This study examined the removal of Pb2+ions from aqueous solution with two different lead concentrations using a hydrogel-forming polymer based on hydroxypropyl cellulose (HPC) and sodium alginate (SA). The feasibility of the adsorption behavior of SA/HPC beads has been investigated with three varying ratios of 50:50, 75:25 and 100:0 under a stir condition. The adsorption experiments were done to determine the effects of contact time, lead concentration and SA-HPC ratio to the adsorption capacity of SA-HPC hydrogel beads. The results showed that the ratio 75:25 showed higher adsorption capacity compared to 100:0 and 50:50. It showcased 47.72 mg/g adsorption capacity and 95.45% adsorption percentage after three hours of contact time. The adsorption kinetic model indicated that the adsorption of Pb2+ions onto the beads followed a pseudo-second order kinetic equation. This means that the adsorption mechanism shows a chemisorption process and its sole rate-limiting step is intraparticle diffusion.
Considering how much protein is loaded into the process, the crosslinking solution concentration and the weight percentage of the alginate/hydroxyethyl cellulose coating material, this study presented the details of optimization of the microencapsulation process. Optimization was done with an objective of maximizing the encapsulation efficiency of the microparticle fabricated using external ionotropic gelation method. Results showed that the process is capable of achieving around 75% encapsulation efficiency when protein loading is around 15 wt%, alginate/hydroxyethyl cellulos is about 2 wt% and the CaCl2 solution should be 3 wt%. This was done using Box-Behnken methodology wherein the predicted model was found to have good predictive capability. Analysis also showed that the process is affected by how much protein drug is loaded into the system and the interactions between crosslinking solution concentration with bovine serum albumin (BSA) loading as well as the strong relationship between alginate/hydroxyethyl cellulos concentration with itself.
In the Philippine agricultural setup, pre-harvest cacao (Theobroma cacao) fruits are wrapped with low-density polyethylene (LDPE) for moisture retention and damage protection. Responding to the growing concern for its waste volume and scarcity of treatment, this research explores the co-hydrothermal carbonization (co-HTC) of cacao shells (CS) and LDPE as a method to convert agricultural waste with plastic into hydrochar of potential energy applications. Thus, observations on the thermal, physicochemical, and morphological changes from feedstocks to hydrochar are carried out. Optimal conditions of 200 °C for 60 minutes resulted in hydrochar with 21.11 MJ/kg and appreciable thermal properties. SEM micrographs show rough and porous structures of hydrochar powder and presence of cracks on oversized LDPE film, while EDX analysis reveals C, K, Ca, and Zn metals that affects chemical pathway. FTIR analysis further supports chemical synergy by preservation of functional groups innate from both parent materials, as well as relative LDPE degradation due to chain scissoring and oxidative reactions. Kinetic and thermal evolutions are also investigated to reveal influence of pretreatment to the stability of cacao shells-dominated hydrochar and the effectivity of biomass integration to facilitate relatively easier degradation of LDPE. The findings support co-HTC as a viable technology to enhance the circular economy by valorizing LDPE and cacao shells while promoting energy recovery.
In the Philippines’ agricultural setup, pre-harvest cacao (Theobroma cacao) fruits are wrapped with low-density polyethylene (LDPE) for moisture retention and damage protection. Responding to the growing concern for its waste volume and scarcity of treatment, this research explores the co-hydrothermal carbonization (co-HTC) of cacao shells (CS) and LDPE as a method to convert agricultural waste with plastic into hydrochar for potential energy applications. Thus, observations on the thermal, physicochemical, and morphological changes from feedstocks to hydrochar are carried out. Optimal conditions of 200 °C for 60 min resulted in hydrochar with 21.11 MJ/kg and appreciable thermal properties. SEM micrographs show that hydrochar had increased surface area, a good fuel characteristic, and surface flaking on oversized LDPE film, suggesting relative LDPE degradation. EDX analysis reveals C, K, Ca, and Zn metals that affect chemical pathways. FTIR analysis further supports chemical synergy by preservation of functional groups innate from both parent materials. Kinetic and thermal evolutions are also investigated to reveal the influence of pretreatment on the stability of cacao shell-dominated hydrochar and the effectivity of biomass integration to facilitate relatively easier cracking of LDPE. The findings support co-HTC as a viable technology to enhance the circular economy by valorizing LDPE and cacao shells while promoting energy recovery and solid fuel production.
In this study, nanocrystalline cellulose (NCC) was synthesized using mixed H 2 SO 4 /formic acid hydrolysis from waste cassava pulp produced in Northern Mindanao, Philippines. The study investigated the extraction yield with respect to acid concentration, hydrolysis temperature, and time; the optimal set of such factors; and the characteristics of the optimized NCC. The raw material was pretreated with 4 wt% NaOH and bleached with 4% (w/v) NaOCl. Hydrolysis conditions were formic acid concentration of 50–88 wt%, temperature of 70–90°C, and time of 1–6 hours. Five (5) wt% H 2 SO 4 was also added as a catalyst. Based on the results, increased factor values contributed to higher extraction yields, but too much resulted in a decrease. Optimization resulted in the set of factors (71 wt% formic acid, 77°C, and 3.6 hours) with a yield of 67.272% ± 2.295%. FTIR analysis indicated effective removal of lignin and hemicellulose during the pretreatment. Furthermore, SEM images and DLS indicate nano-size dimensions with hydrodynamic diameters from 15 nm to 687 nm and a zeta potential of -14.3 mV. The NCC produced in this study has been found to have comparable extraction yield as previously reported with smaller reported hydrodynamic diameters and less tendency for self-aggregation.