter glass container and directly transported to the lab with an ice box container for laboratory chemical analysis in the field; the air temperature was 35℃, the water temperature was 27℃, and add for dissolve oxygen container (KI and MnSO4) reagent for fix the oxygen value and the COD and TOC sample, add H2SO4.
2.5 Batch
This experimental work was conducted to treat AL-Sadeer Medical City Hospital wastewater using Flash graphene, which was locally prepared for batch experiments to treat the hospital wastewater. The wastewater was taken from AL-Sadeer Medical City Hospital on Kufa Street in Najaf City, Iraq.
Batch experiments were carried out using conical flasks of 250 cm3 in size and filled with 100 cm3 of real medical wastewater from AL-Sadder Medical Hospital in AL-Najaf City in Iraq. Sixteen experiments were conducted for batches of heavy metals, and organic and inorganic removal from real medical wastewater was done. In these experiments, the effect of different parameters, such as contact time, pH, adsorbent dose, and agitation speed, was studied to determine the best conditions and to find equilibrium data for the treatment process.
Removal efficiency were examined through different adsorbent dosages (0.5, 1, 1.5, and 2) gm, different periods (15, 30, 60, 90, and 120) min, pH (5, 7.3, and 8.5), different agitation speed (100, 150, 200 and 250) rpm, and constant initial concentrations with value as shown in Table 1 and compared the result with Iraqi standard where Table 2 is the specifications Iraqi standard for water and Table 3 is the classification of rivers in terms of pollution. The experimental work procedure is shown in Figure 3.
Figure 3. The experimental work procedure
Table 2. Specifications of the Iraqi standard for water
|
Properties |
Iraqi Environmental Legislation (mg/L) (1967) |
WHO Environmental Legislation (mg/L) (2011) |
|
pH |
6.5-8.5 |
6.9-9.5 |
|
BOD |
5 |
low 5 |
|
COD |
100 |
low 3 |
|
TSS |
30 |
10_20 |
|
TDS |
1500 |
1000 |
|
PO4 |
3 |
0.5 |
|
NO3 |
50 |
50 |
|
Cl |
250_350 |
45_250 |
|
Cu |
0.05 |
2 |
|
Co |
0.05 |
This has not established a specific guideline for the value of cobalt in drinking water. This decision is due to the limited data on the health effects of cobalt at concentrations typically found in drinking water. |
Table 3. Classification of rivers in terms of pollution
|
Classification of a River |
BOD5 (mg/L) |
|
Very clean |
1 |
|
Clean |
2 |
|
Fairly clean |
3 |
|
Questionable cleanliness |
5 |
|
Bad |
More than 10 |
In this study, an insight into the occurrence, persistence, and removal of BOD5, COD, TSS, PO4, pH, TDS, dissolved oxygen (DO), Total organic carbon (TOC), NO3, Cl, Co, and Cu from hospital wastewater by flash graphene. To choose the optimal performance of the selected parameter values, these numbers for the lowest pollutant concentration are based constructively on the literature review of previous adsorption batch mode studies in scientific research [27]. Comparing the choosing parameter in Table 1 with the Iraqi standard in Tables 2 and 3, we note that it exceeds the limiting value.
3.1 Effect of adsorbent dosage
Different quantities of flash graphene sorbent were added to four 250 ml conical flasks for each adsorption test run. Each of the four samples was a water sample at room temperature with consistent time, rpm, and pH values. There were four dosage-weighted levels: 0.5, 1, 1.5, and 2 g. As an adsorbent, 100 milliliters of actual medical wastewater were placed inside each conical flask for 60 minutes at 8.2 pH and 200 rpm. Table 4 displays the remedial outcomes of this project. One crucial adsorption characteristic is the adsorbent's surface area. When the adsorbent has a large surface area, its sites are more reactive to metal-ion interaction [28]. The active locations that the pollutants will occupy are largely determined by surface area. As a result, a material's ability to absorb additional contaminants is increased when its surface area grows [29].
