Review of biodiesel production by the esterification of wastewater containing fats oils and grease (FOGs)

open access articleA promising solution for the near future is the substitution of non-renewable fossil fuels with a sustain able liquid feedstock for biofuel (biodiesel) production. The cost of conventional biodiesel production is higher than that of petroleum-based diesel production since it is produced mostly from expensive high quality virgin oil. 70–80% of the overall biodiesel production cost is associated with the cost of raw mate rials. Brown grease (with free fatty acid levels > 15%) is created from rendered trap waste and is known as Fats, Oils, and Greases (FOGs). It is a potential source of biodiesel feedstocks and is available at no cost. Many researchers are interested in using low-cost high Free Fatty Acid (FFA) oils as the feedstock for bio diesel production. This paper reviews the effect of feedstock pre-treatment and process parameters on the conversion of FOGs-wastewater to biodiesel by esterification, including alcohol to oil molar ratio, reaction temperature, reaction time, catalyst amount

Esterification of stearic acid using novel protonated and crosslinked amidoximated polyacrylonitrile ion exchange fibres

open access articleThis study will demonstrate the conversion of stearic acid to methyl stearate (biodiesel) using for the first time crosslinked amidoximated polyacrylonitrile ion-exchanged mesh protonated by sulphuric acid. Quantitative analysis of conversion was by GC-FID, 1H NMR and ATR-FT-IR with GC-FID the most reliable. A molar ratio of methanol to stearic acid of 35.5: 1 gave 94 % conversion to the ester at 90 C. At 65 C and a greater ratio of 87.1:1 conversion was 94.1 % comparable to the 98 % yield obtained with 1wt% H2SO4. Re-use at 65 C gently dropped to 57 % on the 13th cycle. Regeneration by washing with dichloromethane and re-acidification achieved 84 % conversion but quickly deactivated due to blocking of sites by methyl stearate as shown by ATR-FTIR. This protonated amidoxime PAN catalyst (distinct from sulfonated fibres) exhibited higher stability than other heterogeneous protonated catalysts (ion-exchange resins, zeolites, clays) used lower temperatures and shorter reaction times. Advantages of using a mesh in place of powders are its ease of removal/replacement for continuous flow reactors promoting quick changes in process parameters. This study is promising as providing a sustainable protonated catalyst for use in converting Fats, Oils and Greases (FOG’s) in waste oils and wastewater to biodiesel. 2022 The Authors. Published by Elsevier B.V. on behalf of The Korean Society of Industrial and Engineering Chemistry. This is an open access article under the CC BY-NC-ND licens

Heterogeneous Fenton's-like catalysis for degradation of colchicine coupled with extraction of its biologically active metabolite

Work performed in Professor Huddersman's laboratory at De Montfort University by visiting Researcher (academic lecturer) from Faculty of Pharmacy, Assiut University, Egypt The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI link.Nowadays, drug pollution; a form of water pollution caused by some pharmaceuticals and their metabolites resulting from consumers, industry and hospitals was reported. Colchicine (CLN) is considered one of the pharmaceutical wastewater contaminants which are not eliminated completely in municipal sewage treatment plants and are discharged into receiving water. Due to the higher toxicity of CLN, a novel heterogeneous Fenton's-like catalysis was established for complete degradation of CLN. So, a highly sensitive and specific liquid chromatographic method with quadrupole mass spectrometry (LC/Q-MS) was developed and validated for estimation of CLN in its pure form and in the presence of its degradation product. Herein, GraceSmart RP C18 column was utilized for separation of the cited drug (Retention time tR= 5.578 min) using methanol: water (55: 45, v/v) at 1.0 mL/min. Detection was performed by Agilent 6120 Quadrupole MS detector in a positive ionization mode. Thereafter and for the first time, degradation of CLN by heterogeneous Fenton's-like catalysis using modified polyacrylonitrile (PAN) as a catalyst with H2O2 in aqueous acidic medium was performed. This process was firstly optimized by HPLC/UV detection at 248 nm using the aforementioned chromatographic conditions. As a result, CLN degraded completely within 30 min. The only observed degradation product was the biologically active, potent and less toxic antitumor metabolite of CLN (3- demethyl CLN) which was collected, extracted, and analyzed by Fourier Transfer- Infrared Spectroscopy (FTIR) and 13Carbon- Nuclear Magnetic Resonance (13C-NMR). Finally, this method is eco-friendly and complies with the requirements of the green chemistry. It is suitable for complete removal of CLN and/or its metabolite contaminants from wastewater samples and estimation of the target drug without any interference from its degradation products. However, further study is required to expand the method applicability to the pharmaceutical wastewater treatment as well the production of 3- demethyl CLN on a large scale

Multivariate analysis of the effects of age, particle size and landfill depth on heavy metals pollution content of closed and active landfill precursors

The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI link.Multivariate analysis of a heavy metal pollution survey of closed and active landfill precursors was carried out in order to compare environmental risk levels in relation to age, particle size and depth of the precursors. Landfill precursors (77) were collected and analyzed for 15 USEPA toxic heavy metals using ICP-MS. Heavy metals concentrations in closed landfill precursors were significantly higher than those in the active landfill for 11 of 15 heavy metals investigated (closed landfill order: Fe > Al > Mn > Cu > Pb > Ba> Co > Cr > Ni > Cd > As > Se > Ti). Cluster analysis and correlation studies indicated the distribution of the metals was more influenced by landfill precursor size than by depth of the sample. Principal component analysis (PCA) showed that 10 of 15 of heavy metals of both landfill precursors were from similar anthropogenic sources. Heavy metals pollution indices (Igeo > 5, EF > 40 and CF > 7) of both active and closed landfill precursors exceeded limits in the order of Zn > Cd > Pb > Cu > Ag, indicating a major potential health risk influenced by age and particle size of precursor. Zn, Cd, Cu and Pb of both landfill precursors exceeded the USEPA set standard for assessment of human health risk for each of the metals (1×10 -4 to 1× 10-3). This study highlights the need for the integration of a clean-up process for precursors from both types of landfill to reduce possible environmental pollution during a reuse process

