Wastewater Treatment Purposes Research Articles

Surface Functionalization of Biochar from Oil Palm Empty Fruit Bunch through Hydrothermal Process

The use of biochar as an adsorbent for wastewater treatment purposes has been hindered due to its lower surface area compared to activated carbon. Current research on increasing surface functional groups on biochar surfaces to improve its adsorption performance suggests using high chemical concentration and long period of modification. This study solves these problems by focusing on improving surface functionalities of biochar via the hydrothermal functionalization process. Oil palm empty fruit bunch biochar was functionalized using autoclave with nitric acid as the functionalization agent. Functionalized biochar properties such as Brunauer–Emmett–Teller (BET) surface area and surface functional groups were analyzed and compared with untreated biochar. Fourier Transform Infrared (FTIR) spectroscopic analysis shows a significant increase in absorption by oxygen functional groups and is corroborated with energy dispersive X-ray (EDX) analysis. The process does not result in any major change in surface morphology and reduction in surface area value. Methylene blue (MB) adsorption test shows 7 times increase in adsorption performance. These results show that the simple hydrothermal functionalization process successfully functionalizes the biochar surface and improves its performance without affecting its surface area at lower concentration, and shorter time compared to previous studies. This result, with future large-scale experimentation using real-life equipment in palm oil mills, would provide a better technology that can be implemented in the industry.

Influence of dielectric coatings on pin-to-rod nanosecond-pulsed discharges in phosphate-buffered saline.

Plasma medicine is a rapidly expanding field that utilizes non-equilibrium plasma discharges at atmospheric conditions or in liquids for clinical applications. There is significant interest in the production of plasma in the liquid phase for wastewater treatment, agricultural applications, and medical purposes. However, little investigation has been done about the effects of dielectric coatings on submerged electrodes, which is of significant interest to limit electrical current flow in the liquid. This work investigates the effect of different dielectric coatings including aluminum oxide, parylene C, and bi-layer combinations, on plasma discharge characteristics in phosphate-buffered saline (σ = 18 mS/cm) from nanosecond high-voltage pulses. Observed results for aluminum oxide are consistent with past works, including micron-sized clusters of holes generated in the layer due to dielectric breakdown. A bi-layer combination of parylene C on top of aluminum oxide resulted in longer lifetime for electrodes, possibly due to the melting/solidification behavior of the polymer, which may have a "healing" effect. The use of a thick parylene C layer resulted in a different, "creeping", discharge regime, which is hypothesized to be similar to triple-gap discharge observed in space plasma physics and high-voltage insulators, in which the electric field is enhanced at the boundary of a conductor, dielectric, and a vacuum/fluid, resulting in discharge at this junction point. Temporally-resolved and high-spatial-resolution imaging are required for verification.

Synergistic effects of water temperature, microplastics and ammonium as second and third order stressors on Daphnia magna

Daphnids, including the water flea Daphnia magna, can be exploited for wastewater treatment purposes, given that they are filter feeder organisms that are able to remove suspended particles from water. The presence of pollutants, such as microplastics and chemicals, might be considered stressors and modify the behaviour and survival of D. magna individuals. The impact of the cumulative pollutants that regulate the fate of living organisms has yet to be fully determined. Here we present the effect of double and triple combinations of stressors on the behaviour of D. magna. The impact of water temperature, ammonium and polystyrene microplastics on the filtration capacity and survival of D. magna is studied. Water temperatures of 15 °C, 20 °C and 25 °C, microplastic-to-food ratios of 25% and 75%, and ammonium concentrations of 10 and 30 mg N–NH4+ L−1 are tested after making dual and triple combinations of the parameters. A synergistic effect between water temperature and ammonium is normally observed but not in the case of the lower values of ammonium concentration and temperature. The combination of three stressors (water temperature, microplastics and ammonium) is also found to be synergistic, producing the greatest impact on D. magna filtration capacity and reducing their survival. In comparison with the effect of the two stressor conditions, the combination of the three stressors caused a reduction of between 13.1% and 91.7% in the t50% time (the time required for a 50% reduction in the D. magna filtration capacity) and a reduction of between 4.8% and 54.5% in TD50 (the time for 50% mortality).