As shown in Figures 4(f) and (h), the best removal was at 2 g of flash graphene for PO4 and Cl. It is evident that as the sorbent dose has increased, so has the removal efficiency. While TDS, COD, TOC, NO3, Co, and Cu were removed at 0.5 g from flash graphene, as clear in Figures 4(a), (d), (e), (g), (j) and (k), respectively, that prove the efficient of small amount of flash graphene for remove the mention pollution. While 1 g of flash graphene is sufficient for the removal of BOD5 and TSS, as shown in Figures 4(c) and (i), respectively, and finally, 1 g of flash graphene is enough to reduce DO, as shown in Figure 4(b). As the sorbent dose in the solution increased, more sorption sites became available, which is why this behavior was anticipated. Additionally, it demonstrated that the amount of flash graphene in the solution stays constant even after the sorbent dose is added, since the total sorption sets the amount of this pollutant to the sorbent after a specific sorbent dose.
Table 4. Effect of adsorbent dosage
|
Dose |
TDS |
DO |
BOD |
COD |
TOC |
PO4 |
NO3 |
Cl |
TSS |
Co |
Cu |
|
0.5 |
1910 |
2.4 |
0.24 |
ND |
ND |
32.87 |
0.9 |
440 |
62 |
ND |
0.205 |
|
1 |
1920 |
2.16 |
0 |
ND |
ND |
18.99 |
0.92 |
440 |
16 |
ND |
0.216 |
|
1.5 |
1970 |
1.92 |
0 |
8 |
1.6 |
11.9 |
0.85 |
440 |
16 |
ND |
0.295 |
|
2 |
1970 |
2.2 |
1 |
ND |
ND |
2.26 |
4.18 |
400 |
106 |
ND |
0.205 |
(a)
(b)
(c)
(d)
(e)
(f)
(g)
(h)
(i)
(j)
(k)
Figure 4. Effect of adsorption dose (a) TDS, (b) DO, (c) BOD, (d) COD, (e) TOC, (f) PO4, (g) NO3, (h) Cl, (i) TSS, (j) Co, (k) Cu
3.2 Effect of contact time
The equilibrium time should be determined to achieve equilibrium concentrations [30]. Medical real wastewater solutions taste the effect of contact time by choosing five different times (15, 30, 60, 90, 120 min) (Table 5). Under 2 g from the adsorbent flash, graphene was added to 100 ml of the solution at room temperature with 8.7 pH and a shaking speed of 200 rpm. The result value is described in Figure 5. At contact time of 15 min, Cl and TSS were removed as shown in Figures 5(h) and (i), and at 30 min, Do, BOD, COD, and TOC was removed as shown in Figures 5(b), (c), (d), and (e). Also, at 60 min, PO4 and Cu were removed, as shown in Figures 5(f) and (k). This figure demonstrates how the percentage of these pollutants removed rose noticeably as contact time increased. The sorption rate was high in the beginning and gradually decreased. A decrease in sorption sites on the surface of the flash graphene was most likely the cause of the slower sorption [31].
