Separation/stabilization of selected heavy metals from water and soil using waste seashells

Ubrzani industrijski razvoj doveo je do globalnih problema iscrpljivanja prirodnih resursa, zagađenja životne sredine, generisanja i akumulacije otpada. Ljušture školjki, poreklom iz prehrambene industrije, koje se u milionima tona generišu svake godine, deponuju se u priobalnim područjima gde negativno utiču na celokupnu životnu sredinu. Kao sekundarni izvor kalcijum karbonata, ovaj materijal predstavlja potencijalnu zamenu za prirodni krečnjak, čija je dostupnost ograničena. Otpadne ljušture školjki imaju široku primenu u oblastima kao što su: tretman vode i zemljišta različitog stepena zagađenja, ishrana domaćih životinja, proizvodnja gume, boja, farmaceutskih proizvoda...Global industrial development has led to the fast depletion of natural resources, environmental pollution, and waste generation and accumulation. The seafood industry generates millions of tons of mollusc shells, which are deposited in coastal areas with negative effects on the entire environment. As a secondary source of calcium carbonate, seashells are a potential substitute for limestone, which availability in nature is limited. Waste seashells are already being applied in different areas, such as wastewater and soil treatment, animal feed production, pharmaceuticals, paint, and rubber production..

Copper sorption capacity of the soil treated with unconventional alkalizing agents

The influence of unconventional alkaline additives (ground seashells and bauxite residue) on the copper (Cu) sorption and retention capacity of acidic soil was investigated. The soil collected near the mining and metallurgical complex in Bor (Serbia) was treated with different doses of additives, and the Cu sorption and desorption were assessed in batch conditions. The waste-derived materials proved to be efficient and sustainable alternatives to conventional alkalizers, increasing the maximum sorption capacity for Cu in correspondence with the soil pH increase. Nevertheless, added Cu was largely mobilized by weak acid extraction, demonstrating the importance of maintaining optimal soil pH for Cu leaching prevention

Comparative assessment of zinc ions sorption and retention by prospective unconventional soil additives

Mining, combustion of coal and waste, and steel processing are the main industrial activities that trigger the emission of large amounts of Zn, which reach the soil and pose a risk to its services, functions, and groundwater quality. A frequently associated process is soil acidification, reducing soil's ability to retain incoming toxic metals. The soil treatments with reactive, low-cost, and locally available materials might be a straightforward approach to decreasing the mobility of toxic metals and alleviating the environmental risks. This study aimed to compare Zn ions sorption and retention by several unconventional soil additives (seashell waste, bone char, and red mud) against the performance of acidic soil. Batch experiments of Zn ions sorption were initially performed using solutions with different Zn concentrations, followed by the determination of sorbed Zn stability in an acidic medium. The waste materials exhibited higher pH values and superior Zn sorption capacities with respect to the soil. The desorption experiment exposed different mechanisms of Zn ions fixation by studied materials. While the substantial amounts of Zn sorbed by seashells, red mud, as well as soil were released in the scope of the ion exchange and carbonate fraction, sensitive to pH decrease, the bone char preserved Zn in more stable fractions. The investigated waste materials can potentially prevent Zn leaching through the soil profile, with the bone char demonstrating the most significant capability for long-term retention performance

Fabrication of Porous Anorthite Ceramic Insulation Using Solid Wastes

Porous anorthite (CaAl2Si2O8) ceramics, suitable for thermal insulation in buildings, were obtained using waste seashells as a source of CaO, kaolin as a source of Al2O3 and SiO2 and banana peel as a pore former. Changing the volume of banana peel as well as the processing temperature was found to be an effective approach to control the thermo-mechanical properties of the obtained anorthite ceramics. The sintering of powder compacts containing up to 30 wt% banana peel at temperatures ranging from 1100 to 1200 °C resulted in anorthite ceramics possessing up to 45% open porosity, a compressive strength between 13 and 92 MPa, a bulk density between 1.87 and 2.62 g/cm3 and thermal conductivity between 0.097 and 3.5 W/mK. It was shown that waste materials such as seashells and banana peel can be used to obtain cost-effective thermal insulation in buildings

Changes in concentration of DTPA-extractable forms of metals in response to soil treatment with variable seashell doses