Synthesis and characterization of ZnO-TiO2/CoFe2O4 hollow photocatalyst: Magnetic recovery and highly efficient photocatalytic performance

TiO2 has been known as an excellent semiconductor photocatalyst for wastewater treatment purposes. But, its visible light efficiency is low and cannot be easily recovered from the reaction mixture. In order to overcome these major disadvantages, a novel hollow magnetically recoverable ZnO-TiO2/CoFe2O4 photocatalyst is synthesized by the sol–gel and layer self-assembly methods. The synthesized photocatalyst was characterized by means of X-ray diffractometer (XRD), Transmission electron microscopy (TEM), Vibrating sample magnetometer (VSM), Fluorescence spectrometer (FL), and UV-Vis/DRS techniques. Complete degradation of rhodamine B is attained in the presence of ZnO-TiO2/CoFe2O4 photocatalyst under the irradiation of ultraviolet and sunlight within 90[Formula: see text]min. The photocatalyst can be repeatedly reused for five times without significantly diminishing of its photocatalytic performance.

Sono-electro-chemical Treatment of Reactive Black 5 Dye and Real Textile Effluent Using MnSO4/Na2S2O8 Electrolytes

This study examines the decolourization of Reactive Black 5 (RB5) dye in aqueous solution and textile wastewater treatment by sono-electro-chemical method to obtain synergistic effect. The electrolytic cell equipped with stainless steel anode and graphite cathode was used for this study. Sodium persulphate (NaS) and manganese sulphate (MnS) are used as electrolytes to facilitate the process. The effects of various operational parameters such as initial solution pH, NaS concentration, MnS concentration, ultrasound power and voltage on the sono-electro-chemical treatment were investigated. The results have demonstrated that the enhanced colour removal efficiency was achieved at pH 2 for electro-chemical process; however, better efficiency was reached by synergistic effect of sono-electro-chemical treatment in the presence of less amount of electrolytes with the short reaction time than the individual sono-chemical and electro-chemical process. The maximum decolourization achieved was 89% under the condition: 100 ppm RB5, 50 ppm NaS, 75 ppm MnS, solution pH and 44 W ultrasound power, 20 V. When the similar methodology was adopted to real textile effluent, 90% of TOC removal was observed and it indicates the employment of studied process for industrial wastewater treatment purposes.

A critical review of waste resources, synthesis, and applications for Zeolite LTA

This review not only provided a summary of the state of the art with regards to commercially important zeolite LTA technology, but also identified strategies to further promote uptake of this material in industry. The hypothesis was that application of SWOT analysis principles would assimilate data regarding zeolite LTA in a manner which provided a concise and clear pathway for future development. Zeolite LTA synthesis innovation related to preparation of nano-zeolites, hierarchical materials, binderless zeolite granules, magnetized zeolites, loading of metals/metal oxides into the pore structure and introduction of heteroatoms. Waste resources included used glass, alum sludge from drinking water plants, fly ash from power stations, recycled aluminium, manufacturing waste, ash from organic material and various aluminosilicate rocks from the mining sector. In addition to traditional application of zeolite LTA for water softening opportunities; use of zeolite LTA for catalytic processes, membrane separation, alternate zeolite production, wastewater treatment, and anti-microbial purposes have been described. A key weakness identified was the lack of compelling economic models in relation to synthesis of zeolite LTA from waste resources or by new methods which produce hierarchical materials. Linked to the lack of economic studies was the limited information about process design of zeolite LTA manufacturing systems or industrial application of zeolite LTA. Key strategies developed included: (1) scaling-up of new synthesis methods to kg levels and beyond; (2) creation of process flow diagrams and piping and instrumentation diagrams; (3) detailed economic analysis of zeolite LTA synthesis from waste materials; (4) Utilization of methods to reduce the cost of zeolite manufacture such as ultrasonics, microwaves, “one pot” synthesis, continuous production and rapid synthesis; and (5) demonstration of zeolite LTA performance at pilot plant scale for the various applications identified. In conclusion, zeolite LTA has an expanded role to play in the area of zeolite science and this study has provided a roadmap to accelerate this development.