Table 5. Effect of contact time
|
Time min. |
TDS |
DO |
BOD |
COD |
TOC % |
PO4 |
NO3 |
Cl |
TSS |
Co |
Cu |
|
15 |
1910 |
1.36 |
0.32 |
8 |
1.6 |
3.21 |
2.89 |
380 |
97 |
ND |
0.273 |
|
30 |
1950 |
1.08 |
0.08 |
ND |
ND |
2.68 |
4.34 |
400 |
97 |
ND |
0.284 |
|
60 |
1970 |
2.2 |
1 |
ND |
ND |
2.26 |
4.18 |
400 |
106 |
ND |
0.205 |
|
90 |
1850 |
2.08 |
1.28 |
ND |
ND |
10.63 |
3.09 |
380 |
103 |
ND |
0.398 |
|
120 |
1630 |
1.32 |
0.16 |
ND |
ND |
17.3 |
2.89 |
380 |
107 |
ND |
0.25 |
(a)
(b)
(c)
(d)
(e)
(f)
(g)
(h)
(i)
(j)
(k)
Figure 5. Effect of contact time (a) TDS, (b) DO, (c) BOD, (d) COD, (e) TOC%, (f) PO4, (g) NO3, (h) Cl, (i)TSS, (j) Co, (k) Cu
3.3 Effect of pH
The solution's pH impacted the adsorbent surface's electrical charge and the adsorbate molecule's ionic forms [32]. The solution's initial pH is the most important single parameter influencing the sorption capacity. The effect of pH value was tested with three different values of 5, 7.3, and 8.5 and a fixed condition of 60 min shaking time with 2 g of flash graphene and 200 rpm shaking speed. Table 6 shows the removal result after adsorption by flash graphene. From Figures 6(a) to (e) and (h, I, and k), higher removal efficiency was observed at a pH value of 5, while PO4 was removed at a pH value of 7.3, as shown in Figure 6(f). Also, NO3's best pH value at 8.5 is clear in Figure 6(j).
Table 6. pH value
|
pH |
TDS |
DO |
BOD |
COD |
TOC % |
PO4 |
NO3 |
Cl |
TSS |
Co |
Cu |
|
5 |
2140 |
3.2 |
0.24 |
8 |
1.6 |
5.54 |
0.88 |
440 |
150 |
0 |
0.352 |
|
7.3 |
2070 |
2.88 |
0.08 |
0 |
0 |
23.13 |
0.55 |
400 |
16 |
0 |
0.216 |
|
8.5 |
2040 |
2.32 |
0 |
8 |
1.6 |
10.41 |
0.95 |
420 |
33 |
0 |
0.25 |
(a)
(b)
(c)
(d)
(e)
(f)
(g)
(h)
(i)
(j)
(k)
Figure 6. Effect of pH value (a) TDS, (b) DO, (c) BOD, (d)COD, (e) TOC%, (f) PO4, (g) NO3, (h) Cl, (i)TSS, (j) Co, (k) Cu
3.4 Shaking speed
Four different shaking speeds were examined by adding 2 g of flash graphene to 100 mL of real medical wastewater in a 250 mL conical flask with 7.3 pH and a shaking time of 60 minutes, as shown in Table 7, which shows the removal percentage. At a shaking speed of 150 rpm, TDS, DO, and Cl were removed, as shown in Figures 7(a), (b), and (h), while BOD and TSS were removed at 250 rpm shaking speeds, respectively, as is clear in Figures 7(c) and (i). Furthermore, NO3, Cu, and COD are removed at a shaking speed of 100, as shown in Figures 7(f), (d), and (k), which shows a notable reduction in values.
Table 7. Effects of shaking speed
|
Time min. |
TDS |
DO |
BOD |
COD |
TOC % |
PO4 |
NO3 |
Cl |
TSS |
Co |
Cu |
|
100 |
1970 |
2.72 |
0.32 |
ND |
ND |
19.1 |
0.51 |
480 |
100 |
ND |
0.136 |
|
150 |
1960 |
1.96 |
1 |
40 |
8 |
30.54 |
1.22 |
360 |
108 |
ND |
0.205 |
|
200 |
1970 |
2.2 |
1 |
ND |
ND |
2.26 |
4.18 |
400 |
106 |
ND |
0.205 |
|
250 |
2100 |
2.24 |
0 |
16 |
3.2 |
15.5 |
0.66 |
440 |
50 |
ND |
0.159 |
(a)
(b)
(c)
(d)
(e)
(f)
(g)
(h)
(i)
(j)
(k)
Figure 7. Effect of shaking speed (a) TDS, (b) DO, (c) BOD, (d) COD, (e) TOC%, (f) PO4, (g) NO3, (h) Cl, (i)TSS, (j) Co, (k) Cu
3.5 Discussion
The results obtained in this study demonstrate the high efficiency of FG, synthesized from orange peel using FJH, in removing a wide range of pollutants from hospital wastewater. The findings were compared with results reported in prior research to evaluate the performance of FG in relation to other adsorbents and treatment technologies.