Chitosan-terephthalic acid-magnetic composite beads for effective removal of acid blue dye from aqueous solution; kinetics, isotherm and statistical modeling

open access articleA terephthalic acid-modified chitosan−magnetic nanocomposite (Cs−Tp@Fe3O4) was synthesized and characterized. The synthesized Cs−Tp@Fe3O4wasused in a batch process for the adsorptive removal of the acid blue 25 (AB-25) dye inaqueous solutions. The kinetic data were subjected to the pseudo-first-order, pseudo-second-order, Elovich, and intra-particle diffusion models, while the equilibrium datawere evaluated with the Langmuir, Freundlich, Temkin, and Dubinin−Radushkevichisotherm models. The effects of the initial dye concentration, contact time, andadsorbent dosage, as well as their interactions, on the removal efficiency wereinvestigated using the design of experiments based on a central composite design, andthe resultant data were modeled with the response surface methodology (RSM),artificial neural network (ANN), adaptive neuro-fuzzy inference system (ANFIS), andmultiple linear regression (MLR) approaches. The adsorption process followedpseudo-first-order with good agreement between the experimentalQe(exp)andcalculatedQe(cal.)amounts of dye adsorbed, as well as the values of correlation coefficient,R2(0.999) and percentage of sumsquare error, % SSE (0.640). All the investigated adsorption isothermsfitted all models well in the order of Dubinin−Radushkevich> Langmuir > Freundlich > Temkin withR2> 0.9 with the monolayer maximum adsorption capacity of 440.24 mg/g obtained fromthe Langmuir isotherm. The RSM model predicted the maximum removal efficiency at an optimum initial dye concentration of19.11 mg/L, a contact time of 95.3 min, and an adsorbent dosage of 0.18 g. Statistically, the models werefitted in the order of RSM> ANN > ANFIS > MLR. These results indicated that the prepared Cs−Tp@Fe3O4is an efficient adsorbent for the AB-25 dyeremoval with excellent stability for water treatment applications. (8) (PDF) Chitosan–Terephthalic Acid–Magnetic Composite Beads for Effective Removal of the Acid Blue Dye from Aqueous Solutions: Kinetics, Isotherm, and Statistical Modeling. Available from: https://www.researchgate.net/publication/355954648_Chitosan-Terephthalic_Acid-Magnetic_Composite_Beads_for_Effective_Removal_of_the_Acid_Blue_Dye_from_Aqueous_Solutions_Kinetics_Isotherm_and_Statistical_Modeling [accessed Nov 25 2021]

Conversion of solid waste to activated carbon to improve landfill sustainability

The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI link.Landfills’ heterogeneous composites waste were evaluated as precursors for generation of activated carbon (AC). A single step chemical activation process was applied involving irradiation with microwave energy and impregnation with KOH. The average percentage yield of AC from active landfill precursor was higher than that from closed landfill for all depths sampled. Increase in impregnation ratio and irradiation power decreased the average percentage yield for both landfill precursors (Active: 38.1 to 33.1%) (Closed 42.1: to 33.3%). The optimum pH range for adsorption of methylene blue was pH 6-7, while adsorption increased with increase in temperature over the range 30 to 50oC. Carbonyl and hydroxyl groups were the major functional groups on the surface of AC. The properties of the AC are potentially suitable for the removal of cationic dyes and pollutants. AC generated from the landfill composite were comparable to that from some other biomass being managed through AC generation. This is the first report to demonstrate the possible reuse of landfill composite as AC. The reuse option of landfill composite could provide a means of sustainable management of landfilled municipal waste

Advance Oxidation Process (AOP) of Bisphenol A Using a Novel Surface-Functionalised Polyacrylonitrile (PAN) Fibre Catalyst

Open access articleBisphenol A (BPA) is a well-known endocrine disruptor in the environment which is not readily oxidised during wastewater treatment at Municipal Authorities. The aim of this work is to evaluate the environmental value of the wastewater treatment of a novel heterogeneous oxidation catalyst by means of the degradation of BPA, avoiding sewage sludge and its post-treatments. A surface-functionalised polyacrylonitrile (PAN) mesh has been produced by reaction of the cyano group of PAN with hydrazine and hydroxylamine salts. This surface-functionalised PAN is then exposed to iron (III) salt solution to promote the ligation of Fe(III) to the functional groups to form the active catalytic site. The experiments were set up in two different batch reactors at laboratory scale at different temperatures and initial pH. The degradation of BPA was detected by measuring the absorbance of BPA in Reverse Phase High Performance Liquid Chromatography at 280 nm. A total elimination of 75 ppm of BPA in less than 30 min was achieved under 300 ppm H2O2 , 0.5 g PAN catalyst, initial pH 3 and 60 ◦C. Almost no adsorption of BPA on the catalyst was detected and there was no significant difference in activity of the catalyst after use for two cycles

Novel fibrous catalyst in advanced oxidation of photographic processing effluents

This paper is one of a series of papers describing applications of the catalyst to the removal of organics from waste water. Other papers are devoted to dye bath effluent from textile houses (e.g. William Baker). In this paper waste water from Kodak containing a concentrated mixture of organic and inorganic compounds was decomposed by the catalyst at room temperature by optimising the process conditions. It confirmed that the catalyst was not poisoned by other compounds present in “real” effluent again facilitating potential industrial take-up. Kodak is now moving to digital photographs reducing the need to treat waste water