Exfoliated kaolinite nanolayers as an alternative photocatalyst with superb activity

In searching for alternative and abundant photocatalyst, exfoliated kaolinite nanolayers (nK) were prepared by a simple intercalation process. The effect of intercalating agents on the produced nK was studied by different instrumentations. XRD, FT-IR, and TEM confirm the exfoliation of kaolinite into nanolayers. Bandgap values were altered depending on intercalating agents as revealed by light absorption spectra. Photogenerated charge carriers observed through photoluminescence spectra. The produced nK applied for photodegradation of Rhodamine B dye (RhB) as an industrial model for wastewater treatment purposes. The results showed a complete photodegradation of RhB within a few minutes under UV with superb reaction kinetics. We refer the enhanced photocatalytic properties to the exposed metal oxide impurities on the surface of nK due to exfoliation. Performance tests revealed the reusability and stability of the prepared nK. This plentiful material is supposed to be a versatile alternative for the well-known photocatalysts with the possibility of large-scale production. Photodegradation mechanism of RhB is proposed.

Biofiltration using C. fluminea for E.coli removal from water: Comparison with ozonation and photocatalytic oxidation

Corbicula fluminea, an Asian clam, is one of the worst invasive species in Europe that can survive in very adverse environmental conditions. Despite its negative impacts, the species also has the capacity to bioaccumulate heavy metals, contaminants and can be exploited for wastewater treatment purposes. The capacity of the Asian clam to remove Escherichia coli, used as fecal contamination indicator, was analyzed. Conventional wastewater treatment plants are not suitable to remove bacteria, thus resulting in treated municipal wastewater with high bacterial loads. E. coli clearance rate was analyzed as function of the number of clams. The bivalves can remove bacteria until concentrations below the detection limit in about 6 h. The adsorption on the clam shells’ and bioaccumulation on the soft tissues were also analyzed. The depuration of clams along 48 h were analyzed revealing that no bacteria was detected in the water. Thus, these results suggest that Asian clam can bioprocess E. coli. On the other hand, results obtained by this methodology were compared with ozonation and photocatalytic oxidation using TiO2, Ag, Au, Pd-TiO2. In all treatments it was possible to achieve concentrations of E. coli below the detection limit. However, photocatalytic oxidation demands about 4700 folds more energy than ozonation, besides the costs associated with catalysts. Comparing complexity of ozonation with biofiltration, this study suggests that application of biofiltration using C. fluminea can be a suitable solution to minimize the presence of bacteria in wastewater, reducing environmental and economic impacts.

Comparative Performance of Tetraphosphonate and Diphosphonate as Reverse Osmosis Scale Inhibitors

Reverse osmosis (RO) technologies are widely used throughout the world for drinking, industrial and waste water treatment purposes. Proper and economically attractive operation of RO installations should be provided by the correct maintenance of all technical process parameters. One of the significant operational problems is precipitation and deposition of sparingly-soluble salts on the membrane surface, which can be prevented by dosing special chemical additives into the feed solution. The aim of the present work is to reveal the structure/function relationship of phosphonate scale inhibitors, which possess systematic structural similarities and differences. Specifically, two classes of tetraphosphonate (5 additives) and diphosphonate (6 additives) have been tested as calcium carbonate scale inhibitors on the lab membrane unit. It was found that among the family of tetraphosphonates and diphosphonates the inhibitor efficiency increases with elongation –(CH2)– chain, but the longest additives have a sharp drop in inhibition efficiency.

Use of halophytes in pilot-scale horizontal flow constructed wetland treating domestic wastewater.

Recent findings encourage the use of halophytes in constructed wetlands for domestic wastewater treatment due to their special physiological characteristics as the ability to accumulate heavy metals and salts in their tissues makes them ideal candidates for constructed wetland vegetation. In this particular study, we investigated the application of halophytic plants in a horizontal flow constructed wetland for domestic wastewater treatment purposes. The pilot plant which was situated in Crete (Greece) was planted with a polyculture of halophytes (Tamarix parviflora, Juncus acutus, Sarcocornia perrenis, and Limoniastrum monopetalum). The system's performance was monitored for a period of 11months during which it received primary treated wastewater from the local wastewater treatment plant. Results show that halophytes developed successfully in the constructed wetland and achieved organic matter and pathogen removal efficiencies comparable to those reported for reeds in previous works (63% and 1.6 log units, respectively). In addition, boron concentration in the effluent was reduced by 40% in comparison with the influent. Salinity as expressed by electrical conductivity did not change during the treatment, indicating that the accumulation of salts in the leaves is not able to overcome electrical conductivity increasing due to evapotranspiration. The results indicate an improvement in the treatment of domestic wastewater via the use of halophyte-planted CWs.