Table 8 showed excellent removal efficiency of Flash graphene for BOD₅, achieving 100% removal within 90 minutes using only 1 gram of adsorbent. In comparison, conventional treatment systems reported in previous studies achieved only around 60% BOD₅ removal efficiency [3]. Similarly, COD was completely removed within just 15 minutes in this study, outperforming membrane bioreactor (MBR) systems that achieved approximately 75% COD reduction [9].
Table 8. Summary
|
Pollutant |
This Study (FG from Orange Peel) |
Previous Research & Method |
Reported Removal Efficiency |
Reference |
|
BOD₅ |
100% in 90 min (1 g FG) |
Conventional treatment |
~60% |
[3] |
|
COD |
100% in 15 min (0.5 g FG) |
MBR |
~75% |
[9] |
|
TOC |
Full removal at 15 min |
Graphene oxide-based |
80–85% |
[20] |
|
Cu²⁺ |
57.4% at 90 min |
Graphene/Chitosan composite |
~70% |
[32] |
|
Co²⁺ |
Fully removed (15–60 min) |
Not reported (rarely studied) |
N/A |
- |
This study recorded notable removal efficiencies for several inorganic pollutants. Total dissolved solids (TDS) were reduced to acceptable levels at minimal contact time, and phosphate (PO₄³⁻) removal was highly effective at pH 7.3. For nitrate (NO₃⁻), optimal removal occurred at pH 8.5. These results align with, and in some cases exceed, previous studies that used FG synthesized from banana peels and plastic waste [21, 27].
In terms of heavy metals, copper (Cu²⁺) and cobalt (Co²⁺) were effectively removed, with up to 57.4% and full removal, respectively, under optimized batch conditions. Comparable results were reported using a graphene oxide/chitosan nanocomposite, although that system required higher adsorbent doses and longer contact times [32].
|
ml |
Milliliters |
|
g |
Gram |
|
rpmr |
Rotation per minute |
|
t |
Time |
|
T |
Temperature, ℃ |
|
Subscripts |
|
|
AC |
Activated carbon |
|
OP |
Orange peel |
|
FG |
Flash graphene |
|
FJH |
Flash Joule heating |
[1] Kwikiriza, S., Stewart, A.G., Mutahunga, B., Dobson, A. E., Wilkinson, E. (2019). A whole systems approach to hospital waste management in rural Uganda. Frontiers in Public Health, 7: 136. https://doi.org/10.3389/fpubh.2019.00136
[2] Liu, A., Zhao, Y., Cai, Y., Kang, P., Huang, Y., Li, M., Yang, A. (2023). Towards effective, sustainable solution for hospital wastewater treatment to cope with the post-pandemic era. International Journal of Environmental Research and Public Health, 20(4): 2854. https://doi.org/10.3390/ijerph20042854
[3] Amouei, A., Asgharnia, H., Fallah, H., Faraji, H., Barari, R., Naghipour, D. (2015). Characteristics of effluent wastewater in hospitals of Babol University of Medical Sciences, Babol, Iran. Health Scope, 4(2): e23222.
