Nanocarbons from acid pretreated waste coffee grounds using microwave radiation

This study investigates the use of microwave radiation to produce nanocarbons from Waste Coffee Grounds (WCG). It is first step to demonstrate the potential of integrating the microwave power to conventional methods of carbonaceous materials and nanocarbons production, aiming to overcome their high production cost. The process parameters and interactions investigated were: microwave radiation power (W), temperature (°C) and residence time (min). Results obtained from the lab-scale experiments indicated the optimum conditions for maximizing the nanocarbons yield (wt%) from the H₂SO₄ acid pretreated WCG at 200 °C, 850 for 60 min resulting in a 87.6 wt% char yield which ranged between the average size of 100–140 nm and lower. Moreover, the optimum conditions to achieve the maximum yield of nanocarbons (wt%) where: same temperature (200 °C), lower microwave power (650 W) and residence time (45 min). Then a yield of 60 wt% nanocarbons of average sizes 60 nm were produced, indicating the potential of this method to produce value-added biomaterials (spherical shaped nanocarbons) applicable for future scientific breakthroughs

Green tea polyphenol-reduced graphene oxide: derivatisation, reduction efficiency, reduction mechanism and cytotoxicity

This paper reports on the derivatisation, reduction efficiency, reduction mechanism and cytotoxicity of green tea polyphenol-reduced graphene oxide (GTP-RGO). The reduction of graphene oxide (GO) at 90°C using a weight ratio (WR) of GTP/GO=1 resulted in the production of a stable GTP-RGO dispersion in aqueous media, as indicated by the results of ultravioletvisible (UV-Vis) spectroscopy, Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA) and the measurement of zeta potential and electrophoretic mobility. In addition, the results from UV-Vis spectroscopy and X-ray photoelectron spectroscopy (XPS) analysis indicated the comparable reduction ability of GTP relative to the standard reducing agent, hydrazine (N2H4). The removal mechanism of epoxy group from GO via reduction reaction with GTP was investigated by implementing hybrid functional method of Becke-3-parameters-Lee-Yang-Parr (B3LYP)using Gaussian 09 software. The energy and frequency calculations showed that the GO reduction using GTP was more spontaneous and relatively took place faster than the reduction using N2H4, as evidenced by higher entropy change (ΔS) (0.039 kcal/mol·K) and lower Gibbs free energy (ΔG) barrier (58.880 kcal/mol).The cytotoxicities of GO and GTP-RGO samples were evaluated against human colonic fibroblasts cells (CCD-18Co). The GO sample was determined to be toxic even at low concentration (6.25 μg/mL), while the GTP-RGO sample possesses notably low toxicity at the same concentration. The cell culture experiments revealed that the incorporation of GTP led to a decrease in the toxicity of GTP-RGO samples

Techno-Economic Analysis and Feasibility of Industrial-Scale Activated Carbon Production from Agricultural Pea Waste Using Microwave-Assisted Pyrolysis: A Circular Economy Approach

This paper examines a novel approach to activated carbon (AC) production that uses pea waste (PW) and to what extent it is economically competitive with current production methods. Additionally, the outcome is to provide a detailed economic analysis to understand whether this process is viable. The focus of this production route and the economic analysis will be on a United Kingdom (UK) basis. The plant will be located within the north UK to minimise storage and transportation costs. It also has extensive links to other clusters of nearby industries that would produce from this process in air pollution control or wastewater treatments. The overall production process is detailed, and detailed equipment specifications, including the sizing of equipment and utility requirements, were also given. Material balance calculations are carried out to assess the performance and improve process design. An economic analysis is performed to study the potential of biomass-to-AC conversion costs and commercialisation viability. The project’s investment is about £100 million. The cost of the plant can be recovered from year 3 (mid) for the 20-year life of the plant. The Net Present Value (NPV) is based on cumulative cash flow. The NPV is calculated as GBP 4,476,137,297.79 for 2020, and the associated internal rate of return (IRR) and the return on investment (ROI) for the project are 55% and 52%, respectively

Industrial-Scale Activated Carbon Production from Agricultural Pea Waste: A Techno-Economic and Feasibility Study

This paper examines a novel approach to activated carbon (AC)production that uses pea waste (PW) and to what extent it iseconomically competitive with current production methods.Additionally, the outcome is to provide a detailed economicanalysis to understand whether this process is viable. The focusof this production route and the economic analysis will be on aUnited Kingdom (UK) basis. The plant will be located withinthe north UK to minimise storage and transportation costs. Italso has extensive links to other clusters of nearby industries thatwould produce from this process in air pollution control orwastewater treatments. The overall production process isdetailed, and detailed equipment specifications, including thesizing of equipment and utility requirements, were also given.Material balance calculations are carried out to assess theperformance and improve process design. An economicanalysis is performed to study the potential of biomass-to-ACconversion costs and commercialisation viability. The project’sinvestment is about £100 million. The cost of the plant can berecovered from year 3 (mid) for the 20-year life of the plant.The Net Present Value (NPV) is based on cumulative cash flow.The NPV is calculated as GBP 4,476,137,297.79 for 2020, andthe associated internal rate of return (IRR) and the return oninvestment (ROI) for the project are 55% and 52%, respectively