Methane dependent denitrification- from ecosystem to laboratory-scale enrichment for engineering applications

Managing nitrogen and carbon cycles in engineered and natural ecosystems is an environmental challenge. In this manuscript, we report a process which connects these two cycles with immense ecological and engineering significance. Sediments, collected from Jordan River in Salt Lake City, Utah were used as seed to start a laboratory-scale denitrification coupled to anaerobic methane oxidation (n-DAMO) reactor fed with methane (CH4) and nitrite (NO2−). Methane (CH4)-dependent denitrification in sediments of a nutrient-impaired river was found to be in the range of 40 nmol kg−1 d−1 to 70 nmol kg−1 d−1. Post 19 months of operation of the lab scale reactor, the n-DAMO reactor achieved nitrite removal rate of 2.88 mmol L−1 d−1. Enrichment of n-DAMO prokaryotes was evident from the increase in 16S rRNA gene copy number of bacteria belonging to the NC10 phylum in the reactor, corroborating with increase in the oxidation rates of CH4 coupled with NO2−-N removal from 21 μM to 190 μM of CH4 d−1. Based on stable isotope experiments by other researchers, nitric oxide dismutase (nod) functional gene was hypothesized to be responsible for splitting nitric oxide to nitrogen and oxygen and this internally generated oxygen is utilized by n-DAMO prokaryotes to oxidize methane gas. Primers targeting the unique nitric oxide dismutase (nod) gene were developed and tested on the enrichment culture for the first time. This revealed that n-DAMO organisms are closely related yet distinct from, the M. oxyfera which had been enriched in earlier studies. The results emphasize tremendous future promise to use these novel organisms for wastewater treatment purposes, especially to take advantage of the dissolved methane present in anaerobic digester effluents.

Macroinvertebrate assemblages and biodiversity levels: ecological role of constructed wetlands and artificial ponds in a natural park

Constructed wetlands play an important role in water supply, floodwater retention and nutrient removal, at the same time allowing the restoration of lost habitat and the preservation of biodiversity. There is little knowledge about the biodiversity that can be found in these artificial environments along time, especially at the invertebrate community level. Macroinvertebrate assemblages, water chemistry, morphology, and environmental characteristics of natural ponds, artificial pools and constructed wetlands in Parco Pineta (Northern Italy) were studied to evaluate the effects of local factors on macroinvertebrate communities. The objective was to verify if each ecosystem could equally contribute to local biodiversity, regardless of its natural or artificial origin. Principal Components Analysis showed that ponds were divided into clusters, based on their morphology and their water quality, independently from their origin. The composition of macroinvertebrate communities was similar among natural wetlands and ponds artificially created to provide new habitats in the park, while it was different among natural wetlands and constructed wetlands created for wastewater treatment purposes. Biodiversity of natural ponds and constructed wetlands, evaluated using taxa richness, Shannon index, and Pielou index, was comparable. Canonical Correspondence Analysis highlighted differences in macroinvertebrate community composition and pointed out the relationships among macroinvertebrates and various environmental variables: habitat heterogeneity resulted as the most relevant factor that influences taxa richness. Water quality also affects the macroinvertebrate community structure. We determined that constructed wetlands with higher pollutant concentrations show different assemblage compositions but comparable overall macroinvertebrate biodiversity. Constructed wetlands became valuable ecological elements in the area almost immediately, due to fast colonizing invertebrates. However, we also assume that differences in macroinvertebrate assemblage compositions among wetlands with different origins lead to differences in the functionality of each ecosystem.

Effects of High Nutrient Supply on the Growth of Seven Bamboo Species

Over the last decade, bamboo has emerged as an interesting plant for the treatment of various polluted waters using plant-based wastewater treatment systems. In these systems, nitrogen and phosphorous concentrations in wastewater can exceed plant requirements and potentially limit plant growth. The effects of two nutrient rates on the growth of seven bamboo species were assessed in a one-year experiment: Dendrocalamus strictus, Thyrsostachys siamensis, Bambusa tuldoides, Gigantochloa wrayi, Bambusa oldhamii, Bambusa multiplex and Bambusa vulgaris. Nutrient rates were applied with a 20:20:20 NPK fertilizer as 2.6 and 13.2 t.ha.yr−1NPK to three-year-old bamboo planted in 70 L containers. Morphological characters, photosynthetic responses, and NPK content in bamboo tissues were investigated. Under high-nutrient supply rate, the main trend observed was an increase of culm production but the culms’ diameters were reduced. For the seven species, the aboveground biomass yield tended to increase with high-nutrient rate. Increasing in nutrient rates also improved the photosynthetic activity which is consistent with the increase of nitrogen and phosphorus contents measured in plant tissues. All the bamboo species tested appears suitable for wastewater treatment purposes, but the species Bambusa oldhamii and Gigantochloa wrayi showed the higher biomass yield and nutrient removal.

