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This work encompasses using acid-base modified rubber seed shell biochar (RSSB) as an adsorption approach to eradicate phenol from aqueous mediums. Potassium hydroxide (KOH) was used pre-pyrolysis to modify the RSS, and hydrochloric acid (HCl) was used post-pyrolysis to modify the RSSB. The methodology was divided into three stages: RSS pretreatment, RSS base-modification and pyrolysis, and RSSB acid-modification and processing. Temperature, pH and several other factors were investigated for their impacts on the adsorbent, and optimal conditions were established at pH 6, 1.0 g of rubber seed shell biochar (RSSB), 50 mg/L initial concentration, 120 min contact time, and 30 °C temperature. The highest phenol removal efficiency was recorded at 97.21 % using the RSSB-700 adsorbent. Thermodynamic, kinetic and isotherm studies were carried out on the adsorbents using the non-linear modelling approach. The pseudo-second-order kinetic model was declared optimal because the adsorption rate closely followed it, with minimal difference between the experimental and computed values. The maximum RSSB adsorption capacity is 13.32 mg/g, according to the equilibrium results, which follow the Langmuir isotherm equation. Thus, the aim of this research and all documented objectives have been fulfilled.

Pollution generated by solid waste has become a massive source of concern worldwide as the amount of waste being generated has become overwhelming. Waste paper contributes significantly to the overall solid municipal waste being generated daily and with control methods that are equally bad for the environment or just plain ineffective; better, effective, and environmentally friendly control solutions are required. This study reviews the use of various microorganisms as they aid in the control of waste papers in an environmentally conscious way. In addition to being an environmentally friendly solution to the issue of solid waste paper pollution, it is also a prominent source of renewable energy in the conversion of paper into fermentable sugars for the production of bio-ethanol. This review examines the vital revolution in the enzymatic hydrolysis of paper to sugar. Salient challenges that involve bioconversion were highlighted and a few solutions were suggested.

The effect of some physical and chemical treatments on the functional and pasting characteristics of native tigernut starch (TNNS), native sweet potato starch (SPNS) and blends of tigernut-sweet potato starch were studied. Native tigernut and sweet potato starches were subjected to physical (annealing and heat-moisture) and chemical (acetylation) modifications and compared to tigernut (T)-sweet potato (S) starches blends (T75:S25, T50:S50, T25:S75). Only heat-moisture treatment (THMT) significantly (p ≤ 0.05) increased water absorption capacity of the TNNS while only acetylation significantly (p ≤ 0.05) increased the oil absorption capacity of the native tigernut starch. The bulk density was significantly (p ≤ 0.05) reduced by annealing and acetylation. In addition, TNAS, mixture of blends and SPNS had higher swelling capacity than TNNS. The final and peak viscosities of TNNS, SPNS and all the starch blends were between (217–280 RVU) and (214–395.3 RVU) respectively with SPNS having the highest values, followed by T75:S25 (75% tigernut starch: 25% sweet potato starch) and TNNS in that order. TNNS also had the highest setback viscosity. Samples THMT, TANN and TNAS significantly (p ≤ 0.05) reduced the breakdown viscosity and the pasting temperature. The scanning electron micrograph showed that the native and modified starches of tigernut were similar to those of other starches. Overall, the results showed that many of the pasting characteristics of TNNS were comparable to SPNS, while SPNS had with better functional characteristics.