Cocoa husk is considered a waste product after cocoa processing and creates environmental issues. These waste products are rich in polyphenols, methylxanthine, dietary fibers, and phytosterols, which can be extracted and utilized in various food and health products. Cocoa beans represent only 32–34% of fruit weight. Various extraction methods were implemented for the preparation of extracts and/or the recovery of bioactive compounds. Besides conventional extraction methods, various studies have been conducted using advanced extraction methods, including microwave-assisted extraction (MAE), ultrasonic-assisted extraction (UAE), subcritical water extraction (SWE), supercritical fluid extraction (SFE), and pressurized liquid extraction (PLE). To include cocoa husk waste products or extracts in different food products, various functional foods such as bakery products, jam, chocolate, beverage, and sausage were prepared. This review mainly focused on the composition and functional characteristics of cocoa husk waste products and their utilization in different food products. Moreover, recommendations were made for the complete utilization of these waste products and their involvement in the circular economy.

In the present work, pollutant removal study of Century Pulp and Paper Mill effluent was done. A hybrid unit of upflow fixed-bed anaerobic bioreactor (UFBAB) along with slow sand filter (SSF) was compared with single unit UFBAB for pollutant removal at different hydraulic retention time (HRT). The hybrid system showed better removal efficiency which can be attributed to SSF. It was observed that SSF provides a polishing effect to the effluent treated by UFBAB. The biodegradation rate in both filters was observed to be increased in first six weeks of experiment, prior to the acclimatization of microbial communities. The relative removal efficiency of biological oxygen demand and chemical oxygen demand was found to between 0.90 and 0.99, respectively, at 24 h HRT, demonstrating very high removal efficiency of the hybrid system. The relative removal efficiency of total dissolved solids and total suspended solids was around 1 at 16 h HRT indicating 100% efficient and within the limits as prescribed by Central Pollution Control Board India (CPCB) for treated effluent discharge in surface water bodies. Best removal efficiency was observed in case of sulfate at low HRT of 8 h. Relative removal efficiency for phenols was found to be greater than 1 at 12 h HRT. SSF was found to be a suitable substrate for polishing of treated effluent of pulp and paper mill wastewater, demonstrating promising relative efficiency.

Forward osmosis (FO) is attracting worldwide attention as an emerging technology in the fields of power generation, water reuse, desalination, pharmaceuticals and food processing. Still, the critical challenge of finding a suitable draw solute for FO persists. Therefore the current research focuses on synthesizing hydrophilic magnetic nanoparticles (HMNPs) and systematically investigating their potential as draw solutes. HMNPs were synthesized using functional groups polyethylene glycol (PEG 400) and polyacrylic acid (PAA). These functional groups under different ratios with a metal precursor react by one-pot polyol and thermal decomposition methods respectively to give different diameter HMNPs. In addition the effect of different sizes of synthesized HMNPs was investigated for their recovery under an external magnetic field and reusability in FO performance. The physical properties and chemical compositions of the resultant MNPs are fully characterized. Transmission electron microscopy (TEM) analyses show the characteristics as spherical morphology with a narrow size distribution, and a mean size from 9 to 32.5 nm for PEG and 8 to 30 nm for PAA coated HMNPs depending on the ratio of the functional group and metal precursor. The PEG and PAA layer on the MNPs is confirmed by Fourier transform infrared (FTIR) analysis, and thermogravimetric analysis demonstrates a hydrophilic surface composition. The PEG and PAA coated HMNPs generate high osmotic pressures and exhibit good dispersibility in aqueous solutions. Water fluxes of >13 L m⁻² h⁻¹ are achieved across Hydration Technologies Inc. flat sheet membranes at a concentration of 0.05 M of HMNPs using deionized water as the feed solution. The HMNPs can be easily recaptured from draw solutions by applying an external magnetic field and recycling them back as draw solute in the FO process. The MNPs remain active after nine runs of recycling but with a total water flux decrease of 5% in PEG and 3% with each successive recycling due to slight aggregation, and reduced surface to volume ratio is observed. Results of the present study have demonstrated that PEG and PAA coated HMNPs can viewed as promising and potential draw solutes in the FO process.

Purpose: – The energy demand of growing population is on rise despite the fact that conventional energy reserves are limited and exhaustive in nature. To quench the ever-needing demand of energy, there is an urgent need to find out new energy options. In this regard, role of bioenergy plantation has gained enormous attention of scientist community all over the world. Biochar, a black pyrolysed carbonaceous product, is used as soil amendment and is reported to provide several benefits such as retention of nutrients in soil, better cation exchange capacity, soil carbon sequestration with better biomass yield. The paper aims to discuss these issues. Design/methodology/approach: – The present study investigated the effect of domestic waste water (grey water) as well as biochar in combination for above-ground biomass of Eucalyptus hybrid (clone 413) and Anthocephalus cadamba plantations under flooded irrigation. Findings: – Height, girth and above-ground biomass of both plantations increased significantly from control. Above-ground biomass of A. cadamba was observed to be better than Eucalyptus hybrid during initial period of establishment. After application of biochar, treatment WW+BBm was found to produce maximum above-ground biomass followed by treatment WW and WW+ BBg in both plantations system. Originality/value: – The present study encompassed a real sustainable approach for environmental management by integrating the use of waste water (source of nutrients) as well as biochar (a solid waste pyrolysed material that act as soil fertilizer, an efficient adsorbent as well as a sink for carbon sequestration) for the better biomass yield of bioenergy plantations.

The present paper deals with the organic loadings of grey water with its average and maximum flow rate on an hourly and daily basis generated from the residential colony of G.B. Pant University of Agriculture and Technology, Pantnagar, India. For reliable quantification, the study was conducted at the interval of 1 h for eight consecutive days in each season during the year 2012 to 2013. Following parameters viz biochemical oxygen demand (BOD), chemical oxygen demand (COD), nitrogen, phosphorus, and potassium analyses were used to calculate grey water pollutant load. The observed annual average organic pollutant loading in terms of BOD was found to be 29.44 kg/day with maximum load in the summer season. However, this organic loading at maximum flow rate basis (in peak hours) was varied seasonally from 55.3, 52.0, and 83.3 kg/day, respectively, during the monsoon, winter, and summer seasons. The grey water discharge flow rate reveals the need of a treatment system compatible with fluctuating pollutant loads. The bioefficacy of phytoremediation-based technology was assessed and found to be maximum in the summer season. Hence, it is found to be the best suited green alternative for combating the fluctuating pollutant load.