Heavy metals are the major concern of the modern age. Among the heavy metals, chromium (Cr(VI)) is regarded as a highly toxic heavy metal released largely from leather tanning operations. To remove such high concentrations of Cr(VI), an advanced method is required urgently. Thus, biosorption using biochar, which is an organic material produced from various sources such as walnut shell, can be applied successfully for Cr(VI) abatement. The major objectives of this experiment were the remediation of the Cr(VI) heavy metal using walnut shell biochar and checking of the effect of pH, biochar dosage, Cr level, and shaking time. Remediation of Cr(VI) using walnut shell biochar was proved to be effective and removed the maximum concentration of Cr(VI) up to 93% at pH 5.5, 2 h agitation time, and the biochar amount of 1.1 g L−1 from an aqueous solution. Equilibrium modeling demonstrated that the chemisorption process was involved in adsorption of Cr(VI). The surface of the biochar was porous and provided numerous sites for Cr(VI) attachment, which was also confirmed by the presence of Cr(VI) onto the biochar after adsorption. Hence, the use of walnut shell biochar was highly effective as a sorbent, which could conveniently be applied to small-scale as well as large-scale levels.

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Pakistan’s power sector has undergone extensive reforms to improve its technical and monetary performance over the last two decades. However, despite its fast-growing and hazardous nature, safety research remains limited in this context. This study aims to address this gap by assessing the level of safety climate in the power sector and comparing the safety climate in plants operated by multinational companies (MNCs) and local companies (LCs).To this end, five power plants operating in the southern part of the Punjab region (in Pakistan) were included in this study. The Nordic Occupational Safety Climate Questionnaire (NOSACQ-50), an analytical tool comprising of 50 items across seven dimensions, was used to determine the level of safety climate. An independent T-Test was then applied to compare the means in two different setups to draw a conclusion about overall safety climate differences. In MNCs, overall management/leadership perception improved; however, workers in both setups responded similarly in many cases. The lowest observed score in both setups was related to worker’s prioritization of safety and risk non-acceptance. The study highlights the importance of a company’s policies, procedures, and leadership commitments in creating a stronger safety climate by instilling trust in workers. The study further demonstrates that cross-cultural and strong policies devised by multinational companies help to improve the overall safety climate andconcludes that promoting an efficient and positive safety climate in the power sector is a long journey and that can only be achieved if all workers and leaders take on an active role.

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