[4] Salih, A.L.M., Al-Qaraghul, S.A., Idan, R.M. (2018). Geochemical study of the Tigris River sediments in the surrounding area of Baghdad Medical City. International Journal of GEOMATE, 15(52): 192-198. https://doi.org/10.21660/2018.52.4674
[5] Hassan, N.E. (2023). An investigation of heavy metal concentration in rainwater and its effects on human health in the Kurdistan Region, Iraq. GSC Advanced Research and Reviews, 17(2): 229-239. https://doi.org/10.30574/gscarr.2023.17.2.0451
[6] Crossingham, J. (2009). Medical waste. British Journal of General Practice, 59(563): 451. https://doi.org/10.3399/bjgp09X421021
[7] Kumari, A., Maurya, N.S., Tiwari, B. (2020). Hospital wastewater treatment scenario around the globe. In Current Developments in Biotechnology and Bioengineering, pp. 549-570. https://doi.org/10.1016/b978-0-12-819722-6.00015-8
[8] Boillot, C., Bazin, C., Tissot-Guerraz, F., Droguet, J., Perraud, M., Cetre, J.C., Trepo, D., Perrodin, Y. (2008). Daily physicochemical, microbiological, and ecotoxicological fluctuations of a hospital effluent according to technical and care activities. Science of the Total Environment, 403: 113-129. https://doi.org/10.1016/j.scitotenv.2008.04.037
[9] Patel, M., Kumar, R., Kishor, K., Mlsna, T., Pittman, C.U., Mohan, D. (2019). Pharmaceuticals of emerging concern in aquatic systems: Chemistry, occurrence, effects, and removal methods. Chemical Reviews, 119(6): 3510-3673. https://doi.org/10.1021/acs.chemrev.8b00299
[10] Ansari, M., Ehrampoush, M.H., Farzadkia, M., Ahmadi, E. (2019). Dynamic assessment of economic and environmental performance index and generation, composition, ecological and human health risks of hospital solid waste in developing countries; A state of the art of review. Environment International, 132: 105073. https://doi.org/10.1016/j.envint.2019.105073
[11] Saguti, F., Magnil, E., Enache, L., Churqui, M.P., et al. (2021). Surveillance of wastewater revealed peaks of SARS-CoV-2 preceding those of hospitalized patients with COVID-19. Water Research, 189: 116620. https://doi.org/10.1016/j.watres.2020.116620
[12] Cai, L., Zhang, T. (2013). Detecting human bacterial pathogens in wastewater treatment plants by a high-throughput shotgun sequencing technique. Environmental Science & Technology, 47(10): 5433-5441. https://doi.org/10.1021/es400275r
[13] Azuma, T., Hayashi, T. (2021). On-site chlorination was responsible for the effective disinfection of wastewater from the hospital. Science of the Total Environment, 776: 145951. https://doi.org/10.1016/j.scitotenv.2021.145951
[14] Aydin, S., Aydin, M.E., Ulvi, A., Kilic, H. (2018). Antibiotics in hospital effluents: Occurrence, contribution to urban wastewater, removal in a wastewater treatment plant, and environmental risk assessment. Environmental Science and Pollution Research, 26: 544-558. https://doi.org/10.1007/s11356-018-3563-0
[15] Rodriguez-Mozaz, S., Lucas, D., Barceló, D. (2018). Full-scale plants for dedicated treatment of hospital effluents. In Hospital Wastewaters: Characteristics, Management, Treatment and Environmental Risks, pp. 189-208. https://doi.org/10.1007/698_2017_13
[16] Verlicchi, P., Al Aukidy, M., Zambello, E. (2015). What have we learned from worldwide experiences on the management and treatment of hospital effluent? An overview and a discussion on perspectives. Science of the Total Environment, 514: 467-491. https://doi.org/10.1016/j.scitotenv.2015.02.020
[17] Tchobanoglus, G., Burton, F., Stensel, H.D. (2003). Wastewater engineering: treatment and reuse. American Water Works Association. Journal, 95(5): 201.