Efficient removal of antibiotics in surface-flow constructed wetlands, with no observed impact on antibiotic resistance genes

Recently, there have been growing concerns about pharmaceuticals including antibiotics as environmental contaminants. Antibiotics of concentrations commonly encountered in wastewater have been suggested to affect bacterial population dynamics and to promote dissemination of antibiotic resistance. Conventional wastewater treatment processes do not always adequately remove pharmaceuticals causing environmental dissemination of low levels of these compounds. Using constructed wetlands as an additional treatment step after sewage treatment plants have been proposed as a cheap alternative to increase reduction of wastewater contaminants, however this means that the natural microbial community of the wetlands becomes exposed to elevated levels of antibiotics. In this study, experimental surface-flow wetlands in Sweden were continuously exposed to antibiotics of concentrations commonly encountered in wastewater. The aim was to assess the antibiotic removal efficiency of constructed wetlands and to evaluate the impact of low levels of antibiotics on bacterial diversity, resistance development and expression in the wetland bacterial community. Antibiotic concentrations were measured using liquid chromatography–mass spectrometry and the effect on the bacterial diversity was assessed with 16S rRNA-based denaturing gradient gel electrophoresis. Real-time PCR was used to detect and quantify antibiotic resistance genes and integrons in the wetlands, during and after the exposure period. The results indicated that the antibiotic removal efficiency of constructed wetlands was comparable to conventional wastewater treatment schemes. Furthermore, short-term treatment of the constructed wetlands with environmentally relevant concentrations (i.e. 100–2000ng×l−1) of antibiotics did not significantly affect resistance gene concentrations, suggesting that surface-flow constructed wetlands are well-suited for wastewater treatment purposes.

Removal of ammonium ion from aqueous solutions using natural zeolite: kinetic, equilibrium and thermodynamic studies

The aim of the present study is to investigate the removal of ammonium ions from aqueous solutions using the natural Western Azerbaijan zeolite by utilizing ion exchange process. Batch experimental studies were conducted to evaluate by changing relevant parameters such as pH, dosage of adsorbent, stirring time, initial ammonium concentration, and temperature. The results clearly confirmed that all mentioned parameters have vital affects on removing ammonium ions from wastewater and effluents, so got optimized. Adsorption kinetics and equilibrium data for the removal of ammonium ion were analyzed using Langmuir and Freundlich equations. The Langmuir model fits the equilibrium data better than the Freundlich model. According to the Langmuir equation, the maximum uptake for ammonium ion was 43.47 (mg g−1). Pseudo-first-order and pseudo-second-order models were used to represent the kinetics of the process. Kinetic studies showed that the adsorption followed a pseudo-second-order reaction. The calculated thermodynamic parameters (ΔG°, ΔH°, and ΔS°) indicate that the adsorption process is feasible, spontaneous, and endothermic at 20–50 °C. Based on the experimental results, it can be suggested that the natural Western Azerbaijan zeolite has the potential of application as an efficient adsorbent for the removal of ammonium ions from aqueous solutions, and is suggested for wastewater treatment purposes.

ASSESSMENT OF POLYACRYLAMIDE DEGRADATION USING ADVANCED OXIDATION PROCESSES AND FERRATE(VI) OXIDATION

The aim of this work was to investigate the degradation of six polyacrylamide (PAM) polymers when submitted to advanced oxidation processes (AOP) and ferrate(VI) oxidation. PAM is a highly versatile polymer made of acrylamide monomers, and it is widely used for water and wastewater treatment purposes. The degradation of these polymers using Fenton reagent, H2O2/UV, Fe2+/H2O2/UV, and Fe3+/H2O2/UV, as well as ferrate(VI), showed that PAM may present different behaviors under oxidation processes, especially regarding their ionic charge. Among the oxidative processes, the photochemical processes present the best overall results towards PAM degradation. COD and TOC were successfully used to assess PAM degradation, while ammonia determination has shown that •OH radicals produced by AOP tends to rapidly attack the amide group, releasing NH3 as a reaction product. Finally, the influence of each oxidation process, its reagent concentration, and photo-induced conditions on PAM degradation are discussed.