Seashells piled in coastal areas worldwide, particularly near commercial mollusk farms, may pose a substantial environmental and health risk. Utilizing seashell waste (SW) as a natural liming material represents a meaningful contribution to the sustainable development of the aquaculture industry through resource recovery. This study assessed the effects of adding various doses of finely ground SW to acidic agricultural soil with elevated total concentration of Cu (219.2 mg/kg) on the bioavailability of selected metals (Cu, Zn, Fe, Mn, Co, Pb, Ni, and Cd). The concentration of DTPA-extracted forms of Cu and other elements decreased significantly with the increase in SW dose from 0.15% to 2%, whereas differences between 2% and 5% treatments were not significant. The association of metals' bioavailability with the agrochemical properties of control and treated soil samples revealed the leading influence of soil pH. Furthermore, the DTPA-extracted amounts of Cu and Zn were negatively correlated with carbonate and organic carbon content, and bioavailable Zn forms were negatively correlated with the content of accessible phosphorus. As a cost-effective, sustainable, and renewable source of calcium carbonate, organic carbon, and available phosphorus, SW is a candidate material for acidic soil amelioration, including the immobilization of a range of toxic and potentially toxic metals. However, the study's results underline that SW dose optimization through preliminary tests is a necessary research component that requires observing soil fertility parameters, particularly the status of essential metals

Uklanjanje hroma(VI) iz vode primenom praškastog ugljeničnog materijala dobijenog iz kokosove ljuske kao jeftinog adsorbenta

Most heavy metals, such as Cr (chromium), Pb (lead), Cd (cadmium), Ni (nickel), Cu (copper) and Fe (iron), are extremely toxic above a tolerance limit. These heavy metals in wastewater are not biodegradable and can cause serious harm to human health and ecological environments.1 One of the top-priority toxic heavy metal in wastewater is chromium.2 In natural waters, chromium exists in both trivalent Cr(III) and hexavalent Cr(VI) forms. Cr(VI) is the most toxic one and have the tolerance limit 0.1 mg/L into surface water and 0.05 mg/L in potable water.3 Various methods, such as ion exchange, sedimentation, electrochemical process, cementation, coagulation, adsorption and solvent extraction have been developed for the removal of Cr(VI) and other toxic metals from wastewater.4 Among these methods, in some papers,5-8 adsorption has been used as one of the most effective method for the removal of Cr(VI) from aqueous solutions. Characteristics of adsorption, such as low cost, easy to perform, efficient and reversible method with high operating speed, make this method as most commonly used for the removal of Cr(VI) from aqueous solutions.9 Several adsorbents, like activated alumina,10 zeolites,11 natural bisorbents such as chitosan,12 but also activated carbon13 have been used for the removal of Cr(VI) from aqueous solutions. Due to the high cost, commercial activated carbon is not available in less developed countries and there is a considerable attention to produce activated carbon from less expensive and available materials. As a low-cost adsorbent, activated carbon can be produced from materials such as rice husk, seeds husk, tea leaves, sawdust, oil palm shell, coconut husk and coconut shell.14 Activated carbon is one of the most important adsorbents which is applied in different areas. In these areas it is important to determine and remove low concentrations of some pollutants, such as heavy metals. Very good features of this adsorbent are the main reason why it is used, such as large surface area, porous structure, high adsorption capacity, selective adsorption and low cost. Also, it is important to note that activated carbon has microcrystalline structure with different size and shape of pores, while surface groups plays important role in the adsorption process. Carbon - oxygen surface groups are the most important and they influence the surface characteristics, such as polarity and physicochemical properties of adsorbent. There are two processes for preparation of activated carbon, chemical activation which involves presence of chemical agents, and physical activation, which involves carbonization.15-16 For this research, low-cost powdered activated carbon made from coconut shell was used as adsorbent to remove Cr(VI) from aqueous solutions. Characterization of activated carbon, produced from coconut shell, was accomplished using scanning electron microscopy (SEM) and Brunauer-Emmett-Teller (BET) method. The effects of three 57. savetovanje SHD 137 adsorption parameters, such as solution pH, contact time and initial Cr(VI) concentration, were investigated with respect to the removal efficiency of Cr(VI) from aqueous solutions. Adsorption equilibrium characteristics were analyzed by using the two adsorption models, namely the Langmuir and the Freundlich isotherms.Praškast ugljenični materijal proizveden iz kokosove ljuske korišćen je kao adsorbent za uklanjanje Cr(VI) jona iz vodenih rastvora. Karakterizacija adsorbenta rađena je primenom dve analitičke tehnike, skenirajućom elektronskom mikroskopijom (SEM) i BET metodom. Eksperimenti adsorpcije rađeni su u šaržnom režimu, kako bi se istražili uticaji pH rastvora, vremena kontakta i početne koncentracije Cr(VI) jona. Eksperimentalni rezultati su pokazali da je efikasnost uklanjanja Cr(VI) najveća u pH intervalu od 2,0 do 3,5, a da se ravnoteža uspostavlja nakon 60 minuta. Dva ravnotežna adsorpciona modela, Langmirov i Frojndlihov, korišćena su za fitovanje dobijenih podataka. Frojndlihova izoterma je obezbedila najbolju korelaciju za adsorpciju Cr(VI) jona na ugljeničnom materijalu proizvedenom iz kokosove ljuske. Na osnovu dobijenih rezultata može se zaključiti da ugljenični materijal proizveden iz kokosove ljuske predstavlja jeftin i efikasan adsorbent koji bi potencijalno mogao biti korišćen za tretman otpadnih voda koje sadrže toksični Cr(VI).57th Meeting of the Serbian Chemical Society; June 18-19, Kragujevac, Serbi