[18] Hu, Z., Grasso, D. (2005). Water Analysis | Chemical oxygen demand. Encyclopedia of Analytical Science, 325-330. https://doi.org/10.1016/B0-12-369397-7/00663-4
[19] Kümmerer, K. (2001). Drugs in the environment: emission of drugs, diagnostic aids, and disinfectants into wastewater by hospitals about other sources − A review, Chemosphere, 45(6-7): 957-969. https://doi.org/10.1016/S0045-6535(01)00144-8
[20] Salih, W.K., Mohammed, S.A.M., Abdulmajeed, B.A. (2023). Graphene oxide: A key solution for future: Recent achievements as a new adsorbent for water treatment applications: Review. Iraqi Journal of Science, 64(10): 4958-4970. https://doi.org/10.24996/ijs.2023.64.10.6
[21] Luong, D.X., Bets, K.V., Algozeeb, W.A., Stanford, M.G., et al. (2020). Gram-scale bottom-up flash graphene synthesis. Nature, 577: 647-651. https://doi.org/10.1038/s41586-020-1938-0
[22] Algozeeb, W.A., Savas, P.E., Luong, D.X., Chen, W., Kittrell, C., Bhat, M., Shahsavari, R., Tour, J.M. (2020). Flash graphene from plastic waste. ACS Nano, 14(11): 15595-15604. https://doi.org/10.1021/acsnano.0c06328
[23] Alkhawaja, E.S., Abdul-Hameed, H.M. (2025). Novel synthesis and characterization of nano-activated carbon derived from agricultural orange peel waste. International Journal of Design & Nature and Ecodynamics, 20(1): 31-41. https://doi.org/10.18280/ijdne.200104
[24] Graimed, B.H., Ali, Z.T.A. (2022). Green approach for synthesizing graphene glass hybrid as a reactive barrier for remediation of groundwater contaminated with lead and tetracycline. Environmental Nanotechnology, Monitoring & Management, 18: 100685. https://doi.org/10.1016/j.enmm.2022.100685
[25] Ahmed, D.N., Hussein, M.A., Abdul-Kareem, M.B., Hassan, W.H., Al-Ansari, N., Faisal, A.A. (2023). Green synthesis of hybrid iron oxides/graphene immobilization on the iron slag for reclamation Congo red dye-water. Water, Air, & Soil Pollution, 234(12): 778. https://doi.org/10.1007/s11270-023-06806-7
[26] Fadhil, H.A., Samir, A.H. (2024). Synthesis, characterization of novel modified reduced graphene oxide (RGO) containing heterocyclic compounds. Ibn AL-Haitham Journal for Pure and Applied Sciences, 37(3): 239-253.
[27] Raheem, N.S., Abdul-Hameed, H.M. (2024). Groundwater remediation using flash graphene produced from banana peels: Batch mode. International Journal of Environmental Impacts, 7(2): 319-327. https://doi.org/10.18280/ijei.070216
[28] AL-Hussain, Z.K.A., Abdul-Hameed, H.M. (2023). Remove lead ions from wastewater by using a local adsorbent from charring tea wastes. Iraqi Journal of Chemical and Petroleum Engineering, 24(3): 93-102. https://doi.org/10.31699/IJCPE.2023.3.9
[29] Mhawesh, T.H., Abd Ali, Z.T. (2020). Reuse of brick waste as a cheap sorbent for the removal of nickel ions from aqueous solutions. Iraqi Journal of Chemical and Petroleum Engineering, 21(2): 15-23. https://doi.org/10.31699/IJCPE.2020.2.3
[30] Ibrahim, S.M., Ali, Z.T.A. (2020). Removal of acidic dye from aqueous solution using surfactant modified bentonite (organoclay): Batch and kinetic study. Journal of Engineering, 26(5): 64-81. https://doi.org/10.31026/j.eng.2020.05.05
[31] Al-Khatib, L., Fraige, F., Al-Hwaiti, M., Al-Khashman, O. (2012). Adsorption from aqueous solution onto natural and acid activated bentonite. American Journal of Environmental Sciences, 8(5): 510-522. https://doi.org/10.3844/ajessp.2012.510.522
[32] Kadhim, H.H., Saleh, K.A. (2022). Removal of copper ions from industrial wastewater using graphene oxide/chitosan nanocomposite. Iraqi Journal of Science, 63(5): 1894-1908. https://doi.org/10.24996/ijs.2022.63.5.4