DEWATS Capacity Building for Primary Schools in Jordan and Palestine

Capacity building for Decentralised Wastewater Treatment Solutions (DEWATS) can play a significant role in the alleviation of water constraints in Jordan and Palestine. The paper summarises practical experience with a pilot teaching unit for primary schools based on demonstration technology and capacity building in the field of DEWATS. The training programme has the goal of raising public awareness and understanding of water issues, and gives pupils the opportunity to conduct experiments in water/wastewater analysis and build wastewater filters and construct wetlands models. This training encourages reflection about wastewater components and shows the participants the advantages of wastewater treatment and the potential for reusing wastewater in decentralised systems. Additionally, the experiments help students understand wastewater as a resource, especially in MENA (Middle East and North Africa) regions with water shortages. The students build a constructed wetland model, which helps them to view constructed wetlands treatment systems as a modern and ecological treatment technology that blends in well with the environment and can provide solutions for wastewater treatment and irrigation purposes. The paper aims to assess the results of a pilot training project conducted in primary schools during November 2008 in Ramallah, Palestine, and April 2009 in Al-Salt, Jordan. In addition, the paper looks at the essential challenges involved in developing the programme on a national scale in Jordan and Palestine, incorporating it into the official curriculum, and evaluating its local impact with the overall aim of more effective and equitable use and allocation of water resources.

Municipal wastewater treatment by sequential combination of photocatalytic oxidation with constructed wetlands

Aim of the present work is the study and the experimental evaluation of an alternative and innovative wastewater treatment system, which combines the action of photocatalytic oxidation with the surface flow constructed wetlands. This low cost and environmental friendly system is based on the utilization of solar irradiation and natural processes for wastewater treatment purposes. Experiments were conducted at laboratory scale using artificial as well as solar irradiation, for the treatment of both synthetic and cesspool wastewater. The data evaluation revealed that the combined system may effectively reduce the organic load, the nutrients, as well as the pathogenic bacteria of wastewater, even in cases of great inflow variability, in terms of hydraulic and organic load, and thus may be proven a promising solution for municipal wastewater treatment in the near future.

Correlation between hydroxyl radical production and theoretical pressure distribution in a sonochemical reactor

The effects of operational parameters upon the hydroxyl radical generation of sonochemical reactors are critical to optimize this technology for wastewater treatment purposes. Ultrasonic wave characteristics are usually considered as the main parameter to be taken into account. Nevertheless, it is the interaction of these waves with the liquid medium and the reactor what really affects the process. Therefore, the characterization of sonochemical reactors should be based on the effective pressure distribution in the reactor, which not only includes the wave characteristics but also the propagation and reflection of these ultrasonic oscillations. The pressure field can be characterized using different parameters, such as maximum pressure amplitude or volumetric integration of pressure in the reactor. This study intends to find a correlation between such calculated pressure-distribution-related parameters and experimental measurements of hydroxyl radicals in the process. Both experiments and calculations are run varying the tip-bottom distance (keeping the rest of parameters constant), creating different reflection effects with the reactor walls and therefore different pressure distributions across the reactor. The hydroxyl radical measurements are performed with salicylic acid dosimetry, applying a specific developed method for biphasic cavitating systems. On the other hand, the pressure distribution was calculated simulating the different configurations with the computational tool COMSOL.

Salicylic acid dosimetry applied for the statistical determination of significant parameters in a sonochemical reactor

The effects of operational parameters upon the hydroxyl radical generation of sonochemical reactors are critical to optimize this technology for wastewater treatment purposes. Salicylic acid dosimetry, due to its chemical and physical properties, is a very adequate method to characterize a sonochemical reactor by indirect determination of the OH radicals generated in the cavitating process. The degradation products, 2,5-dihydroxybenzoic acid (2,5-DHB) and 2,3-dihydroxybenzoic acid (2,3-DHB), are specific and easily determined with HPLC methods. The most significant parameters were determined by designing a 2 5 factorial set of experiments and applying some statistical tools to the results obtained with the dosimeter. When operating within a limited range (typical range of standard sonochemical reactors) the statistical tools showed that only the dosimeter concentration and the reactor geometry were mathematically significant in the process.