Mn bioavailability in soil after in situ remediation with apatite additive

Primena apatitnih materijala kao aditiva kontaminiranom zemljištu jedna je od intenzivno proučavanih metoda in situ stabilizacije radionuklida u zemljištu. Istraživanja uticaja tretmana na distribuciju Mn u zemljištu i njegovu biodostupnost su posebno interesantna, s obzirom da je ovaj element esencijalan za biljke. U ovom radu ispitan je efekat različitih doza biogenog apatita (0,3%, 2% i 5%) kao aditiva kiselom zemljištu, na frakciju biodostupnog Mn hemijski ekstrahovanog metodom DTPA, kao i na sadržaj Mn u nadzemnom delu biljke Lolium perenne gajene u pot-eksperimentima na netretiranom i tretiranom zemljištu. Ustanovljeno je da se sa povećanjem količine dodatog bioapatita smanjuje koncentracija Mn u DTPA ekstraktu, kao i u nadzemnom tkivu biljke. Hemijski ekstrahovane i biološki usvojene koncentracije Mn su međusobno bile u pozitivnoj korelaciji (R2=0,971, p<0,05). U svim varijantama tretmana DTPA ekstrakt je sadržao koncentracije Mn u granicama koja se smatraju adekvatnim za većinu biljnih kultura.The use of apatite materials as additives to contaminated soil is one of the intensively studied in situstabilization methodforradionuclides in thesoil.Investigation of the treatment effects on the Mn distribution in the soil and its bioavailability are particularly interesting, since this element is essential for plants.In this paper, the effect of various doses of biogenic apatite (0.3%, 2% and 5%) as an additive to acid soil, was investigated in relation to the bioavailable Mn fractionchemically extracted by DTPA methodand to the Mn content in the above-ground part of the Lolium perenneplant, cultivated on untreated and treated soils in pot experiments. It was found that the increase in the amount of added bioapatite decreases the concentration of Mn in the DTPA extract, as well as in the above-ground tissue of the Lolium perenneplant.Chemical extracted and biologically accepted Mn concentrations were in positive correlation (R2= 0.971, p <0.05).In the all treatment variants, the DTPA extractscontained Mn concentrations within the limits considered to be adequate for most plant cultures.Proceedings: [http://vinar.vin.bg.ac.rs/handle/123456789/8681]XXX симпозијум ДЗЗСЦГ (Друштва за заштиту од зрачења Србије и Црне Горе), 2- 4. октобар 2019. године, Дивчибаре, Србиј

Black inorganic pigments obtained from waste materials

Hazardous industrial wastes are the most common source of environmental pollution. Waters originating from unregulated landfills and places of inadequate disposal of this type of wastes can pollute the water sources and affect the human health. In this study, electroplating waste sludge (ES) and various Fe-rich wastes were used as starting materials for the synthesis of inorganic pigments. Obtained black Cr1.3Fe0.7O3 pigments possess adequate properties required for use as inorganic pigments

Gamma Irradiation Induced Dyes Degradation: Recent Progress and Future Perspective for Wastewater Treatment

Program and book of abstracts / 2nd International Conference on Innovative Materials in Extreme Conditions i. e. (IMEC2024), 20-22 March 2024 Belgrade, Serbia

Fabrication of porous anorthite-based ceramics using solid wastes for costeffective thermal insulation of buildings

There is a global tendency to reduce the consumption of energy required for heating as well as cooling buildings. Therefore, thermal insulation technology becoming important in preventing both, the gain and loss of heat through the building envelope. This work aims to evaluate the feasibility of using inexpensive raw materials such as kaolin and waste material such as seashells and banana peel for fabrication of the sustainable anorthite-based porous ceramics for thermal insulation. Kaolin was used as a source of Al2O3 and SiO2, seashells as a source of CaO whereas banana peel was used as a pore former. The phase composition, bulk density, open porosity, compressive strength, microstructure, and thermal conductivity of the ceramic samples, were analyzed. The obtained results showed that the variation of pore former (banana peel) content and sintering temperature was an effective way to control the thermo-mechanical properties of the obtained anorthite ceramics. Samples with open porosity (1.4 – 45%), compressive strength (>15 MPa), bulk density (1.87-2.62 g/cm3 ), and thermal conductivity (0.097-3.67W/mK) were obtained after sintering of samples with different percent of banana peel at 1100–1200 ◦C. It suggests that the obtained porous ceramics can be used for cost-effective thermal insulation of buildings.XI Serbian Ceramic Society Conference - Advanced Ceramics and Application : new frontiers in multifunctional material science and processing : program and the book of abstracts; September 18-20, 2023; Belgrad