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To reduce the cost of adsorbents for the removal of cat urine odor there has been concerted research efforts to produce functionalized porous carbon from waste biomass. In this work, a cost-effective and environmentally friendly method was used to prepare a carbon adsorbent (AC-SNP) from sugarcane bagasse through ultrasonic-assisted impregnation of mixed HNO3/H3PO4 on bagasse prior to carbonization. Ultrasonication enhanced structural deformation of bagasse and enriched the N and O-containing groups prior to cabonization which allowed the final carbon material to have increased specific surface area of 1603.1 m2/g and porosity of 1.3858 cm3·g−1 (including micro- and meso-pores), and increased surface functionality of -COOH, -OH, pyrrolic N, and pyridinic N groups. The adsorption capacity of the carbon material for 3-mercapto-3-methyl-1-butanol (MMB), a volatile cat urine component, was up to 207.12 mg/g at 25 °C, and the heterogenous multi-layer Freundlich model and Pseudo-second-order model were used to explain the adsorption mechanism. Density functional theory (DFT) calculations showed that there are electrostatic interactions and hydrogen bonding between the O- and N-containing groups and MMB molecules. AC-SNP was found to be nontoxic in a cat litter formulation, and removes 99.87% volatile MMB at a low loading ratio of 2 wt%. The fabricated sugarcane bagasse-based cat litter (SB_CL) formulation also has anti-bacterial properties, and so has significant commercialization prospects.

The clarification of sugarcane juice is a crucial stage in the sugar manufacturing process, as it affects evaporator performance, sugar quality and yield. The emergence of environmentally friendly and efficient adsorption technology has resulted in widespread interest in carbon-based materials. However, their low adsorption capacity and reusability make them unsuitable for processing sugarcane juice. Here, we provide a cost-effective and sustainable method to dope hydroxyapatite (HAP) nanoparticles on porous carbon (BBC) derived from sugarcane bagasse (BBC-HAP). The composite shows excellent adsorption capacity for color extract from sugarcane juice of 313.33 mg/g, far more effective than the commercially available carbon-based adsorbents. Isotherm studies show that the adsorption of BBC-HAP composite to the colorants is a monolayer process. The pseudo-first-order (PFO) and pseudo-second-order (PSO) kinetic models demonstrate that the adsorption process is dominated by chemisorption and supplemented by physical adsorption.

China is the third largest sugar producer in the world. However, the sugar industry is challenged by high production costs (attributed to the high cane supply price), which lead to continuous financial deficits for sugar companies. Currently, sugarcane products are primarily composed of white sugar and non-centrifugal sugar (NCS); the utilization of sugarcane by-products (i.e. bagasse, filter mud, and molasses) has also been partially industrialized. However, these strategies are far from adequate to address the challenge. China has successfully developed an innovative sugar manufacturing process using nano-ceramic membrane technology to overcome this predicament. In addition, concepts of high-value diversification of sugarcane products and value-added utilization of industrial byproducts have been proposed. A series of sugarcane-based products, e.g. NCS produced by nano-ceramic membrane technology (MNCS), sugarcane-based beverages, plant water, and cultivation substrates, have been developed to improve the overall return of sugar enterprises. Thus, this paper mainly summarizes the diversification of sugarcane products and their development opportunities in China.

Concentrated sugarcane juice (CSJ) is considered as one of the healthy sugar products, and so a potential feedstock in beverage formulations and soft drinks. However, irreversible aggregates, which are unattractive to the customer, are found with CSJ derived from the membrane filtration during storage. This study examined the formation of aggregates during the concentration of sugarcane juice to CSJ, and during CSJ storage. The concentration process for the formation of the aggregates goes by 3 stages, with polysaccharides interacting with phenolics and then proteins to form complexes which bind non-covalently to SiO2. For stored CSJ, inorganic compounds (mainly SiO2) were the main constituents in aggregates accounting for 43.14 % (w/w), followed by proteins, phenolics, polysaccharides, organic acids, and lipids. The results obtained with stored CSJ/NCS indicate that the proteins interact with phenolics and polysaccharides to form the flocs which then co-precipitate with SiO2 and calcium salts. The polishing of sugarcane juice with a multifunctional adsorbent in combination with the membrane filtration process could be a prospective approach solve the haze/aggregation problems associated with the CSJ, and further promotes their application in beverage formulations.

The development of volatile compounds and their precursors during the dehydration process of membrane-clarified sugarcane juice to non-centrifugal sugar (NCS) was investigated. Head-space solid phase microextraction/gas chromatography–mass spectrometry (HS-SPME/GC–MS) coupled with chemometrics was employed to assess the differences at the various stages of the dehydration process. A total of 111 volatile compounds were identified, among which 57 were endogenous compounds from sugarcane juice and displayed an attenuated abundance in the first 30 min. Typical oxygen and nitrogen heterocyclic compounds, including furans and pyrazines, and aldehydes derived were found to be the main volatiles contributing to the formation of NCS characteristic aroma, with phenols, alcohols, esters, acids, and sulfur compounds as supplementary odor. Free amino acids and reducing sugars were identified as important precursors for the aroma development process. The low temperature (90–108 °C) and micro vacuum condition (−0.03 MPa) approach used in this study could be an alternative option for the manufacture of NCS.