Latest Advances in Waste Plastic Pyrolytic Catalysis

With the increase in demand for plastic use, waste plastic (WP) management remains a challenge in the contemporary world due to the lack of sustainable efforts to tackle it. The increment in WPs is proportional to man’s demand and use of plastics, and these come along with environmental challenges. This increase in WPs, and the resulting environmental consequences are mainly due to the characteristic biodegradation properties of plastics. Landfilling, pollution, groundwater contamination, incineration, and blockage of drainages are common environmental challenges associated with WPs. The bulk of these WPs constitutes polyethene (PE), polyethene terephthalate (PET) and polystyrene (PS). Pyrolysis is an eco-friendly thermo-chemical waste plastic treatment solution for valuable product recovery, preferred over landfilling and incineration solutions. In this extensive review, a critical investigation on waste plastic catalytic pyrolysis (WPCP) is performed, including catalyst and non-catalyst applications to sustainably tackle WP management. Current catalysis techniques are revealed, and some comparisons are made where necessary. Common pyrolytic products and common shortcomings and errors related to WP catalysis were also identified. The benefits of catalysts and their applications to augment and optimise thermal pyrolysis are emphasised. With all these findings, and more, this paper provides reassurance on the significance of catalysis to industrial-scale applications and products and supports related WPCP research work concerning the environment and other beneficiaries

Recent Advances on Waste Plastic Thermal Pyrolysis: A Critical Overview

Post-consumer plastic management, otherwise termed waste plastic (WP) management, is a great challenge in today’s world, mainly because of its characteristic biodegradation properties. The quantity of waste plastics correspondingly increases with the increase in demand for plastic use. Research has shown that this demand increases yearly. Most of these waste plastics include high-density polyethylene (HDPE), low-density polyethylene (LDPE), polyethylene terephthalate (PET) and polystyrene (PS). Potentially, these wastes are a wealth, and studies have explored that pyrolysis is a reputable mechanism to accomplish this. In this critical review, an extensive investigation on waste plastics thermal pyrolysis (WPTP) is carried out. The factors that affect the product’s yield and selectivity are discussed, and a comparative quality guarantee of WPTP is examined. This paper presents an assurance into the current findings of WPTP and reveals some common gaps and misconceptions surrounding this field, which are recommendable towards the support of further research work. The significant role of co-pyrolysis of plastics with biomass in this field is also emphasised, and a glimpse into the influence of mixed waste plastics in pyrolysis is presented

Pengaruh Konsentrasi Serbuk Majemuk Biji Sarikaya Dan Biji Sirsak Terhadap Mortalitas Kumbang Beras Sitophilus Oryzae L. (Coleoptera : Curculionidae) Di Penyimpanan

This research aims to determine the effect of compound seed powder sugar apple and soursop seed against S. oryzae mortality in storage. The study was conducted from January to April 2016 at the Laboratory of Plant Pests and Diseases Departement, Faculty Agriculture, Tadulako University Palu. Materials used seeds soursop (Annonamuricata L.) seeds and sugar apple seeds (Annonasquamosa L.), aquadestand local varieties of rice. The study design using a completely randomized design consisting of 6 treatments with 3 replications level namely P0: Control without giving samples; P1: 1g/200g of rice; P2: 2g/200g of rice; P3: 3g/200g of rice; P4: 4g/200g of rice); P5: 5g/200g of rice. The analysis uses a test of variance and to determine the best treatment to use honest significant difference test α level of 0.05. The results showed that the compound powder sugar apple seed and seed soursop affect the rice beetles mortality. The most effective concentration causing mortality in rice beetles that is on the treatment of P2 concentration of 2g/200g of rice with a percentage of56.67%.The concentration was significantly different with the treatment of P3, P4, P5 each concentration 3g/200g, 4g/200g, 5g/200g rice with percentage mortality 81.11%, 92.22%, and 100.00% respectively

Future scope and directions of nanotechnology in creating next-generation supercapacitors

The primary global research scheme of the 21st century is nanotechnology. Looking forward to the future, nanotechnologies’ generalized diffusion will seem to turn them into supplies, generating more space for privileged and superior values of applications such as information technology, nanoenergy, nanobiotechnologies, and nanomaterials.1-5 In general, nanotechnology is the understanding and controlling of the matters of dimensions of approximately 1-100 nm, in which a unique phenomenon facilitates novel applications.2 The application domains covered by nanotechnology are discussed in detail in this chapter